ORHVS

Module 1 to 4

Questions & Answers.

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HV module 1 to 4 questions and answers.

Module 1

Lesson 1 Background of ORHVS

Question 1Explain the consequences of a contravention of the ORHVS?

Answer 1If you contravene the ORHVS you will also contravene the OHS Act andbe liable to a fine or jail sentence or both.

Question 2Explain the difference between the ORHVS and Area Operating Regulations.

Answer 2ORHVS apply throughout Eskom. Whereas area operating regulationsare usually restricted to one station or area only and must not contradictthe ORHVS.

Question 3Explain how the employer will comply with the act in terms of the duty to inform?

Answer 3As far as is reasonably practicable, cause every employee to be madeconversant with the hazards to his health and safety attached to anywork which he has to perform, any article or substance which he has toproduce, process, use, handle, store or transport and any plant ormachinery which he is required or permitted to use, as well as with theprecautionary measures which should be taken and observed withrespect to those hazards.

Question 4List four dangers of HV electricity and the precautions to be taken.

Answer 4

Dangers Precautions

Electricity is invisible

Electricity follows the path of leastresistance (Human body is aconductor of electricity)

Electricity can jump gapsCausing current flow through thehuman body

Regard conductors as aliveuntil proven dead. TESTBEFORE TOUCH

Avoid contact

Don’t approach too close tolive high voltage conductorsSpecifically with conductivematerials

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A terrific uncontrollable arc of ±25000°C is generated whenevercurrent flow is interrupted

Operating to be done in thecorrect sequence

Question 5The operating regulations are based on the fundamental principle that no person

shall carry out work of any description on any part of high-voltage apparatus unless those parts are:

Answer 5Those parts are:- Dead.- Effectively isolated (Air gap) and all practical steps have been taken to lock such apparatus off from all live conductors.- Effectively and adequately connected to earth at all points of disconnection of supply to such apparatus and on both sides of the workplace.- Effectively barricaded (screened off) to prevent inadvertent contact and warning notices/signs put up.- Released for work by the issue of a work permit.- The workers register/Risk assessment/Pre Job check list and relevant documentation is to be completed.

Question 6Describe the term "high-voltage".

Answer 6A nominal AC or DC voltage greater than 1000 volts.

Question 7Explain what does the Occupational Health and Safety Act state about anything

which is provided in the interest of health and safety.

Answer 7No person shall intentionally or recklessly interfere with, damage or misuse anything, which is provided in the interest of health and safety. E.g.: unauthorised overriding of protections or safety devices.

Question 8Is it only possible to receive an electrical shock by actual contact?

Explain your answer.

Answer 8No, electrical voltage can jump air gaps if the human body is close enough.

Question 9Describe the purpose of the regulations?

Answer 9* Ensuring the health and safety of all persons.

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* Safeguard electrical apparatus from damage.* Safeguard the continuity of supply.

Question 10Explain why do we need Eskom Regulations when we have the OHS Act?

Answer 10The Government regulations cannot cover every possible condition in every industry and therefore only lay down broad policies. The ORHVS lay down in more detail how the requirements of Government Policy Regulations are to be met within Eskom.

Question 11Explain your responsibilities as an authorised person regarding knowledge of the

ORHVS?

Answer 11Becoming thoroughly conversant with the contents of the regulations applicable to his/her authorisation.Knowing the regulations.Compliance with the regulations.

Question 12May a person be authorised as an appointed operator and a responsible person, and

simultaneously exercise both authorisations on the same work permit?

Answer 12Yes. One person could perform the functions of both appointed operator and the responsible person, but he cannot exercise both authorisations on the same work permit.

Question 13State your responsibilities as an authorised person concerning amendments to the

regulation book?

Answer 13Any amendments to the H.V. Regulations will be issued to all persons having copies thereof and they must update their books and acquaint themselves with the changes.

Question 14List 2 fundamental principles for control and access on which the Regulations are

based.

Answer 14The regulations are based on the following principles:Control must be exercised over power system conditions and operating procedures at all timesAccess to high-voltage conductors and apparatus must be strictly controlled.

Question 15List 3 general duties of Employers to their Employees.

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Answer 151) Every employer shall provide and maintain, as far as is reasonably practicable, a working environment that is safe and without risk to the health of his employees.2) Without derogating from the generality of an employer’s duties under subsection (1), the matters to which those duties refer include in particular:

a) The provision and maintenance of systems of work, plant and machinery that, as far as is reasonably practicable, are safe and without risks to health.

b) Taking such steps as may be reasonably practicable to eliminate or mitigate any hazard or potential hazard to the safety or health of employees, before resorting to personal protective equipment.

c) Making arrangements for ensuring, as far as is reasonably practicable, the safety and absence of risks to health in connection with the production, processing, use, handling, storage or transport of articles or substances.

d) Establishing, as far as it is reasonable practicable, what hazards to the health or safety of persons are attached to any work which is performed, any article or substance which is produced, processed, used, handled, stored or transported andany plant or machinery which is used in his business and he shall, as far as is reasonably practicable, further establish what precautionary measures should be taken with respect to such work, article, substance, plant or machinery in order to protect the health and safety of persons, and he shall provide the necessary means to apply such precautionary measures.

e) Providing such information, instructions, training and supervision as may be necessary to ensure, as far as is reasonably practicable, the health and safety at work of his employees.

f) As far as is reasonable practicable, not permitting any employee to do work or to produce, process, use, handle, store or transport any article or substance or to operate any plant or machinery, unless the precautionary measures contemplated inparagraphs (b) and (d), or any other precautionary measures which may be prescribed, have been taken.

g) Taking all necessary measures to ensure that the requirements of this Act are complied with by every person in his employment or on premises under his control where plant or machinery is used.

h) Enforcing such measures as may be necessary in the interest of health and safety.

i) Ensuring that work is performed and that plant or machinery is used under the general supervision of a person trained to understand the hazards associated with it and who has the authority to ensure that precautionary measures taken by theemployer are implemented.

j) Causing all employees to be informed regarding the scope of their authority, as contemplated in section 37(1) (b).

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Question 16List 3 general duties of Employees at work.

Answer 16Every employee shall:Take reasonable care for the health and safety of himself and of other persons who may be affected by his acts or omissions.As regards any duty or requirement imposed on his employer or any other person by this Act, co-operate with such employer or person to enable that duty or requirement to be performed or complied with.Carry out any lawful order given to him, and obey the health and safety rules and procedures laid down by his employer, in the interest of health and safety.If any situation which is unsafe or unhealthy comes to his attention, as soon as practicable, report such situation to his employer or to the health and safety representative for his workplace or section thereof, as the case may be, who shall report it to the employer.If he is involved in any incident which may affect his health or which has caused an injury to himself, report such incident to his employer or to anyone authorised thereto by the employer, or to his health and safety representative, as soon as practicable but not later than the end of the particular shift during which the incident occurred, unless the circumstances were such that the reporting of the incident was not possible, in which case he shall report the incident as soon as practicable thereafter.

Lesson 2 Reasons for isolating

Question 1Explain how one circuit can be electrically connected to another. (Give an example

of each i.e a, b & c)

Answer 1(a) A solid conductor, such as copper, aluminium or the human body.(b) An invisible magnetic field: (inductance) such as in a transformer(c) An invisible electrostatic field: (capacitance) such as in capacitor.

Question 2Explain why you cannot normally regard the opening only of a circuit breaker as an

isolation?

Answer 2It is unsafe because:* There is no air gap.* The breaker can be closed accidentally.* Apparatus can retain a static or magnetic charge.

Question 3Describe the term "dead".

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Answer 3At or about zero potential and disconnected or isolated from any live power systems. Rotating plant shall not be regarded as dead until it is stationary or being slowly rotated by means of a barring gear and is not excited.

Question 4Explain how would you know if a conductor is dead and safe to work on?

Answer 4Only when you can see an earth on the conductors or apparatus on both sides of the workplace.

Question 5List five ways in which isolation from electrical potential can be done:

Answer 5* Opening and/or removal of fuses.* Opening of isolators.* Removal of jumpers/droppers.* Opening of air break switches.* Racking out of truck-type switchgear.* Immobilisation of breakers having visible contact separation, and not fitted with grading capacitors.

Question 6According to the regulations why are air break switches, truck-type switchgear or

fuses regarded as isolators?

Answer 6* They leave an air gap in a circuit when open, removed or withdrawn.* They contain no stored energy and will not close due to defects.* They can be locked in a physical position and can thus only be operated by the person with the correct key.

Question 7List the exception to the general rule with regards to the isolation of breakers.

Answer 7In the case of certain generator breakers, there are no isolators. As long as the circuit breaker can be immobilised so that it cannot be closed and an air gap created, it will provide a safe

Question 8Describe the term apparatus.

Answer 8Apparatus means any generator, transformer, motor, switchgear, isolator, feeder, electrostatic precipitator or any other high voltage plant installed in a station.

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Question 9Describe the term power system.

Answer 9Power system means the power stations, feeders, substations and apparatus whereby electrical energy is made available to the consumers’ points of supply.

Lesson 3 Reasons for earthing

Question 1Explain the importance to earth apparatus before work can be done safely?

Answer 1Because the apparatus can:Retain a charge.Acquire a static charge due to atmospheric conditions.Accidentally be made alive.Nearby lines continuously induce voltages in it.

Question 2Describe the term "earthing".

