User Guide for THEIA Central Inverters

357104.013

Solar Grid-Tie Inverters20kW to 500kW

THEIA Central Inverters

User Guide

2 User Guide THEIA Central Inverters 357104.013, Issue 3.0, 2010 Jul

Information in this document is subject to change without notice and does not represent a commitment on the part of Eltek Valere. No part of this document may be reproduced or transmitted in any form or by any means — electronic or mechanical, including photocopying and recording — for any purpose without the explicit written permission of Eltek Valere.

Copyright ©: Eltek Valere, 2010

357104.013 Issue 3.0, 2010 Jul

Published 2010-07-23

GpF

NS-EN ISO 14001 Certified

Certificate No: 11276-2007-AE-NOR-NA

NS-EN ISO 9001 Certified

Certificate No:4072-2007-AQ-NOR-NA

User Guide THEIA Central Inverters 357104.013, Issue 3.0, 2010 Jul 3

Table of Contents 1. General Information .................................................................... 5

Introduction ..................................................................................................... 5 Symbols Used ................................................................................................. 5 Applicability ..................................................................................................... 6

2. Contact Information .................................................................... 7

3. Limitation of Liability .................................................................. 8

4. Regulations and Safety Warnings ............................................. 9 Nominal Data ................................................................................................ 10

5. General Description of Inverter ................................................ 11 Basic Data on the Photovoltaic System ........................................................ 11 Description of the System ............................................................................. 12

Type ................................................................................................................ 12 Operating Conditions ...................................................................................... 12 Operating Modes ............................................................................................. 12

Controls and Operating Mechanisms ............................................................ 13 Isolator Switches (DC input and AC output) .................................................... 13 Inverter “ON/OFF” Selector Switch ................................................................. 13 Emergency Power Off (EPO) push-button ...................................................... 14 LCD Control Panel .......................................................................................... 14

6. Front Panel ................................................................................. 16 Flow Chart .................................................................................................... 17 Status LEDS ................................................................................................. 17 LED Bar ........................................................................................................ 18 Function Keys ............................................................................................... 18

7. Managing the LCD Panel .......................................................... 19 Main Screen .................................................................................................. 19 Main Menus .................................................................................................. 19 Modifying the Operating Mode ...................................................................... 20

STAND-BY Mode ............................................................................................ 20 MANUAL CURRENT Mode ............................................................................. 20 MPPT mode .................................................................................................... 21

Measures Display ......................................................................................... 23 Statistics Display ........................................................................................... 24 Basic Diagnostics .......................................................................................... 25

Display of Alarm Histories ............................................................................... 26 List of Alarms and States ................................................................................ 27 Resetting the EPO Alarm ................................................................................ 28

8. Programming of Parameters .................................................... 29 Setting the Date and Time ............................................................................ 31 Setting MPPT parameters (Advanced setting) ............................................. 31

MPPT Rate ...................................................................................................... 31 Voltage Step .................................................................................................... 31

Setting Starting Voltage (Advanced Setting) ................................................ 32 Setting Stand-By Time (Advanced Setting) .................................................. 32 Setting Nightly Power Off (Advanced Setting) ............................................. 33 Setting Modbus Parameters (Advanced Setting) .......................................... 33 Setting Grid Tolerance (Advanced setting) .................................................. 34


Grid Positive Tolerance .................................................................................. 34 Grid Negative Tolerance ................................................................................. 34

Other Parameters ......................................................................................... 35 Resetting the System ................................................................................... 36 Deleting History Data (Advanced Setting) .................................................... 36 Resetting the Alarm History ......................................................................... 36

9. System Information ................................................................... 37 Information on Service ................................................................................. 38

10. Failures and Alarms .................................................................. 39 Definition of Operating States ...................................................................... 40 Troubleshooting ........................................................................................... 42

11. Maintenance .............................................................................. 49 Maintenance Programme ............................................................................. 49

Cleaning Ventilation Grills And Air Filters ....................................................... 50 Cleaning Control and Power Electronics ........................................................ 51 Checking Power Cable Terminals .................................................................. 51 Visual Check of Magnetic Parts ...................................................................... 51 Checking Fan Operation ................................................................................. 51 Checking Control Devices (DC and AC Isolators Switches) .......................... 52 Checking Protective Fuses ............................................................................. 52 Checking Generator Device ............................................................................ 52 Checking Surge Arresters ............................................................................... 52 Checking the Mechanical Parts of the Cabinet ............................................... 53


1. General Information

Introduction Thank you for choosing an Eltek Valere Renewable Energy product for the power conversion

needs of your photovoltaic field. This section of manual contains general information on the symbols used in the THEIA Central Solar Inverter documentation. It also gives provides contact information and important notes concerning responsibility and liability.

Symbols Used In order to minimise the risk to people and property, the following symbols have been used to

indicate potential hazards and to highlight important information.

DANGER

“DANGER” notices give characteristics and instructions that are fundamental for the safety of people. Ignoring these notices may cause severe injury or even death.

MAXIMUM ATTENTION

“MAXIMUM ATTENTION” notices give characteristics and instructions that are fundamental for the safety of people. Ignoring these notices may cause injury.

WARNING

“WARNING” notices give characteristics and instructions that are important for the protection of property. Ignoring these notices can lead to damage of materials.

NOTE

“NOTE” notices give characteristics and instructions that are important for the operation of the device and to help ensure optimum performance.


Applicability The instructions given in this installation manual are applicable to the complete range of THEIA

Central solar inverters, as indicated hereinafter.

• THEIA Central 20kW TX

• THEIA Central 20kW TL












Acronyms used

• TX indicates that there is an output transformer inside the inverter cabinet.

• TL indicates that there is no output transformer, which may be required to be provided separately in order for the inverter to interface correctly with the AC network.

Storing the Documentation

This manual and all other product support documentation must be kept and, if possible, made accessible to the personnel in the immediate vicinity of the THEIA Central inverter.

Additional Information

If the information given in this manual is not sufficiently exhaustive, please contact the device manufacturer, whose details are available in the “Contacts” section.


