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Chapter 1: IntroductionChapter 2: Devices & ComponentsChapter 3: Direct-On-Line (DOL)

Chapter 4: Forward/Reverse (Fwd/Rev)Chapter 5: Star-DeltaChapter 6: Autotransformer

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Main Chapters of Motor Control

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Refer to teaching plan file ( micro word)

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Overall Teaching Plan

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Make sure environment around workplace is clean andsystematic before and after work.Wear suitable clothing, not too tight and not tooloose. Wear shoe having thick and all round sew solewhen doing wiring work.Wearing slipper is strictly prohibited .Equipment used must in good and perfect condition . Ifnot, report to officer in charge. All equipment must be

kept at right and safe place so that it is easy to look forespecially during emergency.After use, the equipment must be kept at its originalplace .

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Safety Precaution in Labs

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5

Please wear shoes in labs!

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Nobody is allowed to make joke or playing sharpinstrument or object with friend while doing wiring work.Make sure the cable/conductor used fulfill its size (rating) and having suitable insulation .Make sure every electrical installation have effectiveearthing and avoid it from rust.After using electrical machine, it must be switch off.Any addition of circuit must be avoided unless there ispermission from officer in charge.

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Safety Precaution in Labs (cont.)

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Wearing slipper is strictly prohibitedNo jeansNo long hair for manNo camerasNo too tight or too loose clothingNo round neck t-shirtJacket is strongly recommendedAttendance is compulsory

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Others Reminder

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Personal ProtectiveEquipment (PPE)

Wear PersonalProtectiveEquipment (PPE)when necessary

Example: Safety shoes Safety goggles Ear plugs Face mask Safety helmet Overall

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Hazard of CurrentCurr ent E ffect

Safe CurrentValues

1 mA or less

1 mA to 8 mA

Causes no sensation - not felt.

Sensation of shock, not painful;Individual can let go at will sincemuscular control is not lost.

Unsafe currentvalues

8 mA to 15 mA

15 mA to 20mA

50 mA to 100mA

100 mA to 200mA

200 mA andover

Painful shock; individual can let go at will sincemuscular control is not lost.

Painful shock; control of adjacent muscles lost;victim can not let go.

Ventricular fibrillation - a heart condition thatcan result in death - is possible.

Ventricular fibrillation occurs.

Severe burns, severe muscular contractions - sosevere that chest muscles clamp the heart andstop it for the duration of the shock. ( Thisprevents ventricular fibrillation) .

It's not the voltage but the current that cause hazards!

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1. Read carefully and understand the circuit drawingand installation manual before start works

2. Design both main/power circuit and control circuit3. Arrange the tools and components properly in

their places4. Wire up the main/power circuit at first5. Then, wire up the control circuit6. Do the connectivity test, troubleshoot if necessary

before apply the power supply7. Get permission from instructor and apply power

supply.

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Good Practice in Motor Control Works