Answer 2Earthing means the connecting of apparatus electrically to the general mass of earth in such a manner that will ensure an immediate safe discharge of electrical energy at all times.

Question 3Explain why is it important to earth a line?

Answer 3To discharge them should there be a residual voltage or charge.To prevent them acquiring a static charge.To ensure a safe discharge of electrical energy when lines or apparatus are being accidentally made alive whilst persons are working on them.To dissipate induced voltages continuously.

Question 4Explain how rotating plant can generate a dangerous High Voltage?

Answer 4When rotating at speeds higher than barring speed.

Lesson 4 Control of access

Question 1Explain the difference between a live chamber and a prohibited area.

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Answer 1In a live chamber it is possible to touch live conductors from ground or floor level, whereas in a prohibited area this is not possible.

Question 2Explain what is meant by ground or floor level.

Answer 2Ground or floor level means a permanent structure that is designated to walk on and can be elevated.

Question 3Explain who may gain "unrestricted access" to prohibited areas?

Answer 3Only authorised persons authorised thereto may gain unrestricted access to prohibited areas.

Question 4Describe the term "barrier" and give one method of barricading part of a prohibited

area.

Answer 4A barrier means any device designed to restrict approach to live high voltage electrical apparatus. Shark nets around the work area with warning notices or signs attached to it.

Question 5Explain in detail the conditions under which persons other than authorised persons may gain access to and to work in a prohibited area:(i) Ground or floor level only(ii) Above ground level

Answer 5i. When under supervision of an authorised person (RP). When working under a work permit under continuous supervision.

ii. The working area is suitably demarcated by means of barriers to ensure that inadvertent human contact with live apparatus is not possible from within the barriers. A work permit shall be issued detailing the apparatus on whichwork is required. When under supervision of an authorised person (RP).

Question 6Describe how can you remain safe in a prohibited area?

Answer 6Stay on ground level.Stay within the barriers.

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Question 7Describe your understanding of the following

(i) Supervision(ii) Authority(iii) Why is the above necessary?

Answer 7i. To direct or watch the actions, work or proceedings with authority.ii. The power to enforce obedience.iii. To ensure that work or proceedings are carried out safely.

Question 8Explain when will an area within a prohibited area no longer be considered

prohibited?

Answer 8If a section of a prohibited area, and its access, is effectively separated or segregated from the remainder of the prohibited area so as to prevent dangerous approach to live apparatus, it shall no longer constitute a prohibited area.

Question 9Explain the duty of the supervisor when workers leave the restricted or prohibited

area where they have been working, i.e. at the end of the day?

Answer 9Accompany them until they have left the area, lock the doors/gates and sign the workers register.

Question 10Describe the procedure for access of persons to restricted areas?

Answer 10Shall only be allowed to persons who have obtained permission through authorised methods e.g.: Work permit, Under supervision of an authorised person. If you are an authorised person.

Question 11According to the regulations when the authorised person responsible for supervision

is no longer available what must be done?

Answer 11He shall in all cases, before departing, delegate on the workers register another authorised person (RP) to take responsibility for supervision or withdraw all the workers if another Authorised person is not available.

Question 12Describe what does a Warning Notice or sign indicate?

Answer 12Calling attention to the danger of approach to, or interference with the apparatus to which it is attached and to indicate any special operating condition.

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Question 13State the requirements must be met before a person can be authorised?

Answer 13The person must be suitably selected, trained, examined and found competent by the examining committee.

Question 14Who may perform emergency switching?

Answer 14Any person may perform emergency switching.

Question 15Describe in your own words the term "emergency switching".

Answer 15Emergency switching is the opening only of such breakers or switches as may be necessary in order to avoid imminent danger to life or damage to apparatus.

Question 16Explain what must be done after emergency switching has taken place?

Answer 16The control officer must be informed as soon as possible of the details and the names of the person who has done the emergency switching.

Question 17Give two reasons why you are not allowed to re-close circuit breakers after

emergency switching?

Answer 17Because, during emergency switching, sections of the system may have fallen out of parallel or the control officer may have received information, which prohibits re-energising of the apparatus.

Lesson 5Issue and use of keys

Question 1The keys of a prohibited area shall have a label attached to them. State the

information that must be marked on the label?

Answer 1The name of the Prohibited area.Distinguishing number corresponding to the number on the lock to which the door gives access.

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Question 2State where prohibited area keys are to be kept, and who is responsible for the

safekeeping thereof?

Answer 2Prohibited area keys must be kept under lock and key in the cabinet provided for that purpose. The key for this cabinet must be kept in the custody of the person on duty responsible for the issue and return of these keys.

Question 3List five responsibilities of persons authorised to use keys.

Answer 3Lock or guard the gate/door after entry (Reg. 3.01.1).Ensure that unauthorised persons do not enter except in terms of Reg. 3.02, 3.03 and 3.04 which must be enforced.Withdraw all persons on leaving.Lock gate and/or doors on leaving.Keys must never be left in locks.

Question 4Describe how must each door or gate giving access to a prohibited area be marked?

Answer 4The door or gate shall be marked with the name of the prohibited area. Where necessary with a distinguishing number close to the lock.

Question 5Explain who may use master keys and which master keys may be used by them?

Answer 5Only authorised persons authorised thereto shall use master keys for access to prohibited areas at power stations.

Question 6State when issuing prohibited area keys, what details must be recorded in the key

book?

Answer 6(i) The particulars of the key(ii) To whom the key is being issued.(iii) The time and date of issue.(iv) The signatures of the person receiving and the person issuing the keys.(v) The receipt on return of the key shall also be logged in the key book.

Question 7According to the regulations why doors and gates of live chambers / prohibited and

restricted areas must be closed and locked?

Answer 7

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To prevent unauthorised entrance to these dangerous areas.

Question 8a) Explain when may doors and gates to restricted areas and prohibited areas

remain unlocked?b) Explain the reason for this and which condition must be met.

Answer 8a) While work and/or operating is in progress in a prohibited or restricted areab) To facilitate an emergency exit. Provided no unauthorised person may gain unrestricted entrance.

Question 9Explain what must be done when Prohibited/Restricted area keys are lost?

Answer 9Loss of keys shall be immediately reported to the relevant head of the department.

Question 10During what conditions will substation doors be closed and locked?

Answer 10Substations shall be kept closed and locked when unattended.

Question 11State the responsibilities of persons entering prohibited and restricted areas?

Answer 11* They must lock the doors or gates after entering (Reg. 4.01.4).* They must control access if an entrance is kept open (Reg. 3.01.1).* Ensure that unauthorised persons do not enter except in terms of Reg. 3.03 and 3.04 which must be enforced.

Question 12Explain what must be done when leaving a restricted or prohibited area?

Answer 12The person to whom the key has been issued will see that all persons have withdrawn from the restricted or prohibited area and that the doors or gates are securely closed and locked.

Module 2

Lesson 1 Officials and Employees

Question 1Describe the term control officer.

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Answer 1An employee on duty at a control centre, who is responsible for the general operation of the power system or section thereof.

Question 2Explain why we have a " Control Officer ".

Answer 2To have a form of centralised control in order to prevent the whole system from collapsing in chaos.

Question 3According to the regulations what does authorised or authorise refer?

Answer 3Refers to the giving of permission in writing to perform specific duties in terms of these regulations. Authorisation remains valid for a maximum period of Two years.

Question 4Describe the term responsible person.

Answer 4Responsible person means a person, who has been authorised to be responsible for ensuring that the work on the apparatus covered by a work permit can be carried out safely and within the terms of these regulations.

Question 5According to the regulation what does supervise or supervision refer to?

Answer 5Supervision or Supervise refers to the overseeing of the actions of a person or persons so as to prevent any act that could be dangerous or in contravention of these regulations.

Question 6Describe the term appointed operator.

Answer 6Appointed operator in Power Stations means a person, who is authorised to do operating and is deemed to be an authorised person, in terms of these regulations.

Question 7Describe the term "High-voltage authorisation form".

Answer 7High voltage authorisation form means the printed form used for detailing, the extent of authorisation in terms of these regulations.

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Question 8Reg. 5.01 states that only authorised persons shall carry out switching, linking,

safety testing and earthing. This regulation mentions two exceptions describe them.

Answer 8Where persons are being trained for operating authority, they may operate under supervision of an appointed operator, with the knowledge of the control officer.The switching of power station auxiliary motor circuits by remote control is excluded from this regulation.

Question 9According to the regulation before a person shall be authorised, what must the

training consist of?

Answer 9Both theoretical and practical training of high voltage operating.

Question 10According to the regulation Reg. 5.06 - supervision what will the responsible person

be held responsible for?

Answer 10For the safe execution of all work and activities as far as compliance with these Regulations is concerned, whether this is carried out by employees, or by non-employees contractors and by persons employed by the contractors.

Question 11Name three authorised persons in accordance with these regulations

Answer 11Control officer.Responsible person.Appointed operator.

Lesson 2Purpose of the Work Permit System

Question 1State the purpose of the work permit system?

Answer 1The purpose of the work permit system is to ensure the safety and health of personnel while work is being performed.

Question 2Explain when is a work permit required?

Answer 2A work permit is required for all work on apparatus by employees of any department of Eskom or by contractors.

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Question 3Explain what does a work permit authorise?

Answer 3A work permit authorises access to restricted or prohibited areas, for work to be done on apparatus according to these regulations.

Question 4Explain to whom may appointed operators issue permits?

Answer 4Only to responsible persons.