2. Contact Information For any information regarding the THEIA Central solar inverter, please contact Eltek Valere,

whose headquarters are based at:

Eltek Valere AS.

Gråterudveien 8

3036 Drammen

Norway

Phone: +47 3220 3200

Fax: +47 3220 3210

or any local Eltek Valere office or subsidiary, a list of which can be found at: http://www.eltekvalere.com For help with technical problems or for information concerning device use and maintenance,

please contact Technical Support Services, specifying the following data:

• Type of device and its nominal power.

• Serial number

• Error code (if applicable)


3. Limitation of Liability All information contained in this documentation is the exclusive property of Eltek Valere AS.

Prior written approval is required from Eltek Valere AS before any, or all, of this document may be reproduced or information contained within is disclosed.

• This manual constitutes an integral part of the product technical support documentation. Read the warnings contained in it carefully as they provide important indications concerning safe usage.

• The equipment must be exclusively used for the purposes for which it was expressly designed. Any other use is considered improper and therefore hazardous. The manufacturer cannot be held responsible for possible injury or damages arising from improper, erroneous or unreasonable usage.

• Eltek Valere AS assumes responsibility for the equipment in its original configuration only.

• Any intervention that alters the structure or operating cycle of the equipment must be carried out and authorised directly by Eltek Valere AS.

• Eltek Valere AS will not be held responsible for the consequences arising from the use of non-original spare parts.

• Eltek Valere AS reserves the right to make alterations and modifications to the documentation and to equipment without prior notice. Whenever typographical or other errors are found, the corrections will be included in new versions of the manual.


4. Regulations and Safety Warnings

Danger of injury due to electric shock

Always follow all safety instructions, in particular:

• all work on the equipment must be carried out by qualified personnel;

• only access internal components after having disconnected the device from its power supplies;

• always use specific protective devices for each type of activity;

• follow the instructions given in the manuals carefully;

Danger of injury due to device faults

Faults on the THEIA Central inverter may result in potentially dangerous situations arising.

• Do not use the device if it is visibly damaged.

• Carry out maintenance work regularly in order to detect possible faults.

Possible damage to the device

Before carrying out any work on the device, ensure that all precautions against electrostatic discharge that may damage the electronic part of the system have been taken.

Read the technical documentation

Before installing and using the equipment, ensure that you have read and understood all the instructions contained in this manual and in the remaining supporting technical documentation.


Nominal Data The THEIA Central inverter has an identification plate displaying its nominal operating data.

This plate is fixed to the inside of the door.

Figure 1 – Example THEIA Central characteristics plate

Check the technical characteristics

Before installing and turning on the inverter system, check that the technical characteristics are compatible with the photovoltaic field and AC supply network (or low-, or medium-voltage isolation transformer, if applicable).


5. General Description of Inverter

Basic Data on the Photovoltaic System Continual technical developments in industrialised countries and the fact that, very soon, even

the most remote locations will have access to modern technologies, have given energy a key role in all aspects of life worldwide, whether social or industrial. Consequently, the ability to supply and produce energy while controlling the emissions of pollutants and protecting the environment has become a priority.

Photovoltaic panels allow renewable energy such as solar energy to be converted into direct electrical energy (DC) by exploiting the photoelectric effect, namely the capacity that some semi-conductors have, suitably doped, to generate electricity if exposed to light radiation.

THEIA Central inverters enable the electrical distribution network to be supplied by using the energy produced from photovoltaic panels. The system may be equipped with a low-voltage transformer or connected a medium-voltage transformer for connection to the public distribution network by means of the appropriate interface devices.

Figure 2 – Basic photovoltaic system layout

A photovoltaic system comprises:

• a photovoltaic generator which transforms the energy irradiated by the sun into DC electrical energy (1);

• an inverter that converts the direct current into alternating current (2);

• a device to interface with the electrical distribution network;

• a bidirectional energy meter (3)

A photovoltaic generator is formed by either a string (panels connected in series) or a field (several strings in parallel) so as to minimise installation costs.

Thanks to the use of a bespoke Maximum Power Point Tracker (MPPT) system, the THEIA Central inverter is capable of extracting the maximum available power from the photovoltaic field, under all possible daylight exposure conditions.


Description of the System The THEIA Central inverter is made using IGBT technology, with a high switching frequency,

to enable low distortion of the current injected into the distribution network. The components used guarantee high reliability, very high efficiency and ease of maintenance.

Type The THEIA Central inverter is a three-phase inverter, with an isolated-neutral three-wire output

(TL version inverter – IT AC network) and a direct single input from a photovoltaic field. The inverter may also be supplied with an internal transformer, in which case the output is a four-wire output (TX version inverter – TT AC network). The inverter can be manually disconnected on the input side, by means of an appropriate device. Similarly, the output can be manually disconnected, by means of an appropriate device, protected by fuses. The connection of the inverter to the distribution network occurs automatically, by means of a three-phase contactor, called a generator device.

Operating Conditions During normal operation, the inverter behaves as a current generator and transfers active power

from the photovoltaic field to the distribution network maximising the amount of energy taken (by means of the MPPT algorithm) and the power factor, and minimising harmonic distortion. In this way, maximum efficiency is obtained from the photovoltaic field under any operating conditions.

If the internal or external interface protection is triggered, the inverter is automatically disconnected from the distribution network until the proper operating conditions are restored.

During periods when no energy is provided by the photovoltaic field, the inverter automatically goes into standby, keeping only one electronic control section on. As soon as the PV energy is back to a sufficient level, the inverter starts up again and connects to the distribution network automatically to resume production.

Operating Modes The inverter’s operating modes can be selected, from the front panel or the software remote interface, in the following modes:

• ON/OFF mode

• Constant Current mode

• MPPT (Maximum Power Point Tracking) mode

For each of these modes, the inverter automatically starts up and connects to the distribution network, with all the protective devices on. For a more detailed description of the above-mentioned modes, refer to the Chapter on How to Use the Front Panel.

System Start-up Mode

We strongly recommend that the Constant Current (Fixed Power) mode is used on initial start-up, in order to assess whether the photovoltaic field is working efficiently.


Controls and Operating Mechanisms The controls and operating mechanisms of the THEIA Central inverter are described below:

• DC input isolator switch

• AC output isolator switch

• “ON/OFF” inverter switch

• Emergency Power Off (EPO) button

• LCD control panel

Check the level of staff training

The THEIA Central inverter operating and control mechanisms must only be used by authorised personnel. We recommend that the level of training of staff responsible for use and maintenance of the system is checked.

Isolator Switches (DC input and AC output) The isolator switches on the THEIA Central inverter are used to isolate the power part of the device from the photovoltaic field and from the AC network.

Do not handle isolator switches under load

The system components undergo considerable stress if the DC and AC isolator switches are operated under load. We recommend that the isolator switches are operated when the inverter is off.

• Turn the inverter start selector switch to the “OFF” position.

• Handle the isolator switches.

Voltage present on terminals

The isolator switches do not completely isolate the inverter, inside which voltage from the photovoltaic field and the AC network is still present on the terminals. Before carrying out any maintenance work on the equipment:

• Completely isolate the device by means of the external switches;

• Wait at least 5 minutes for the condensers to discharge.

Inverter “ON/OFF” Selector Switch The “ON/OFF” selector switch enables the inverter to be switched on and off. When the selector is in the “ON” position, it enables the inverter to be switched on; if the irradiation conditions are enough to reach the minimum DC start voltage the system will come on automatically, otherwise it will remain on standby, consuming almost no power.


Figure 3 – Inverter Start Selector Switch

Emergency Power Off (EPO) push-button The Emergency Power Off push-button is used to disconnect the THEIA Central inverter immediately from the AC network and also switches off the inverter.

Once pressed, the button remains locked and can only be unlocked by rotating the knob, allowing the spring reset to return it to its original position.

Figure 4 – Emergency Power Off (EPO) Button

Only push the button in the event of a real emergency

The system components undergo considerable stress when the emergency stop button is pressed under load.

• Only use the emergency stop button in the event of a real emergency.

• Stop the device by means of the “ON/OFF” selector switch.

After unlocking, the inverter remains off and can only be switched on again by resetting the system from the front panel. The THEIA Central inverter also has two terminals (Eac1 & Eac2) to which a remote emergency stop contact is connected.

LCD Control Panel The THEIA Central inverter control panel is used to:

• Check the device’s operating parameters


• Check the alarms present

• Access the events log

• Display the operating statistics

• Change the operating parameters

The menu that enables parameters to be changed is protected by a password to prevent access by unauthorised personnel.


6. Front Panel The inverter’s front panel has a 2-line alphanumeric display plus 5 function keys and enables the status of the inverter to be fully monitored. The flow chart and status LEDs give an immediate idea of the device’s operation and, together with the LED bar, make it easy to determine its operating status.

Figure 5 – THEIA Central Inverter Front Panel


Flow Chart

Figure 6 – Flow Chart

LED 1

GREEN Input voltage within operating range

ORANGE Input voltage present but not within tolerance limits

RED Error on input voltage, excessive voltage, earth fault

OFF Input voltage not present or less than minimum operating threshold

LED 2 GREEN (Input) ICB switch closed and voltage within the operating range

LED 3 GREEN Inverter in operation

RED Inverter fault

OFF Inverter off with no faults

LED 4 GREEN (Output) OCB switch closed

LED 5 GREEN AC network frequency and voltage OK

RED AC network frequency and voltage fault

OFF AC network voltage below minimum threshold

Status LEDS

Figure 7 – Status LEDs

RUN

GREEN CPU in operation

TEST ORANGE Device in TEST mode

SERVICE ORANGE Technical Assistance required

STBY ORANGE System on stand-by

MPPT ON GREEN MPPT algorithm ON

EPO RED System stop by Emergency Power Off (EPO) button


LED Bar

Figure 8 – LED Bar

The LED bar gives an immediate indication of the percentage of power delivered by the machine, compared to the nominal power. Under “MPPT” operating conditions, the power delivered is a direct consequence of solar irradiation, namely the capacity of the photovoltaic field to produce energy. During “Manual Current” operation, the percentage of power may be altered manually; this mode is normally used when the device is first started and after a repair to the inverter or substantial changes to the photovoltaic field.

Function Keys The front panel of the THEIA Central inverter has 5 keys, whose functions are shown in the following table:

Key Assigned Functions

• Scrolls the menus up

• Increases the values by one unit

• Selects a value

• Scrolls the menus down

• Decreases the values by one unit

• Selects a value

• Selects a menu

• Confirms the selection of a value

• Confirms the changes

• Mutes the buzzer (activated as a result of

an alarm or fault)

• Returns to the previous menu

• Cancels a change

+ • Returns to the main screen


7. Managing the LCD Panel

Main Screen The main screen appears on the LCD panel when the inverter is operating normally (no alarms present). It shows the name of the device and the nominal power on the top line and three operating parameters on the bottom line which change cyclically every 5 seconds:

• Pnow: power fed into the network by THEIA Central inverter at the present moment

• Eday: energy produced by THEIA Central inverter during the current day

• Iout: current fed into the network by THEIA Central inverter at the present moment

Pressing one of the two or keys accesses navigation from which it is possible to access all the panel functions. You can return to the main screen by using the function keys as described in the preceding paragraph; this also happens automatically after 5 minutes if no alarms are active on the system.

THEIA TL 250 kWPnow 112 kW

THEIA TL 250 kW Eday 687 kWh

THEIA TL 250 kWIout 215 214 215 A

Main Menus

THEIA TL 250 kWOperating mode of the device

MODE

THEIA TL 250 kWCurrent and voltage measures of the device

MEASURES

THEIA TL 250 kWStatistics relating to the operating hours and energy produced

STATISTICS

THEIA TL 250 kWOperating status of the device, alarms and alarm log, if applicable

DIAGNOSTIC

5 sec

5 sec

5 sec


THEIA TL 250 kW Programming the THEIA Central inverter’s operating parameters

SETTINGS

THEIA TL 250 kW General information on the device

INFO

Modifying the Operating Mode The MODE menu is structured as follows:

Figure 9 – MEASURES Menu Structure

The MODE menu enables modifications to be made to the operating status of the device in order to carry out checks and tests.