Question 5Explain when may a contractor take out a permit on Eskom apparatus?

Answer 5If he is a responsible person in terms of these regulations.

Question 6Explain where will a customer's representative endorse a permit?

Answer 6In the space where the responsible person would sign.

Lesson 3 The Work Permit System

Question 1a) Describe the application section of the work permit.

b) Describe the permit section of the work permit.c) Describe the clearance section of the work permit.

Answer 1a) The application section identifies the apparatus to be worked on, the nature of the work to be carried out, the isolations to be carried out, the number and position of earthing devices, the time and date and signatures of the authorised persons concerned, any special requirements including identified dangers and hazards and the risk assessment number must be entered on to the work permit prior to printing”..b) This is the second section of the work permit form signed by the appointed operator and responsible person, indicating the key safe and safety lock numbers, with the time and date of issue.

c) The clearance section is the last section of the work permit form signed by the responsible person and the appointed person with time and date declaring that the apparatus can be returned to service safely.

Question 2Explain what must the appointed operator do on receipt of a work permit application?

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Answer 2The appointed operator on duty shall verify that dangers and hazards have been identified on the application section of the work permit, before he signs the application. Where applicable, the appointed operator will make arrangements with the control officer to have the apparatus isolated and earthed.

Question 3State what must the appointed operator and responsible person do before the

responsible person signs the work permit?

Answer 3They must satisfy themselves that the apparatus is isolated and safe to work on as stated on the work permit application.

Question 4Explain why must the responsible person take possession of the original copy of the

work permit form?

Answer 4It is his only guarantee that all the isolations stay as it was done and no changes can be done on the work permit.

Question 5Explain what must be done with the work permit book when full and all work permits

have been cleared?

Answer 5When the work permit book is full and all work permits have been cleared, it must be returned to the office of the official in charge and a new book is taken into use. The completed book may be destroyed at the instructions of the official in charge after a lapse of one year provided that no query has arisen regarding any entry contained init.”

Question 6According to the regulation does the workers sign the workers register or declare

anything?

Answer 6No. The responsible person shall explain the nature of the work covered by the work permit and the dangers/ hazards and precautions as per the pre-work checklist, attached thereto to all the workers who will be engaged in this work and shall then complete the workers’ register

Question 7Explain what is meant by the duration of a work permit.

Answer 7A work permit remains in force until it is cancelled by the issue of a clearance.

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Question 8State the time limit for advance work permit applications?

Answer 8There is no time limit for advanced work permit applications.

Question 9May persons work under more than one work permit at a time? Explain.

Answer 9No, because there is certain information that he must remember during a specific job. If you work on more than one work permit, you may get confused and endanger your life and/or apparatus.

Question 10Explain why must a work permit be issued for each section of plant?

Answer 10The apparatus in a specific circuit is situated on different floor levels and/or rooms and chambers.If the workers work under a work permit for each section, the work is completed and the work permit is signed off for each section, it helps to ensure that all workers have been withdrawn.Each person or group has their work clearly defined.For supervision purposes.

Question 11Explain what happens in cases where the responsible person does not remain at the

work place?

Answer 11The responsible person shall delegate in writing on the workers register another responsible person to supervise during the absence.If another responsible person is not available, all workers shall be withdrawn from the work, during the absence of the authorised person. Doors / gates locked.

Question 12May supervision be delegated, and how will it be done?

Answer 12Yes Change of responsibility on the work permit and delegation of supervision must be done in writing on the workers register and all relevant documents.

Question 13Explain what happens to the duplicate form while the work permit is in force?

Answer 13The duplicate of the work permit stays in the book, where applicable and/or with the appointed operator in the control room.

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Question 14Explain what must the appointed operator do once the responsible person has

signed the work permit?

Answer 14The Appointed operator shall then after signing the work permit, record the time and date on it. The appointed operator must now allow the responsible person to accept the work permit after verification of the risk assessment with the key safe key to the Responsible person together with any keys necessary to give access to the apparatus concerned.

Question 15Explain why must the responsible person state the nature of the work to be carried

out on the work permit application?

Answer 15So that the appointed operator knows exactly what isolations and earths are required for that specific work?

Question 16Describe the term apparatus.

Answer 16Apparatus means any generator, transformer, motor, switchgear, isolator, feeder, electrostatic precipitator or any other high-voltage plant installed in a station.

Question 17Describe the term panel or bay.

Answer 17Panel or bay means all the apparatus in the same circuit situated in Live chambers, prohibited or restricted areas, from and including the bus bar isolators.

Lesson 4 The Key Safe System

Question 1Explain the term "key safe".

Answer 1An approved device for the secure retention of safety lock keys used for locking isolations, earthing or other safety devices necessary for the issue of a work permit.

Question 2Explain the term "operating lock".

Answer 2An approved lock, forming part of a series of locks, operable by common keys in possession of appointed operators only.

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Question 3Explain the term "safety lock".

Answer 3A safety lock is an approved lock for which only one unique key is available. The lock has the same corresponding number as the key.

Question 4State the purpose of the key safe system?

Answer 4To hold the keys of the locks which were used for isolations and earthing or other safety devices in custody for the duration of a work permit.

Question 5Describe the procedure to use the key safe under the following conditions with

reference to related permits:a) Work to be done on apparatus (work permit A)b) Work which requires all or part of the same isolations (work permit B).c) Work which requires not only all or part of the same isolations but also additional isolations (work permit C).

Answer 5a) Work permit "A" keys used for isolation on key safe 1. Locked with operating and safety lock.b) Work permit "B" requires the same isolation as work permit "A". Apply an additional safety lock to key safe 1 and issue the key of the additional lock with work permit "B". Cross-reference both permits.c) Work permit "C" not only requires all or part of the same isolations on work permits "A" and "B", but additional isolations. An additional lock is applied to key safe 1, the key to this lock plus the keys used for the additional isolations are placed on key safe 2. Key safe 2 is then locked with a safety lock and operating lock. The key to this safety lock is then issued with work permit "C". Cross-reference all three work permits.

Question 6State what is meant by key safe integrity?

Answer 6* No person shall at any time open, damage or in any other way interfere with a key safe or the keys retained therein except under the following conditions:* No operating lock may be removed from a key safe whilst any safety lock is still applied on that specific key safe.

Question 7Explain how to extend a full key safe.

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Answer 7Remove operating lock.Replace it with a safety lock.Place the safety lock key on the next key safe.Add the other safety lock keys used for isolation.Lock this key safe with a safety and operating lock.

Question 8.Describe the procedure to gain abnormal access to a locked key safe.

Answer 8* If it should become necessary to gain access to the keys on the key safe for any reason other than for testing under Reg 5.09, permission must be obtained from the relevant Head of the Department who must personally witness the procedure to gainaccess.* The occurrence must be recorded in the appropriate authorised person’s logbook. (Appointed operator)

Lesson 5 Returning Apparatus or Lines to Service

Question 1Describe the procedure to be followed by the responsible person up to and including

a work permit is cleared on completion of work.

Answer 1Clear all tools and debris.Replace all permanent barriers.Tell the workers it is no longer safe to work on that apparatus.Ensure all workers have been withdrawn from the work place. Sign off the appropriate section of the workers register.Lock all doors and gates giving access to apparatus.The responsible person then fills in and signs the clearance section of the work permit on both copies and returns all keys issued to him to the appointed operator.Returns the original copy of the workers register and all relevant documents to the appointed operator.

Question 2State the duties of the appointed operator on receipt of a clearance?

Answer 2Ensure that:The appointed operator immediately signs the clearance.All tools and debris are cleared.All persons have been withdrawn.All permanent barriers replaced.That the original copy of the workers register, risk assessment and pre-work checklist and all relevant documents is attached to the original copy of the work permit and been returned.Notifies the control officer that all work permits have been cleared.

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Question 3Explain when shall earths be removed from the apparatus when work was done in

more than one place in a circuit under separate work permits?

Answer 3Only when all work permits for that specific circuit have been cleared.

Question 4Describe what must be done when the original of the work permit is lost, and the

work permit must be cleared.

Answer 4The appropriate head of department, or in the case of a non-employee, the site representative of that company, must:Confirm that all workers have been withdrawn from the work place.The appropriate section of workers register has been signed and all relevant documentation returned.Countersign the copy of the work permit.

Question 5Explain what must be done when the appointed operator is not satisfied that the

apparatus concerned is ready for service when the work permit is cleared.

Answer 5The responsible person must then be informed.A new work permit must be issued if any further work is required.

Question 6Describe the procedure to be followed should the responsible person to whom the

work permit was issued, not be available to sign the clearance.

Answer 6In the event of the responsible person to whom a work permit has been issued not being available to clear the work permit, the official in charge shall decide which other responsible person shall clear the work permit.

Such responsible person shall first countersign the work permit, and/or complete the “change of responsibility” portion on the computerised work permit form as well as the workers' register, risk assessment and pre-work checklist, to indicate that he is fully aware of what was to be done on the apparatus.

He shall supervise the completion of the work, fill in and sign the clearance on the work permit form and return the work permit form and all relevant documents to the appointed operator concerned.

The official in charge shall take all reasonable steps to ensure that no dangerous condition arises from such transfer of responsibility

Question 7

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Explain the Transfer of responsibility

Answer 7In the event of another responsible person becoming responsible for the work, both the original and the copy of the work permit must be accepted, as well as the workers' register, risk assessment and pre-work checklist, these must be endorsed with the date and time when the new responsible person assumes the responsibilities as the responsible person. The change of responsibility section on the work permit form must be signed by both the outgoing and incomingresponsible person.