Possible loss of efficiency of the device

Incorrect setting of the operating mode may have a negative impact on the efficiency of the device and cause severe stresses on the photovoltaic panels.

Three different operating modes can be selected:

• MPPT

• MANUAL CURRENT

• STAND-BY

The factory default setting is MPPT.

STAND-BY Mode In STAND-BY mode the inverter works in parallel with the network with minimum transfer of power from the photovoltaic field to the network itself. This operating mode can usefully be applied to achieve a momentary reduction in transfer of energy from the photovoltaic field to carry out checks or measurements.

MANUAL CURRENT Mode In MANUAL CURRENT mode it is possible to set, from the display, the quantity of energy to be transferred to the AC network, defined as a percentage of the rated power of the inverter.


System start-up mode

It is strongly recommended that Manual Current (Fixed Power) mode is used on initial start-up, in order to assess effective operation of the photovoltaic field.

If this mode is selected and confirmed, the menu automatically accesses the setting the current set-point procedure.

On the first line of the menu, the percentage value currently set is displayed, and on the second line the parameter can be modified.

CURRENT: 14 A 20 %The value on the second line is ready for modification. The increase or decrease is done in steps of 5%. 20 %

(5x)

CURRENT: 14 A 20 %The parameter is modified, and the modification is confirmed by pressing the (ENTER) key

45 %

CURRENT: 33 A 45 %The inverter is now in the operating conditions required by the operator

45 %

MPPT mode The THEIA Central inverter range uses an advanced MPPT (Maximum Power Point Tracking) algorithm, tested in the field, with a control system enabling monitoring of maximum power. The maximum power voltage point of the photovoltaic field can vary due to the changes in the irradiation and surface temperature of the photovoltaic panels.

The ‘take-off’ point of maximum power can thus vary considerably on the V-I characteristic of the photovoltaic field in a few seconds. The algorithm calculates the power supplied at determined intervals and moves the ‘take-off’ point of the photovoltaic field in order to transfer the maximum power available to the grid at that moment.


Figure 10 – Modification to ’take-off’ point of the photovoltaic field

Figure 11 – Response of MPPT algorithm to variations in field


Measures Display The MEASURES menu is structured as follows:

Figure 12 – MEASURES Menu Structure

Submenu Data Displayed Accuracy

PV Photovoltaic field voltage 1 V

Photovoltaic field current 1 A

GRID

Network voltage (1) (2) 1 V

Instantaneous current fed into the network (3) 1 V

Network frequency 1 A

INVERTER

Inverter voltage (1) (2) 1 V

Inverter current (3) 1 A

Inverter frequency 0.01 Hz

POWER Instantaneous power fed into the network 100 W (1) Voltage measurements are always taken between phase and neutral (2) The three voltages are displayed on one screen in the form ‘xxx yyy zzz V’ (3) The three line currents are displayed on one screen in the form ‘xxx yyy zzz A’


Statistics Display The STATISTICS MENU is structured as follows:

Figure 13 – STATISTICS menu structure

Sub-menu Data displayed

DAILY Hours of operation divided by day

Energy produced divided by day

MONTHLY Hours of operation divided by month

Energy produced divided by month

ANNUAL Hours of operation divided by year

Energy produced divided by year

TOTAL Hours of operation from the date of installation

Energy produced from the date of installation

The first statistic displayed is that relating to operating time.

DAILY STS : 9/0009 Display of operating time (final date stored in memory)

25-06-09 10 : 15 h

DAILY STS : 8/0009 Press the key to scroll the menu and move back to the previous event (in order of time)

24-06-09 12 : 22 h


Press the (ENTER) key to select the statistic relating to energy produced.

DAILY STS : x/YYYYdd-mm-yy Hours

DAILY STS : x/YYYYdd-mm-yy Energy

The first data item displayed is the last in order of time; a new data item automatically shifts the others by one position and deletes the oldest event.

The volume of data stored in memory is displayed on the first line (x/YYYY), which records the data item displayed at the time (position in the list) and the total number of data stored in memory respectively.

The maximum number of data that can be stored in memory for each statistic enables approximately four years of the device history (see Table below).

Statistic Format Max. N° of data items

Daily dd/mm/yy (e.g. 25-06-09) 1600 Monthly mm/yy (e.g. 06-09) 50 Annual yyyy (e.g. 2009) 5

Basic Diagnostics From the DIAGNOSTICS menu it is possible to display the current operating status of the device and access event histories, in line with the following structure.

Figure 14 – DIAGNOSTICS menu structure


ALARMS - STATES Alarms present and operating status

HISTORY Event histories

The LCD panel provides automatic access to the ALARMS – STATES menu whenever an alarm is detected; the acoustic, when enabled, is activated to indicate that a fault has occurred. Inhibition is selected by pressing button (BUZZER).


<ALARMS – STATES> Display of first alarm present (if there are no operating status alarms displays present)

Alarm/status nr. 1

<ALARMS – STATES> Press the key to scroll the menu and move on to the next alarm/status (in alphabetical order)

Last alarm/status

Automatic cancellation of alarms

If an alarm is activated and the conditions that initiated it are then eliminated, cancellation is automatic, as is re-starting of the system.

Display of Alarm Histories All events are recorded in the alarm history.

<DIAGNOSTIC> HISTORY

HISTORY xxx/YYYAlarm code Date/time

The first event displayed is the last in order of time; a new event automatically shifts the others by one position and deletes the oldest event.

The volume of events stored in memory is displayed on the first line (xxx/YYY), which records the data item displayed at that moment (position in the list) and the total number of data items stored in memory (maximum number is 200) respectively. An asterisk indicates automatic reset of the alarm.