Transfer of responsibility may only be used twice on one work permit form, should there be a need for further transfer of responsibility the work permit must be cleared and a new work permit must be issued.

Module 3Lesson 1

ISOLATION FROM SUPPLY

Question 1State who may perform switching, linking, safety testing and earthing?

Answer 1Only appointed operators

Question 2Explain the term "apparatus".

Answer 2"Apparatus means any generator, transformer, motor, switchgear, isolator,feeder, electrostatic precipitator or any other high-voltage plant installedin a station ".

Question 3Explain the term "power station".

Answer 3Power station means a site on which electrical energy is generated and shall also comprise all works necessary or incidental thereto, including buildings and all apparatus up to the point where energy is ready for distribution. It may or may not include any substation situated within the precincts of the power station, as determined.

Question 4Explain the term "auxiliary apparatus".

Answer 4

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The bus bars and apparatus at the station which are supplied by standby generators or the secondary sides of station, unit or earthing transformers or from the tertiary windings of main transformers.

Question 5Explain the term "feeder ".

Answer 5A line or a cable in or from power stations or substations.

Question 6State when must prohibitory signs and earthing labels be applied and removed?

Answer 6* Prohibitory signs must be affixed before any isolation are done and removed last.* Earthing labels must be affixed after the earths have been applied and removed after the earths have been removed.

Question 7Explain the term "generator".

Answer 7Generator circuit means the electrical portion of generating plant; its circuit shall include all the apparatus between its outgoing terminals and the bus bar isolators and between its neutral terminals and earth.

Question 8Explain the terms a) "operating stick", b) voltage testing device.

Answer 8a) The approved insulated rod provided to enable live isolators and fuses to be operated and/or to carry out safety testing and earthing.b) The approved device for the purpose of proving that apparatus is at zero potential

Question 9Explain why must apparatus or feeders be safety tested ?

Answer 9* To ensure that all three phases of the apparatus is disconnected all sources of supply.* To make sure you are at the correct panel.

Question 10State the sequence in which operating is carried out.

Answer 10* Switching, Linking, Safety testing, Earthing.

Question 11

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Explain when and where must prohibitory signs be displayed?

Answer 11Before isolation of a feeder and/or apparatus, a prohibitory sign shall be affixed at each point from where such apparatus can be inadvertently made alive.

Question 12Explain what must the Appointed operator do before applying an earth?

Answer 12By using an approved testing device test the apparatus to be dead before earthing.

Question 13State the reasons why a cable must be spiked before cutting it.

Answer 13Spiking a cable before it is cut ensures that:* If the cable is the wrong one and is still alive, before it is spiked it will not explode in the face of the worker.* If the cable is the right one and is not earthed, spiking will discharge it safely.* A spiked cable indicates that it is safe to be cut.

Question 14State the purpose of prohibitory/warning signs?

Answer 14* Eliminates the need for relying on memory.* It shows the danger points at a glance.* It informs the uninformed.

Question 15State what a “fault condition” is and list two fault conditions?

Answer 15Any condition that will cause excessive current to flow, for example: phase faults, earth faults.

Question 16List the properties or characteristics of a breaker, which enables it to make or break

an electrical current.

Answer 16Designed to:extinguish the arc immediatelywithstand tremendous mechanical forcesIt is fast in operation.

Question 17

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List the properties or characteristics of an isolator, which prevents it from being used as a load current interrupter.

Answer 17it is slow in operationHas no arc extinguishing mediums.

Question 18Describe the likely outcome, if you were to interrupt current flow by means of

isolators in an exposed high voltage overhead line.

Answer 181 It causes an uncontrollable arc which can cause damage to eyes2 High temperature may be generated which will melt the isolators.3 This molten metal can splash onto the operator.

Question 19State when can a breaker normally be regarded as an isolator? ( i, ii, iii. )

Answer 19When:i) Can be locked in an open position.ii) Leaves an air gap.iii) Contains no stored energy.

Question 20Reg. 4.04 demands that isolators shall always be kept locked. Give three reasons for

this.

Answer 20* Earth tremors and vibrations can cause isolators to open or close.* Due to the strong magnetic fields set up during short circuit conditions, it is possible for isolators to fly open.* Provides a safeguard against isolators being opened or closed in error by persons other than the one with the correct key.

Question 21List four effects of a short circuit.

Answer 21* Excessive current will flow.* A large amount of heat will be generated.* A large drop in voltage will take place.* Strong magnetic fields, which exert large mechanical forces, are produced.

Question 22Give three reasons for using an operating stick when applying portable earths.

Answer 22

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* Can stand a safe distance away from contact point.* If alive, it will discharge through the cable and not through the worker.* It is an approved insulated rod.

Question 23Explain what does GGP 1221 state regarding isolated and earthed apparatus?

Answer 23Irrespective of whether the apparatus is isolated (and earthed), immediately prior to commencement of work, the apparatus will be tested for zero potential using a suitable and approved voltage testing device. The “test before touch” (GGD1221) principle must be adhered to.

Lesson 2METHODS OF EARTHING

Question 1State the reasons for earthing?

Answer 1* To discharge residual voltages or charges should there be any.* To prevent them acquiring a static charge.* To prevent lines and apparatus being accidentally made alive while persons are working on it.* To dissipate induced voltages continuously and safely.

Question 2Explain when can work on apparatus be carried out safely?

Answer 2When the apparatus is isolated, tested to be dead and earthed according to the regulations.

Question 3Describe the term "Line".

Answer 3Line means an exposed overhead feeder, and includes the supports and all terminal equipment up to but excluding the line’s transfer/by-pass isolators and line earth switches.

Question 4Explain how you would apply a portable earth.

Answer 4

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After the apparatus has been isolated and tested to be dead: When portable earthing gear is being used, it must first be connected to earthed metal structure, or to a suitable spike driven into the ground. The earthing gear shall then be connected to the apparatus to be earthed by means of an operating stick.Where this is not possible due to space limitations (e.g. indoor substations) hand application of earths shall be covered by area operating regulations.

Question 5Explain what can happen when working on a line which is not earthed, but only

isolated?

Answer 5Workers can be shocked due to static - or induction charges, or accidental livening of the line.

Question 6a) State where must working earths be applied?b) State who authorises them?

Answer 6a) On both sides of the work place and clearly visible.b) The control officer.

Question 7Explain what is a control earth?

Answer 7An earth applied at the instruction of the control officer is a control earth, so that the control officer will always be sure that the minimum earthing requirements are met.

Question 8Explain why working earths must be applied on both sides of the work place?

Answer 8If the line is broken at any point, (for example by the disconnection of a jumper at a strain tower) a dangerous situation could arise.

Question 9Explain where would you earth apparatus other than a line or bus bar?

Answer 9At all points of supply after being isolated and tested to be dead.

Question 10Explain where are bus bars earthed?

Answer 10It shall be earthed at least at one point after being isolated from all sources of supply and tested to be dead.

Question 11

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Explain how transformers are earthed.

Answer 11At all points of supply of the primary, secondary and tertiary windings.

Question 12Explain how metal-clad switchgear is earthed.

Answer 12By means of approved earthing gear provided as part of the switchgear.

Question 13According to the regulations when will earthing switches be opened?

Answer 13The last operation after removing all other earthing gear.

Question 14Name the reason why earth switches must be closed first.

Answer 14* Ensures maximum safety to the operator.* The handle is a safe distance from the contacts.* Make a good connection to an approved earth.* Earth all these phases at the same time.* Interlocked with associated isolating isolators.* The earth switch mechanism can be locked.

Question 15Explain what is a static charge?

Answer 15A static charge is a collection of electrons on the surface of an object, causing a potential difference between the object and earth or some other object.

Question 16List five ways in which an overhead line can acquire a static charge.

Answer 16* Direct lightning strikes.* Lightning strikes in the immediate vicinity.* Presence of thunderclouds.* By the friction of dust or snow blowing past the conductors.* Changes in line altitudes.

Question 17Explain what is residual voltage and name two examples.

Answer 17

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Residual voltage is the voltage remaining in apparatus after it has been isolated and not yet earthed. Example * Capacitor.* Cable.* Motor.

Question 18Name the processes or phenomena responsible for continuously inducing voltage in

overhead lines and the conditions under which this takes place.

Answer 18* Electromagnetic induction or transformer action from a nearby current carrying line.* Electrostatic induction or condenser action from a nearby live line in the immediate vicinity.

Question 19Describe the term "electrically charged".

Answer 19At a potential or voltage above zero.

Question 20State four properties of a safe earth.

Answer 20The clamps should be rigid and without defect.When applied properly, should make intimate contact with the conductors and earth bar or spike.The earthing cable tails should be as short as possible.There should be no broken strands as the current carrying capacity of the earth is greatly reduced by them. It will act as a fuse and increase the danger and risk to workers.Must be made of copper.Must be numbered and on a maintenance schedule.Must have the correct current carrying capacity.Once the earth cable has been exposed to fault conditions it must be discarded and replaced

Question 21Explain when would you consider an overhead line safe to be worked on?

Answer 21When it is effectively earthed, according to the high voltage regulations.

Question 22Under which two conditions would a generator retain a dangerous charge?

Answer 22

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* After megger testing.* Above barring speed.

Question 23State under which two conditions must additional earths be applied?