HISTORY 001/015 Last event stored in memory (in order of time)

• E.g.: automatic reset of alarm ‘A3 – Insufficient PV voltage’ A3 * 26-06-09 06:55

HISTORY 002/015 Immediately preceding event

• E.g.: alarm ‘A3 – Insufficient PV voltage’ A3 25-06-09 19:45

HISTORY 015/015 First event stored in memory (in order of time)

A18 15-06-09 12:49


List of Alarms and States

ALARMS STATUS

A1 COMMON ALARM S1 PV FIELD OK A2 PV OVERVOLTAGE S2 GRID OK A3 PV UNDERVOLTAGE S3 INVERTER OK A4 ASYMMETRIC VDC S4 INV SYNCHRONIZED A5 EARTH PROTECTION S5 MPPT ON A6 FUSES BLOWN S6 SYSTEM STAND-BY A7 ERROR LOOP V S7 SYSTEM MANUAL A8 MAX CURR PROT S8 SYSTEM IN TEST A9 PLL FAIL S9 DERATING ON A10 MAXMIN VDC PROT A11 CPU FAULT A12 HIGH TEMPERATURE A13 PRIM FANS FAIL A14 OUTPUT DISCONN A15 FAULT K1 A16 OCB OPEN A17 INV OVERVOLTAGE A18 GRID OUT OF TOL A19 EPO PRESSED A20 EEPROM ERROR A21 FIRMWARE ERROR A22 INV BLOCKED A23 SUPPRES FAULT A24 EXT INTERF PROT A25 DESATURATION A26 OUT DC CURRENT A27 GRID MON FAULT A28 OUT FUSES BLOWN A29 INP FUSES BLOWN A30 INV OVERCURRENT

Display and alarm registration procedures

• On accessing the ALARM – STATES menu, the states are always displayed in ascending order.

• Alarms are displayed when they occur and can be inhibited with the buzzer.

• The alarms remain visible until present and are recorded automatically in the event history, with the date and time.


Resetting the EPO Alarm In case the local or remote emergency power off switch (EPO) is operated, the LCD display automatically shows a warning message. Through the display indications it is possible to reset the alarm and re-start the system.

EPO PRESSED

RESET EPO?

EPO PRESSED This window is shown in case the EPO switch has not been released

RELEASE EPO SWITCH

RESET EPO ? The value on the second line is ready for modification

NO

(1x)

RESET EPO ? The parameter is modified and the modification is confirmed by pressing the (ENTER) key

YES

THEIA TL 250 kW The system re-starts automatically

Pnow 0 kW


8. Programming of Parameters Some of the operating parameters of the THEIA Central inverter can be set from the SETTINGS menu, which is structured as follows:

Figure 15 – SETTINGS menu structure


Sub-menu Programmable data

CLOCK System date and time

MPPT Time interval for calculating the MPPT algorithm

Voltage step of MPPT algorithm

PV VOLTAGE START Setting the minimum voltage for inverter start-up

STAND-BY TIME Wait time for start-up of inverter

NIGHTLY POWER OFF Setting the night shutdown threshold

MODBUS MODBUS parameters (address of the device, Baud rate, etc.)

BUZZER Enabling / disabling acoustic alarm indication

LANGUAGE Setting the display language

INSTALLATION DATE Setting the device installation date

RESET Reset of certain blocking conditions (e.g. EPO)

RESET HISTORY Reset of event history

GRID TOLERANCE Setting the positive and negative grid voltage thresholds.

Password protected access

The SETTINGS menu is protected by two factory-set passwords to prevent access by unauthorized personnel, a USER password and a SERVICE password.

• It is advisable to minimise disclosure of the access passwords.

• Modifications to operating parameters by logging in with the SERVICE password (advanced settings) may be potentially hazardous to the device itself and for the photovoltaic field.


Setting the Date and Time The date and time can be set from the CLOCK menu.

<CLOCK> The individual digits are modified using the arrow keys ( / ) and confirmed with the (ENTER) key DD-MM-YY hh : mm

Setting the current date and time correctly

Correct setting of the date and time is a key requirement for recording event histories.

Setting MPPT parameters (Advanced setting) Some MPPT algorithm parameters are configurable by the operator based on the installation characteristics, in order to maximise performance.

MPPT Rate This parameter configures the time interval (in seconds) in which the MPPT algorithm calculates the power differentials.

The first line of the menu displays the value currently set, and in the second line the parameter can be modified.

MPPT RATE : 05.0 The individual figures can be changed using the arrow keys ( / ) and confirmed with the (ENTER) key 05.0

Possible instability of the system or loss of efficiency

• Low MPPR RATE values may generate errors in monitoring maximum power, and hence in the energy produced.

• High MMPT RATE values can result in loss of power transferred due to delays in monitoring under different conditions.

Voltage Step This represents variations in voltage (in Volts) set by the MPPT algorithm between the take-off points of the photovoltaic field, on which the calculation of power variation is based.

VOLTAGE STEP : 10 The individual figures are changed using the arrow keys ( / ) and are confirmed with the (ENTER) key 010


The MPPT parameters are set at factory defaults levels, but may be set within a clearly defined range, as shown in the Table below.

Parameter Default Range

MPPT RATE 5 s 1 …. 100 s

VOLTAGE STEP 10 V 1 …. 20 V

Setting Starting Voltage (Advanced Setting) The starting voltage represents the PV field’s minimum voltage level to which the inverter is allowed to start. It can also be defined as the tolerance threshold of the photovoltaic field when the voltage rises after a minimum voltage alarm (see figure).

Figure 16 – Inverter start-up conditions

PV V START: 650 The individual figures are changed using the arrow keys ( / ) and are confirmed with the (ENTER) key 650 V


PV V START 650 V 450.…. 750 V

Setting Stand-By Time (Advanced Setting) The stand-by time represents the interval of time between the return of the photovoltaic field voltage to tolerance values and start-up of the inverter, expressed in seconds. Likewise, this parameter has to be adjusted during installation, based on the capacity of the panels to produce current at a faster or slower rate on reinstatement of the minimum light conditions.


STAND-BY TIME : 180 The individual figures are changed using the arrow keys ( / ) and are confirmed with the (ENTER) key 180

During start-up of the system, as soon as the microprocessor control identifies that the voltage of the photovoltaic field is within tolerance values, the inverter assumes stand-by status for the time set and the LCD panel displays a warning box.

PV OK : 2 : 59 sPress ENTER to skip

The countdown process (stand-by) can be interrupted by pressing the key and then proceeding immediately with start-up of the inverter.


STAND-BY TIME 180 s 1 …. 900 s

Setting Nightly Power Off (Advanced Setting) The nightly power off threshold represents the minimum power, below which the inverter is turned off; the shutdown is delayed 3 minutes.

Such condition normally occurs before the sunset, when the solar radiation decreases constantly. It may also occur during particular darkness conditions (thunderstorms or heavy cloud covering); in such a case the inverter re-starts automatically when the optimal operating conditions are restored.

PERC OF POWER : 2.5% The individual figures are changed using the arrow keys ( / ) and are confirmed with the (ENTER) key 02.5


NIGHTLY POWER OFF 2,5 % 1 …. 10 %

Setting Modbus Parameters (Advanced Setting) The parameters relevant to the communication through RS485 support (Modbus protocol) can be set inside the MODBUS menu.

• Modbus address

• Transmission speed (Baud Rate)

• Stop bits and parity of the data packet

MODBUS ADDRESS: 202The individual figures are changed using the arrow keys ( / ) and are confirmed with the (ENTER) key 202



MODBUS ADDRESS 1 1 …. 247

BAUD RATE : 9600 The value is changed using the arrow keys ( / ) and is confirmed with the (ENTER) key

9600


BAUD RATE 9600 9600 19200

BIT : 2 PARITY NO The value is changed using the arrow keys ( / ) and is confirmed with the (ENTER) key

2 NO


STOP BIT AND PARITY 2 / NONE 2 / NONE 1 / ODD 1 / EVEN

Setting Grid Tolerance (Advanced setting) The grid tolerance (positive and negative thresholds) can be set by the operator according to the

grid characteristics.

Grid Positive Tolerance This parameter configures the grid voltage upper threshold. The first line of the menu displays the value currently set, and in the second line the parameter

can be modified.

GRID POS TOL : 10 % The individual figures can be changed using the arrow keys ( / ) and confirmed with the (ENTER) key 10

Grid Negative Tolerance This parameter configures the grid voltage lower threshold. The first line of the menu displays the value currently set, and in the second line the parameter

can be modified.

GRID NEG TOL : 10 % The individual figures can be changed using the arrow keys ( / ) and confirmed with the (ENTER) key 10


Other Parameters The table below shows the other parameters that can be programmed using the SETTINGS menu, together with the settable range of values.


BUZZER ENABLED ENABLED DISABLED

LANGUAGE ENGLISH

ITALIAN GERMAN FRENCH ENGLISH PORTUGUESE SPANISH

INSTALLATION DATE (ADVANCED setting)

00-00-00 01-01-2000 …. 31-12-2099

The procedure for changing the parameters is the same as for all others, using the arrow keys ( /

) to increment the figures and the key to confirm the selection.


Resetting the System The THEIA Central inverter is equipped with internal protection features which cut off the inverter, and consequently shut-off the current supply to the AC network. The system can be unlocked and a controlled restart of the inverter initialised by using the RESET menu.

START RESET ? The value on the second line is ready for modification

NO

(1x)

START RESET ? The parameter is modified and the modification is confirmed by pressing the (ENTER) key

YES

THEIA TL 250 kW The system implements the reset and returns to the main screen

Pnow 65 kW

The blocking conditions dictating a manual reset are as follows:

• Deployment of the de-saturation sensor of the inverter bridge (alarm A8)

• Blocking of inverter due to anomaly (alarm A22)

Deleting History Data (Advanced Setting) History data stored in the memory can be deleted using the SETTINGS menu.

Resetting the Alarm History Access the HISTORY RESET menu.

RESET HISTORY ? The value in the second line is ready for modification

NO

(1x)

RESET HISTORY ? The parameter is modified, and the modification is confirmed by pressing the (ENTER) key

YES

THEIA TL 250 kW The system implements the reset of the alarm history and returns to the main screen

Pnow 65 kW


9. System Information The INFO menu provides general information on the THEIA Central inverter, in line with the structure shown below.

Figure 17 – Structure of INFO menu

All of the data shown inside the various boxes are factory set using a dedicated interface software program and can only be modified by personnel authorized to do so by Eltek Valere.

The only parameters than can be modified are the MODBUS settings (see SETTINGS menu).



NAME Device name

POWER Rated output power

SERIAL NUMBER Serial number of device assigned by manufacturer

OEM SERIAL NUMBER Serial number assigned by OEM distributor where applicable

PARALLEL DEVICE Position of the inverter in operation in parallel (optional feature)

MODBUS MODBUS address of the device and communication parameters (Baud rate, word length, stop bit, parity)

SERVICE Company name

General information

FIRMWARE VERSION Versions of firmware installed on board the two system CPUs

INSTALLATION DATE Date of installation of the device, set via the SETTINGS menu

Information on Service The SERVICE menu is split into two sub-menus which provide important information and technical assistance for the THEIA Central inverter


COMPANY Name of company responsible for providing assistance on the device

GENERAL INFO General information relating to contact (Telephone N°, Fax N°, e-mail, etc.)

The information in both menus is displayed by a text string of maximum 60 characters which scroll in the second line of the display.

Reference can also be made to the addresses and contact numbers given in this manual.


10. Failures and Alarms As stated in preceding sections, the system is equipped with basic diagnostics enabling an immediate display of the operating conditions. In the event of an alarm, the inverter may disconnects momentarily from the AC network until the cause that generated the stop is resolved.