Answer 23If the earth is not clearly visible from the place of work and when requested by the person in charge of the work.

Question 24Name three earthing devices commonly used.

Answer 24* Earth switches.* Portable earthing cables.* Earthing gear for metal-clad switchgear.

Question 25Name three dangers of inadequate or improper earthing.

Answer 25* Electrocution.* Burns from arcing.* Electric shock leading to falls.

Question 26Describe the term "alive".

Answer 26Alive: Electrically connected to the power system or electrically charged.

Question 27Under what two conditions may work be carried out on a transformer, which has not

been earthed at all points of supply?

Answer 27* When it has been isolated in accordance with these regulations, (tertiary winding feeding a cable must be isolated).* When other windings (primary and secondary) of the transformer have been earthed at their points of supply.

Question 28Describe the behaviour of long earthing cables tails, should the line be made alive

from the power system.

Answer 28* Whipping effect.

Question 29State the requirement when earth switches are closed on open conductor systems?

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Answer 29A portable earth shall be applied in parallel to provide additional protection against induction charges.

Question 30Explain the result of a whipping effect be?

Answer 30Clamps may break loose.Isolated apparatus may become alive.People may be injured / killed.May cause short circuits.

Question 31Describe the term cable.

Answer 31A cable means a feeder, and includes the terminations.

Question 32.What are the requirements in regards with working with a Crane under an Overhead

Line?

Answer 32The only time when a crane may work under a line is when the line has been isolated in terms of regulation 1.65 “Safety Panel”.

Lesson 3TESTING AND ABNORMAL CONDITIONS

Question 1According to regulations 2.07.1 who is responsible for ensuring that the checking of

all phasing and high-voltage testing is carried out on new apparatus.

Answer 1The control officer.

Question 2Explain who is responsible for arranging, where necessary, for temporary settings of

relays on the first installation of apparatus?

Answer 2The control officer.

Question 3Explain at what points must suitable labels be affixed before any commissioning is

carried out?

Answer 3

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All apparatus and control panels must be suitably labelled.

Question 4Explain who is responsible for any earths that are deemed necessary on apparatus

not yet connected to the system?

Answer 4The person in charge of the work on the apparatus.

Question 5Explain at what stage does apparatus which is being installed become the

responsibility of the control officer?

Answer 5When connections can be made between the apparatus and the power system that will enable some part of the apparatus to be made alive.

Question 6According to the regulations when an apparatus is being installed, at what stage do

all earths on the panel come under the responsibility of the control officer?

Answer 6After the authorised person has advised the control officer of the position and all the required details of the apparatus, including the position and number of all earths which are at that time affixed to the apparatus.

Question 7Explain when it becomes necessary for carrying out testing to energise the

apparatus from the power system while it is in an abnormal condition, who must make the arrangements, and exactly who must he make them with?

Answer 7The department concerned must make special arrangements with the official in charge of the control centre so that the operating procedure can be agreed to beforehand.

Question 8Explain what is an abnormal condition according to regulation 5.09 testing of

equipment?1) Electrically abnormal2) Mechanically abnormal.

Answer 8If it is electrically in an abnormal condition; Regulation 5.09.1.1 shall be applied.having not all phases connected orhaving test instruments connected to the HV windings orhaving the protection disconnected orenergising the apparatus on an earthphasing incorrectAnswer 8 continues

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Regulation 5.09.1.2 shall be applied If it is mechanically in an abnormal condition;- the coupling is split- starting and stopping to balance fans or pumps- direction testing of motorA sanction for test (PSR) is then applied for. If work was limited to the HV side, regulation 5.09.1.1 shall be applied. To be done in accordance to a local procedure

Question 9Explain when it is necessary for tests to be carried out on apparatus, who removes

the earths and who supervises their removal?

Answer 9The operating as per the agreed test procedure shall be done by the appointed operator in conjunction with the responsible person.

Question 10State when earths are removed for testing, what is the responsible person’s

responsibility towards the workers?

Answer 10It shall be the responsibility of the responsible person for each test to warn workers and or temporarily withdraw the workers involved from the apparatus for the duration of the test.

Question 11State who must make the arrangement with the control officer for work on generating

plant at a Power Station?

Answer 11For work on generating plant at a power station, the official in charge shall make the necessary arrangements with the control officer for the plant to be taken out of commission.On completion of the work, this official shall notify the control officer that the plant is available for service. Should any delay arise in returning the plant at a pre-arranged time, this official shall immediately advise the control officer of the delay so that other arrangements may be made.

Question 12Name 3 duties does the official in charge perform, should something happen which

affects the safety of the plant during control of loading of power stations?

Answer 12* Shall be solely responsible for the handling and loading of each portion of the plant.* Shall immediately take the actions necessary to ensure the safety of plant.* Shall as soon as possible, notify the control officer of any change in loading or condition of the plant which may affect arrangements previously made.

Question 13

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Explain when the appointed operator has received a clearance of a work permit and on inspection finds that the apparatus is not ready for service, what action must be

taken?

Answer 13Inform the responsible person of the situation and issue another work permit so that the faults could be rectified immediately.

Question 14Give two reasons for withdrawing any one from a switch room before doing any

switching there.Answer 14* Persons could get a fright from the resulting noise, panic and possibly come into contact with live apparatus.* A switch or breaker could explode causing persons, trapped in a confined space, to sustain injuries or burns.

Question 15Explain what is meant by "in commission" and "out of commission"

Answer 15In commission means the state of apparatus that is available for immediate use, although it may not actually be in service.Out of commission means the state of any apparatus that has been taken out of service and is not available for immediate use.

Question 16Under regulation 5.09.1.1 Testing apparatus – being energised from the system?

Explain the procedure in the Power Station environment.

Answer 165.09.1.1 Testing apparatus – being energised from the system “Where it becomes necessary for the purpose of carrying out testing, to energise the apparatus from the system while such apparatus is in an abnormal condition the department concernedmust make special arrangements with the official in charge so that the operating procedure* can be agreed to beforehand. The existing work permit/s, on which work was performed, must be cleared.

A new work permit with the title “Test as per procedure* under Regulation 5.09.1.1” must then be issued affecting the tests to be carried out, indicating the state of isolations and earths required to carry out the tests. It shall be the responsibility of the responsible person for each test to warn workers and or temporarily withdraw the workers involved from the apparatus for the duration of the test.

The operating shall then be carried out in accordance with the agreed procedure* and in accordance with the regulations in so far as they apply.The operating as per the agreed test procedure shall be done by the appointed operator in conjunction with the responsible person.

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For the purpose of this regulation, an abnormal condition is one in which the apparatus is not in a condition to take normal load owing to jumpers being broken or to temporary connections having been made, protection settings not verified, any protection out of commission, temporary earths applied, or some similar reason.”

Question 17Under regulation 5.09.1.2 Testing apparatus – not being energised from the

system? Explain the procedure in the Power Station environment.

Answer 175.09.1.2 Testing apparatus – not being energised from the system

“Testing of apparatus as per this regulation may be done on the original work permit provided that the testing has been indicated on the scope of work and the risk assessment determines that it is safe. If the risk assessment indicates the need for a new work permit, this new work permit must be taken out under regulation 5.09.1.2.

If it is necessary, for the purpose of carrying out testing to energise the apparatus, from a source other than from the system, the department concerned must make special arrangements with the official in charge so that the test procedure can be agreed to before hand. The test procedure must be attached to the work permit.

It shall be the responsibility of the responsible person for each test to warn workers and or temporarily withdraw the workers involved from the apparatus for the duration of the test.

The operating shall then be carried out in accordance with the agreed procedure and in accordance with the regulations in so far as they apply. The operating as per the agreed test procedure shall be done by the appointed operator in conjunction with the responsible person.”

Question 18Explain when will apparatus be considered not to be part of the power system?

Answer 18Apparatus shall not be considered to be part of the power system when it has been disconnected from the power system by:

(c) either the removal of droppers or(d) By the opening of isolators. When opened, these isolators shall be locked with safety locks and the keys placed in the custody of a person not directly involved with the operating.

The person in charge of work shall be responsible for applying earths on apparatus that has been disconnected from the power system.

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Module 4

Lesson 1Duties and responsibilities of control officers

Question 1Name the three basic duties of the control officer?

Answer 1* Ensuring the safety of operators and the continuity of power supply customers.* Issuing instructions for:- Loading of plant.- Control of frequency and voltage.* Issuing instructions for operating in the section under their control.

Question 2Describe the term "control officer".

Answer 2A Person on duty at a control centre responsible for the general operation of the power system or section thereof.

Question 3State the reason why must the control officer issue operating instructions to power

station staff?

Answer 3To ensure they are aware of every isolation and earthing practice on the power system under their control and to prevent operators operating without instructions.

Question 4Before leaving, what information must the control officer going off duty give to the

person taking over the shift?

Answer 4All needful information as to the state of the power system and such other information as may be necessary in the proper discharge of duties.

Question 5Explain why a record of authorisations must be maintained in each control centre?

Answer 5The control officer on duty must ensure that anyone requesting permission to operate is authorised to carry out the operating requests.

Question 6State the area for which the Local Control Officer is responsible for on a Power

Station?

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Answer 6Auxiliary apparatus at the power station.

Question 7Name the two conditions under which a temporary local control centre can be

established.

Answer 7* The control officer has given permission.* Every possible effort has been made to contact the control officer, but has failed.