The LCD panel immediately displays the alarm screen and the acoustic indicator is activated (if enabled). Each box then displays the alphanumeric code of the alarm and a brief description of the alarm.

<ALARMS – STATES> The display shows the alarms in chronological order.

A3 PV UNDERVOLTAGE

(1x)

<ALARMS – STATES> By scrolling the menu, the other alarms present are displayed

A14 OUTPUT DISCONN

<ALARMS – STATES> After the final alarm, the system jumps to the operating status display

S2 GRID OK

Risk of injury due to electric shock

Before proceeding with any work on the THEIA Central inverter, be sure to comply with all safety instructions:

• Any work on the equipment must be carried out by qualified personnel;

• The internal components should only be accessed once the device has been disconnected from the power supply;

• Always use special protective equipment for all types of work;

• Follow the instructions given in the manuals carefully;

• In case of doubt or if a problem cannot be resolved, contact Eltek Valere immediately.


Definition of Operating States

Status S1 PV FIELD OK

Description The voltage of the photovoltaic field is within the operating range.

Operating state

The inverter is OK to start up; if the start-up selector switch is in the ‘ON’ position, the system initiates the start up procedure.

Status S2 GRID OK

Description The voltage and frequency of the AC network are within the operating range.

Operating state

The network device (output contactor) is OK to close and connect the inverter in parallel with the AC network.

Status S3 INVERTER OK

Description The voltage and frequency of the inverter are within the operating range.

Operating state

The inverter is ready to supply current to the network.

Status S4 INV SYNCHRONISED

Description The inverter is synchronised with the AC network..

Operating state

The synchronisation system is linked to the network frequency which the inverter attains as soon as it has started up.

Status S5 MPPT ON

Description The MPPT algorithm is activated.

Operating state

The inverter supplies current, looking for maximum transfer of power from the photovoltaic field, in accordance with the parameters set by the algorithm.

Status S6 SYSTEM STAND-BY

Description The inverter is in stand-by mode.

Operating state

The inverter is in parallel with the AC network with negligible transfer of power.

Status S7 SYSTEM MANUAL

Description The inverter is in manual control mode.

Operating state

The inverter is in parallel with the AC network. Control of the output current and hence transfer of power is handled manually via the LCD panel.


Status S8 SYSTEM IN TEST

Description The inverter is in TEST mode.

Operating state

The inverter is switched off pending operator instructions. To use this mode, suitable interface software is required, only issued to trained and qualified personnel to provide technical assistance.

Status S9 DERATING ON

Description The inverter is supplying power at a reduced rate.

Operating state

The inverter is operating in parallel with the AC network. If the temperature of the heat-sink rises above 75°C (value set using interface software) the control system starts up the fans and reduces the power supplied until the temperature stabilises at a lower value (set value –2°C). At this point the control system increases the output power (if the photovoltaic field permits this), checking the temperature at the same time. If the temperature remains below the set value, the MPPT algorithm is reactivated, otherwise the system changes back to “DERATING ON” status.


Troubleshooting

Alarm A1 COMMON ALARM

Description Cumulative alarm.

Possible causes

• At least one alarm is present.

Solutions 1. Check which alarms are present and implement the procedures stated.

Alarm A2 PV OVERVOLTAGE

Description The input voltage (photovoltaic field) measured by the system is higher than the maximum admissible threshold.

Possible causes

• Error in photovoltaic field design (maximum effective voltage too high).

• Possible measuring circuit fault.

Solutions 1. Check the effective value of the DC voltage.

• If the voltage falls outside the range check the design calculation data of the photovoltaic field.

2. Check the value of the DC voltage measured by the inverter.

3. Restart the device.

4. If the alarm persists, contact the Service Department.

Alarm A3 PV UNDERVOLTAGE

Description The input voltage (photovoltaic field) measured by the system is lower than the admissible minimum threshold.

Possible causes

• Solar radiation insufficient to guarantee the minimum voltage level.


Solutions 1. Check the effective value of the measured DC voltage.

• If the voltage falls outside the range wait until solar radiation increases.

2. Check the value of the DC voltage measured by the inverter.

3. Restart the device.

4. If the alarm persists contact the Service Department.

Alarm A4 ASYMMETRIC VDC

Description The voltage values measured on the DC capacitors (positive and negative in relation to centre point) are different.

Possible causes


• Possible anomaly on DC capacitors

Solutions 1. Restart the device.



Alarm A5 EARTH PROT

Description The system has detected an earth leakage. The indication comes from the external earth fault sensor, which has an alarm contact connected to terminals X10-1 / X10-2.

Possible causes

• The insulation resistance of the photovoltaic field is lower than the set limit value.

Solutions 1. Check the photovoltaic field for earth leakage.

2. If there is a loss of insulation, check strings for absence of load.

3. Check operation of the earth fault sensor.


Alarm A6 FUSES BLOWN

Description Failure of AC protection fuses.

Possible causes

• Output over-current.

Solutions 1. Check the fuses and the status of the melting indicator.

2. Replace any fuses that have failed.

3. Re-start the system.


Alarm A7 ERROR LOOP V

Description The control system is unable to minimise the voltage differential between the inverter and the AC network.

Possible causes

• Instability of the AC voltage.

• Failure of the control system.

Solutions 1. Check the stability of the AC network voltage



Alarm A8 MAX CURR PROT

Description The control system has detected an over-current at the inverter bridge input.

Possible causes

• Failure of the inverter bridge

• Temporary current peak.

Solutions 1. Re-start the system.


Alarm A9 PLL FAIL

Description Anomaly in the frequency control system. Internal fault.

Possible causes

• Control system fault.




Alarm A10 MAXMIN VDC PROT

Description Actuation of the safety sensor due to sudden variations in the DC input voltage.

Possible causes

• Fault in the photovoltaic field.

Solutions 1. Check the individual strings of the photovoltaic field.



Alarm A11 CPU FAULT

Description Microcontroller fault. Internal fault.

Possible causes

• Fault in microprocessor communications bus.

• Wrong software used.