Question 8According to the regulation the control officer is responsible for keeping of records.

Explain your answer.

Answer 8* Time and details of all operating with the names of persons who carry out such operating.* Emergency switching time with the names of persons who have carried out these operations.* Each control centre, except for National Control, for the section of the power system under its jurisdiction, of the names and telephone numbers of all persons authorised for operating and the extent of their authorisation.

Question 9Explain who may set up a temporary local control centre?

Answer 9A person specifically authorised for this purpose who will take over the duties of the control officer.

Question 10State three duties of a person who has set up a temporary local control centre.

Answer 10All authorised persons out operating in the area affected have beenadvised that a temporary local control centre is to be established.

All switching, linking and earthing operations must be logged during thisperiod, and when communications or normal conditions are restored, thecontrol officer must be given full details of this operating as well as thepositions of all breakers, isolators and earthing gear at the time ofhandling back to the control officer.

The person acting as local control officer shall be responsible for theoperation of such local section of the power system in accordance withthese regulations, but shall not personally carry out any operating.

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Lesson 2Use of operating instruction form

Question 1The person doing the operating shall take the operating instruction form to the place

where the operations are to be carried out. What action/s must be taken before commencing operating?

Answer 1* Instructions shall be read by the authorised person carrying out the operation.* Check that the apparatus and the intended operation correspond with the written instructions.

Question 2"All operating instructions from the control officer shall be given in detail, without

abbreviation, stating .............". Name the three things, which must be stated?

Answer 2* The name of the apparatus.* The nature of the operation.* The time of confirmation of the instruction.

Question 3Explain when an operating instruction must be cancelled?

Answer 3* When the instructions were incorrectly pre-written or altered.* Changes in the running arrangement of a power station.* Any circumstances that could delay or prevent the carrying out of an instruction, such as:- Defect in apparatus.- Operators personal reason.

Question 4(i) State the purpose of the operating instruction form?(ii) Explain what is an operating instruction form?

Answer 4(i) To ensure the correct sequence of operating will be followed after two or more persons have agreed on the (correct) operating procedure.(ii) It is the printed form used for recording instructions issued by the control officer for operating to be carried out on electrical apparatus.

Question 5Give three practical advantages of the operating instruction form.

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Answer 5* No need to rely on memory alone.* Reduces the chances of errors, as operations are set down in sequence and ticked off as completed.* Provides a quick reference.

Question 6State the minimum duration and why must the completed operating instruction form

be retained?

Answer 6Records of all operating carried out must be kept for one year, for any enquiries that may arise.

Question 7Describe what shall be done on completion of any operating instruction form?

Answer 7* The time shall be recorded.* Immediately report back to the control officer.* The form shall be filed.

Question 8State when does operating end?

Answer 8Once the completed operation has been reported to the control officer and the operating diagram has been altered to indicate the correct state of apparatus.

Question 9Explain what happens to the operating instruction form while the appointed operator

is doing the operating?

Answer 9The form is taken with the appointed operator to the work place.

Question 10Explain the reason for communication between the control officer and the person

doing the operating?

Answer 10* Ensure the correct operating is done in the correct sequence.* The control officer and the appointed operator are aware of the state of the apparatus at all times.

Question 11State the two operations to the regulations which allow pre-authorised operating

instruction to be given to a power station?

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Answer 11* Synchronising of a generator.* Taking a generator off load.

Question 12(i) Pre-authorised synchronising will not be permitted at Frequencies above .... Hz.(ii) Pre-authorised generator shut-down will not be permitted At frequencies below .... Hz.

Answer 12(i) 50,3 Hz.(ii) 49,7 Hz.

Question 13Name the conditions that could delay the synchronising or loading of a generator?

Answer 13Steam and/or metal temperatures, differential expansions, shaft eccentricity may be critical.

Question 14Explain the use of an operating diagram? (Reg. 2.08).

Answer 14To indicate the operating position and the correct state of all apparatus.

Question 15State how shall all operating instructions be given by the control officer?

Answer 15In detail without any abbreviations.

Question 16May the operating instructions be pre-written? If your answer is yes, state who may pre-write them. If your answer is no, what is the normal procedure to be followed?

Answer 16Yes, by:* The appointed operator doing the operating.* Person authorised to transmit operating instructions.

Question 17Explain who is to sign the operating instruction form after it has been written?

Answer 17The appointed operator who received the instructions and is going to do the operating (if applicable the trainee as well).

Question 18Give four advantages of using an operating diagram (as defined).

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Answer 18* At all times you can see the state of breakers, switches and isolators and the position of earths throughout the section of the power system.* Useful for planning operating in advance.* Training aid and assists in developing diagnostic ability.* Always promotes correct and safe operating.* During a mishap it enables another person to assess the situation immediately and to take corrective action.

Question 19Explain the procedure that is to be followed in the case of a trainee doing operating?

Answer 19The trainee and appointed operator must check independently each for themselves that the intended operating can in fact be carried out with safety.

Question 20Explain when it is impossible for an authorised person to obtain direct

communication with the control officer, what must be done to obtain an operating instruction?

Answer 20Using a third person who must be a person authorised for operating or a person who has been authorised to transmit operating instructions.

Question 21State when the operating diagram must be updated?

Answer 21On completion of any operation.

Question 22Explain which messages on any communication system must always be given

preference?Answer 22Messages to and from the control officer.

Question 23Who is responsible for updating the operating diagram board?

Answer 23Control officer

Question 24Describe the term operating diagram

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Answer 24Means the permanent diagram in control centre, or power station control room that indicates the operating state and position of all apparatus.

Question 25List the steps to be followed when operating under an operating instruction.

Question 25* Control officer gives instruction (no abbreviations).* Appointed operator writes instruction on the form using a separate line for each entry. (Standard abbreviations may be used when writing).

Note: In order to save time, the instruction may be prewritten.* Appointed operator reads instruction back to the control officer.* Control officer confirms or corrects.* Appointed operator signs the form date and time.* Operating instruction form taken by appointed operator to the workplace.* Appointed operator reads instruction and checks that it is the right apparatus.* Appointed operator carries out instructions, ticking off each step as completed.* On completion, the operation is reported to the control officer with immediate effect stating time.

Lesson 3ISOLATING

Question 1In order to control the system voltage, it is often necessary for the control officer to

carry out switching. State what must be switched in or out?

Answer 1Switching in or out of capacitor and reactors banks at un-attended stations.

Question 2Under what circumstances may more than one appointed operator perform operating

on the same apparatus?

Answer 2When it is necessary to operate at two or more points situated some distance apart.

Question 3Explain when may the earthing operation commence, if more than one appointed

operator performs the operating?

Answer 3The control officer shall authorise the earthing operations only when isolation has been completed at all points.

Question 4State the minimum earthing requirements for a line or section of a line, which has

been isolated from all points of supply, before starting the work .

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Answer 4At least one earth shall be applied to the line or section of line between the point of isolation and the first place of work. Authorised working earths to be applied as needed.

Question 5Explain the procedure to be followed while busy with operating when handing over

shift.

Answer 5Where continuous shift work is in operation the appointed operator may hand over the shift to the appointed operator relieving him provided that all operating instructions issued by the control officer to the off-going appointed operator have been fully carried out.

Question 6Explain under which conditions a crane may work under an overhead line.

Answer 6The only time when a crane may work under a line is when the line has been isolated in terms of regulation 1.65 “Safety Panel"

Lesson 4 EXCEPTIONS TO THE GENERAL OPERATING PROCEDURE

Question 1Name the exceptions to the general operating procedure Reg 2.01.

Answer 1* Emergency switching.* Operating on dead-ended feeders and auxiliary apparatus in power stations excluded by means of area operating regulations.

Question 2Explain when will emergency switching be carried out?

Answer 2In cases where lives are in danger or apparatus can be damaged.

Question 3Explain who may perform emergency switching?

Answer 3Any person may perform emergency switching.

Question 4Explain why do we have exceptions to the general operating procedure?

Answer 4To allow for circumstances beyond the control of the control officer.

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Question 5After emergency switching has been carried out, Explain who must be informed and

why?

Answer 5The control officer must be informed as soon as possible after emergency switching was carried out, because a record must be kept of the operating, the time and details as well as the name of the person who carried out the emergency switching.

Question 6Does auxiliary apparatus on a power station fall under the control officer?

Motivate your answer.

Answer 6No, they are not directly connected to the power system.

Question 7Describe the abnormal conditions that must be reported to the control officer?

Answer 7Emergency switching. Adverse weather conditions, veld fires, unit trip, load loss.

Question 8Explain the process to restore loss of supply in the event of failure or absence of

communications. (Reg 6.04)

Answer 8Authorised persons may, at their discretion, close breakers in order to resume supply, provided that where two or more feeders enter a station only the breakers of feeders originating from one point may be closed without permission from the control officer.

Question 9Under what conditions may the control officer interrupt calls or messages?

Answer 9During periods of abnormal system conditions.

Question 10A station which houses the breaker that controls a line on which live work is to be done. The control officer is about to hand over the line to the authorised person in charge of the live work. Before the control officer does this, what must be done?

Name them.

Answer 10Live work warning notices to be affixed to all control panels of breakers controlling the supplyAll auto re-closing features on these breakers to be switched off or otherwise made inoperative.

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Question 11Explain what is an earthing label and when is it used?

Answer 11An earthing label is the printed form used at power stations for affixing to control panels to indicate that the apparatus has been earthed stating the number and position of all earths and the work permit number.

Question 12Explain when and by whom an earthing label may be removed?

Answer 12The earthing label shall be removed by the appointed operator when the operation of removing all the earths to which it relates is completed.

APPENDIX 6Module 1

KEY LEARNING POINTSTHEORY

1 Alive or live means electrically connected to the power system or electrically charged.

2 Apparatus means any generator, transformer, motor, switchgear, isolator, feeder, electrostatic precipitator or any other high-voltage plant installed in a station or on a feeder.

3 Isolate or Isolating or Isolated refers to the disconnection of the apparatus to form an air gap from all possible sources of electrical potential.

4 Isolation may be obtained by:(a) the opening and removal of fuses(b) the opening of isolators(c) the removal of jumpers/droppers(d) the opening of air break switches(e) the racking out of truck-type switchgear(f) the immobilisation of breakers having visible contact separation, and not fitted with grading capacitors

5 Dead means that any apparatus so described is at or about zero potential and disconnected or isolated from any live power system. Rotating plant shall not regarded as dead until it is stationary or is being slowly rotated by means of barring gear and is not excited.

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6 Isolator means a device provided for the purpose of isolating apparatus from the source of electrical potential.

7 Breaker means a device designed to make or break electric current under both normal and fault conditions.

8 Switch means a device, other than a breaker, designed for making or breaking a rated flow of electric current. The term includes air break switches or weight-operated disconnects and similar devices.

9 Earthing or earthed means the connecting of apparatus electrically to the general mass of earth in such a manner that it will ensure an immediate safe discharge of electrical energy at all times.

10 Live chamber means any chamber, enclosure or any situation in which inadvertent human contact with conductors or live parts of electrical apparatus working at high voltage is possible from ground or floor level.

11 Prohibited area means an enclosed area in which live conductors or live parts of electrical apparatus working at high voltage is accessible, but situated in such a position that inadvertent human contact is not possible from ground or floor level.

12 Restricted area means an enclosed area that is neither a live chamber nor a prohibited area as defined, and that is enclosed for the purpose of power system security and the safety of personnel.

13 Reg. 3.02 states that: Only authorised persons or persons under supervision of an authorised person may enter a live chamber

14 Supervision or supervise refers to the overseeing of the actions of a person or persons so as to prevent any act that could be dangerous or in contravention of these regulations.

15 Work or Working or Worked refers to all physical activities in connection with apparatus, excluding operating and other non-dangerous activities that will not affect the health and safety of workers or the safe operation of apparatus.

16 Reg 3.03. States that: "A person who has not been authorised to enter a prohibited area shall be allowed access to the ground level only of a prohibited area if he is under the supervision of an authorised person or if he is working under a work permit.

He shall remain on ground level unless the working area is suitable demarcated by means of barriers to ensure that inadvertent human contact with live apparatus adjacent to or above the demarcated area is not possible from within the barriers. In addition, a work permit shall be issued detailing the apparatus on which he is required to work, unless he is working on the distribution system under the supervision of an authorised person in accordance with reg. 8.02.7

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If a section of a prohibited area and the access to that section in which work is to be carried out, is effectively segregated so as to prevent dangerous approach to live apparatus, such section shall no longer constitute a prohibited area and no supervision by an authorised person shall be required".

17 Reg 3.04. States that: "Access to restricted areas shall be allowed only to persons who have obtained permission, through an authorised method".

18 Emergency switching means the opening of only such breakers or switches as may be necessary to avoid imminent danger to life or damage to apparatus.

Module 2KEY LEARNING POINTS

THEORY1 Apparatus means any generator, transformer, motor, switchgear, isolator, feeder, electrostatic precipitator or any other high-voltage plant installed in a station or on a feeder.

2 Appointed operator in a power station means an employee or a non-employee, who is authorised to do operating and is deemed to be an authorised person in terms of these regulations

3 Responsible person means a person, whether an employee or a non-employee, who has been authorised to be responsible for ensuring that the work on the apparatus covered by a work permit can be, carried out safely and within the terms of these regulations.

4 Authorise or Authorised refers to the giving of permission in writing to perform specific duties all responsibilities in terms of these regulations. Authorisation remains valid for a maximum period of three years.

5 Supervision or supervise refers to the overseeing of the actions of a person or persons so as to prevent any act that could be dangerous or in contravention of these regulations.

6 Work or Working or Worked refers to all physical activities in connection with apparatus, excluding operating and other non-dangerous activities that will not affect the health and safety of workers or the safe operation of the apparatus.

7 Reg. 8.01.9 states that: "The responsible person shall explain the nature of the work covered by the work permit and the dangers as per the pre-work checklist, attached thereto to all the workers who will be engaged in this work, and shall thencomplete the workers register. The workers register shall be current at all times.If work extends over a period of time especially more than one day or shift, on completion of work or at the end of shift, the workers register must be signed. When the work resumes on the next day or the next shift, a new workers register mustbe signed. This is also applicable when a person is delegated from one Job/Work to another. This regulation shall be read in conjunction with regulation 5.06. The “test before touch” (GGD1221) principle must be adhered to.”

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8 Reg. 8.01.8 states that: "When it is necessary for work to be done on apparatus at a power station in more than one chamber on the same circuit a separate work permit shall be issued for the work in each separate chamber”.

9 Operating means switching, linking, safety testing and earthing.

Module 3KEY LEARNING POINTS

THEORY

1 Alive or live means electrically connected to the power system and or electrically charged.

2 Apparatus means any generator, transformer, motor, switchgear, isolator, feeder, electrostatic precipitator or any other high voltage plant installed in a station or on a feeder.

3 Isolator means a device provided for the purpose of isolating apparatus from the source of electrical potential.

4 Switch means a device, other than a breaker, designed for making or breaking a rated flow of electric current. The term includes air break switches or weight-operated disconnects and similar devices.

5 Breaker or Circuit Breaker means a device designed to make or break electric current under both normal and fault conditions.

6 Reg. 2.07 Making apparatus alive on first installation or after alteration or repairs states that:

Reg. 2.07.1 “Any apparatus on first installation or after alterations or repairs, shall not be placed in commission without prior handing over for service to the control officer by an official of the department concerned. No commissioning shall be carried out unless all apparatus and control panels are suitably labelled.

The control officer shall ensure that all necessary high-voltage testing of apparatus and the checking of all phasing, synchronising equipment and protection equipment is carried out on first commissioning or after alterations or repairs.

A note to this effect, including the names and designations of persons responsible for such tests shall be logged by the control centre concerned.

The control officer shall be responsible for arranging, where necessary, for temporary settings of relays on first installation of apparatus, and thereafter for the final settings of the relays for normal working conditions".

Reg. 2.07.2 Apparatus shall not be considered to be part of the power system when it has been disconnected from the power system by:

a) either the removal of droppers or

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b) By the opening of isolators. When opened, these isolators shall be locked with safety locks and the keys placed in the custody of a person not directly involved with the operating.

The person in charge of work shall be responsible for applying earths on apparatus that has been disconnected from the power system.

Reg. 2.07.3 “Apparatus that is being installed does not fall under the responsibility of the control officer until the installation reaches the stage at which the making of connections between the apparatus and the power system will enable some part of the apparatus to be made alive.

The control officer shall then immediately be advised of the position by the authorised person who shall give the control officer all required details of the apparatus, including the number and position of any earths which are at that time affixed to the apparatus.

From this stage the control officer shall be responsible for all earths on the apparatus being commissioned and the procedure detailed in section 5 shall be followed."

7) 5.09.1.1 Testing apparatus – being energised from the system

Where it becomes necessary for the purpose of carrying out testing, to energise the apparatus from the system while such apparatus is in an abnormal condition the department concerned must make special arrangements with the official in charge so that the operating procedure* can be agreed to beforehand.

The existing work permit/s, on which work was performed, must be cleared. A new work permit with the title “Test as per procedure* under Regulation 5.09.1.1” must then be issued affecting the tests to be carried out, indicating the state of isolations and earths required to carry out the tests.

It shall be the responsibility of the responsible person for each test to warn workers and or temporarily withdraw the workers involved from the apparatus for the duration of the test.

The operating shall then be carried out in accordance with the agreed procedure* and in accordance with the regulations in so far as they apply.The operating as per the agreed test procedure shall be done by the appointed operator in conjunction with the responsible person.

For the purpose of this regulation, an abnormal condition is one in which the apparatus is not in a condition to take normal load owing to jumpers being broken or to temporary connections having been made, protection settings not verified, any protection out of commission, temporary earths applied, or some similar reason.

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8) 5.09.1.2 Testing apparatus – not being energised from the system

Testing of apparatus as per this regulation may be done on the original work permit provided that the testing has been indicated on the scope of work and the risk assessment determines that it is safe. If the risk assessment indicates the need for a new work permit, this new work permit must be taken out under regulation 5.09.1.2.

If it is necessary, for the purpose of carrying out testing to energise the apparatus, from a source other than from the system, the department concerned must make special arrangements with the official in charge so that the test procedure can be agreed to beforehand. The test procedure must be attached to the work permit.

It shall be the responsibility of the responsible person for each test to warn workers and or temporarily withdraw the workers involved from the apparatus for the duration of the test.

The operating shall then be carried out in accordance with the agreed procedure and in accordance with the regulations in so far as they apply.The operating as per the agreed test procedure shall be done by the appointed operator in conjunction with the responsible person.

9) Operate or Operating means switching, linking. Safety testing and earthing.

10 Auxiliary apparatus means the bus bars and apparatus at a station, which are supplied by standby generators or the secondary sides of station, unit or earthing transformers or from the tertiary windings of main transformers.

11 Equipotential zone means a safe work area created to ensure that any two or more conducting parts that can be touched by a person simultaneously are bonded together by approved earthing leads to ensure a zone of equal potential between different parts of the working area.

APPENDIX 7KEY LEARNING POINTS

KLP Module 1:

1 What is by definition Alive or Live? a) Electrically connected.b) Linked to the system.c) Electrically energised.d) Electrically connected to the power system or electrically charged.

2 What is by definition Apparatus? a) Busbar, conductor.b) Switchgear, isolator.c) Control switch, panel.d) Feeder, transformer.e) All the answers are correct.

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3 What is meant by isolate? a) Disconnect apparatus from any live electrical energy.b) An air gap is formed.c) Apparatus disconnected by means of opening switches.d) Apparatus disconnected from all possible sources of electrical potential.e) Apparatus disconnected from all possible source of electrical energy.

4 How may isolation be obtained? a) Racking out of truck-type switchgear.b) Opening of isolators.c) Lock off fuses.d) Opening/removal of fuses.e) Opening of circuit breakersf) Opening of air break switches.

5 What is by definition Dead? a) Disconnected or isolated from any live power system.b) Plus minus zero potential.c) At or about zero potential.d) Not linked to a power system.e) Plant rotating slowly and not charged.f) Plant stationary, rotating slowly on barring gear and not excited.

6 Isolato r means a device for the: a) Purpose of disconnecting apparatus from a source.b) Purpose of make or break a circuit.c) Purpose of isolating apparatus from the source ofelectrical potential.

7 Breaker means a device designed to: a) Connect or disconnect a circuit.b) Make or break a circuit under any condition.c) Make or break electric current, under both normal and fault conditions.

8 A switch is designed to: a) Make or break a circuit.b) Make or break a limit flow of current.c) Make or break a rated flow of electric current.

9 What is meant by Prohibited area? a) Where live high voltage conductors or live parts of high voltage electrical apparatus can be touched from ground/floor level.b) Where contact with live conductors and live electrical apparatus working at high voltage is not possible from ground/floor level.c) Where human beings can touch live electrical apparatus and conductors from ground/floor level.

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10 What is by definition a Restricted area? a) Same as a prohibited area.b) Fenced off for power system security and safety of plant.c) Enclosed for the purpose of power system security and safety of personnel.d) Enclosed for the purpose of power system protection and the safety of personnel.

11 What is the procedure for access to a live chamber in Generation. a) Work permit in force.b) No person in Generation is allowed into a Live Chamber under any circumstances.c) Under supervision of an appointed person.d) Under supervision of a responsible person.e) Must be an authorised person.f) Must be a responsible person.g) Under supervision of an authorised person.

12 What is by definition Supervision or Supervise? a) The overseeing of the actions of workers to prevent accidents.b) The overseeing of the work to ensure it is done correctly.c) The overseeing of the actions of a person or persons so as to prevent any act that could be dangerous or in contravention of the regulations.d) One of the duties of the responsible person.

13 Who is responsible for the safety of the workers regarding Supervision? a) Person in charge of department.b) Responsible person.c) Skilled person.d) Qualified person.e) The person responsible for supervision

14 State what is by definition work? a) All physical activities in connection with apparatus.b) Operating activities.c) Non - dangerous activities that will not affect the health and safety of workers or the safe operation of the apparatus.d) An activity that does not require isolation.e) Activities carried out personally by an authorised person.

15 Under what circumstances may an unauthorised person enter a prohibited area in terms of Reg. 3.03?a) Ground level only - LAR in place.b) Above ground level - work permit and no supervision required because it is barricaded.c) Above ground level - work permit, supervision and area barricaded.d) Ground level only - work permit in force.e) Ground level only - work permit in force or supervision required by skilled person.f) Under supervision of an authorised person.

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16 How may access be gained to a Restricted area? a) Using a work permit.b) Through an authorised method.c) Using a LAR.

17 What is by definition Emergency switching? a) Opening and closing of breakers.b) Opening of only such breakers and switches.c) Opening and closing of isolators.d) To avoid imminent danger to life or damage to apparatus.

KLP Module 2:

1 What is by definition apparatus? a) Busbar, conductor.b) Switchgear, isolator.c) Control switch, panel.d) Feeder, transformer.e) All the answers are correct

2 What is an Appointed operator? a) Person authorised to do work.b) Person authorised to do switching and linking.c) Person authorised to do operating.d) Authorised person in terms of these regulations.3 What is a Responsible person? a) Only an employeeb) A Person who has been authorised.c) To do work safely.d) To be responsible to ensure that work is carried out safely.

4 What, does Authorise or Authorised refer to? a) A person who is authorised in terms of the regulations.b) A person who has received written permission.c) A person who has been authorised.d) A person who has permission to perform specific duties and responsibilities in terms of the regulations.

5 What is by definition Supervision or Supervise? a) The overseeing of the actions of workers to prevent accidents.b) The overseeing of the work to ensure it is done correctly.c) The overseeing of the actions of person or persons so as to prevent any act that could be dangerous or in contravention of these regulations.d) None of the duties mentioned above.

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6 What does work refer to? a) All physical activities in connection with apparatus.b) Operating activities.c) Non-dangerous activities which will not affect the health and safety of workers or the safe operation of apparatus.d) An activity that does not require isolation.e) Activities carried out by an authorised person.

7 What must be done in terms of the workers register as per Reg8.01.9? a) Responsible person must complete workers register.b) Workers enter their names onto workers register.c) Skilled person explains work and dangers to workers.d) Responsible person explains work and dangers as per the pre-work checklist to workers.e) Workers register to be current at all times.f) Workers register to be completed once and only to be sign off when work is completed.

8 When it is necessary to carry out work on apparatus at a power station in more than one chamber but on the same circuit how many work permits are required. (Reg 8.01.8)?a) One permit for the circuit.b) Separate permits for each separate chamber.c) Amount of permits does not matter.

9 What is by definition operating? a) Opening and closing of breakers.b) Switching, linking, safety testing and earthing.c) Opening and closing of isolators.d) Earthing operations only.

KLP Module 3:

1 What is by definition Alive or Live? a) Electrically connected.b) Linked to the system.c) Electrically energised.d) Electrically connected to a power system or electrically charged.

2 What is by definition Apparatus? a) Busbar, conductor.b) Switchgear, isolator.c) Control switch, panel.d) Feeder, transformer.e) All the answers are correct.

3 Isolator means a device for: a) Purposes of disconnect apparatus from a source.b) Purpose of make or break a circuit.c) Purpose of isolating apparatus from the source of electrical potential.

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4 What is by definition a switch? a) Same as a breaker.b) Other than a breaker.c) Includes air break switches.d) Also an isolator.e) Make or break a circuit.f) Make or break a limit flow or current.g) Make or break a rated flow of electric current.

5 Breaker or Circuit Breaker means a device designed to: a) Connect or disconnect a circuit.b) Make or break a circuit under any conditions.c) Make or break electric current under both normal and fault conditions.

6 State the requirements in terms of Reg 2.07 that must be in place before making apparatus alive on first installation or after alterations or repairs.a) Apparatus and Control panels suitably marked.b) Handing over for service by Operating manager.c) Commissioning to arrange for temporary settings.d) Control officer to arrange for temporary relay settings and permanent settings.e) Handing over for service by official of department concerned.f) PTM to ensure high voltage testing and checking of phasing and protection equipment is carried out.g) Control officer ensures high voltage testing of apparatus and checking of all phases and protection equipment is carried out.h) Apparatus and control panels to be suitably labelled.

7 What has to be done in order to test apparatus in terms of Reg 5.09.1.1? Energised from the system.a) The local control officer issues the instructions to isolate and earth apparatus.b) Department concerned makes special arrangements with the official in charge.c) Operating procedure to be agreed on beforehandd) A work permit must be issued affecting the tests to be carried out and the state of isolations and earths required to carry out the testse) Existing work permit, on which work was performed, must be cleared.f) The operating shall then be carried out in accordance with the agreed procedure and in accordance with the regulations.

8 If it is necessary to carry out testing of apparatus not energized from the system, what must be done for compliance to Reg 5.09.1.2?a) Agreed operating to be carried out in accordance with theprocedure.b) Local regulations to be in place.c) Commissioning makes arrangements with control officer.d) Operating procedure to be in place and agreed beforehand.e) Responsible Person to warn and withdraw workersf) Department concerned makes arrangements with official in charge.

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9 What is by definition Operating? a) Opening and closing of breakers.b) Switching, linking, safety testing and earthing.c) Opening and closing of isolators.d) Earthing operations.

10 What is by definition Auxiliary apparatus? a) Generators and or feeders.b) Busbars and apparatus at a station which are supplied by standby generators or the secondary sides of station, unit and earthing transformers or from the tertiary windings of main transformers.c) All apparatus under the control of the L.C.O.d) Transformers only.

11 What is an equipotential zone? a) Created safe work area.b) Two or more conducting parts that can be simultaneously touched by a person.c) Effectively earthed to provide a safe environment.d) Approved earthing leads bond the conducting parts together.e) The parts are joined together to create a zone of equal potential.f) Ensures a zone of equal potential between different parts of the working area.

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