Solutions 1. Check the presence of alarms A20 and A21 and implement corresponding procedures accordingly.



Alarm A12 HIGH TEMP

Description High temperature on heat sink of inverter bridge.

Possible causes

• Fault on heat sink cooling fans.

• Room or cooling air temperature too high.

Solutions 1. Check operation of the fans.

2. Clean the ventilation grilles and any air filters.

3. Check the air-conditioning system (where present).


Alarm A13 PRIM FANS FAIL

Description The fan monitoring card has detected a fault.

Possible causes

• Heat sink cooling fan fault.

Solutions 1. Check fan operation.

2. Replace any defective fans.


Alarm A14 OUTPUT DISCONN

Description The inverter is disconnected from the AC network.

Possible causes

• Output isolator switch open.

• Network device (output contactor) open.

Solutions 1. Check the status of the output isolator switch and the contactor.



Alarm A15 FAULT K1

Description Inconsistency between the operating status of the machine and the status of the output contactor.

Possible causes

• Fault on output contactor or auxiliary relay.

Solutions 1. Check operation of contactor K1 and the auxiliary relay.


Alarm A16 OCB OPEN

Description The output isolator is open.

Possible causes

• Output isolator open.

Solutions 1. Check the status of the output isolator.

2. Check operation of the auxiliary contact of the isolator.


Alarm A17 INV OVERVOLTAGE

Description The inverter output voltage is too high.

Possible causes

• Rapid variations due to the AC network.


Solutions 1. Check the stability of the AC network voltage.



Alarm A18 GRID OUT OF TOL

Description Voltage or frequency of the AC network outside the tolerance range.

Possible causes

• Instability or absence of the AC network.

Solutions 1. Check the connections to the AC network.

2. Check the stability of the AC network voltage.


Alarm A19 EPO PRESSED

Description The system is locked out due to actuation of the emergency stop button.

Possible causes

• Actuation of the emergency stop button (local or remote).

Solutions 1. Release the emergency stop and reset the alarm.



Alarm A20 EEPROM ERROR

Description The controller has registered an error in the parameters stored in memory in E2PROM.

Possible causes

• Wrong parameters set during programming.

Solutions 1. Contact the Service Department.

Alarm A21 FIRMWARE ERROR

Description The controller has detected incompatibilities in the control software.

Possible causes

• Software update not implemented correctly.

Solutions 1. Contact the Service Department.

Alarm A22 INV BLOCKED

Description The inverter is blocked due to an operating fault.

Possible causes

• Various

Solutions 1. Reset the alarm.


Alarm A23 SUPPRES FAULT

Description Activation of the surge arresters.

Possible causes

• Atmospheric discharge.

Solutions 1. Check the surge arrester and replace if necessary.

2. Check and replace the fuse(s) of the surge arresters where necessary


Alarm A24 EXT INTERF PROT

Description The system is blocked following actuation of the external interface protection, which has indicator contacts connected to terminals X10-1 / X10-2.

Possible causes

• Instability or absence of the AC network.

Solutions 1. Check the status of the external interface protection.

2. Check the stability of the AC network voltage.



Alarm A25 DESATURATION

Description The system is blocked due to actuation of the de-saturation sensor of the IGBT drivers.

Possible causes

• Inverter bridge fault.



Alarm A26 OUT DC CURRENT

Description The control system has detected a continuous component in the output current.

Possible causes




Alarm A27 GRID MON FAULT

Description AC mains monitoring system fault (only if the external interface protection is installed).

Possible causes

• External monitoring device fault.


Solutions 1. Check the external monitoring device.

2. Verify the acquisition of the measures by the control logic.



Alarm A28 OUT FUSES BLOWN (only for 20kW, 30kW, and 50kW)

Description Failure of AC protection fuses.

Possible causes

• Output over-current.






Alarm A29 INP FUSES BLOWN (only for 20kW, 30kW, and 50kW)

Description Failure of DC protection fuses.

Possible causes

• Input over-current.





Alarm A30 INV OVERCURRENT

Description Inverter output overcurrent.

Possible causes





11. Maintenance Some parts of the THEIA Central inverter require scheduled preventive maintenance to guarantee the efficiency, safety and operational life of the converter. Maintenance activities also include checking and, if necessary, preventive replacement of components most subject to wear and ageing during operation.

Danger of injury due to electrical shock

• Check that the device is switched off and disconnected from the DC and AC power sources.

• Should it be necessary to perform checks while the equipment is live, take the greatest care possible and use appropriate protective equipment.

Use qualified personnel only

Failure to perform the maintenance programme or carrying out of the programme by unqualified personnel seriously compromises the reliability and safety of the equipment. It is recommended that you use only qualified personnel authorised by Eltek Valere for all routine and special maintenance operations.

Maintenance Programme The following table shows the maintenance programme, including the recommended intervals for each operation. For particularly dirty environments, an increase in the frequency of checks is recommended.

Description of operation Recommended interval

Cleaning the ventilation grills and air filters 6 months

Cleaning the control and power electronics 12 months

Checking power cable tightness 12 months

Visual check of magnetic parts 12 months

Checking ventilator operation 12 months

Checking the control devices (DC and AC isolators) 12 months

Checking the protective fuses 12 months

Checking the generator device operation 12 months

Checking the surge arresters 12 months

Checking the mechanical parts of the cabinet 12 months


Test software

It is only possible to perform a reliable inspection and to check that the system is working at full efficiency by using a software programme that is the exclusive property of Eltek Valere. This programme may be used by authorised, qualified Eltek Valere personnel only. It is not possible to fully guarantee the effectiveness of operations carried out unless they are checked using this tool.

Cleaning Ventilation Grills And Air Filters The THEIA Central inverter is designed to be mounted against walls. The ventilation grills are therefore located on the front (air inlet) and top (air outlet) of the cabinet only. The diagram below shows one type of mechanical cabinet.

Figure 18 – THEIA Central inverter ventilation grills

If only dust is present, use a brush.

• A vacuum cleaner or compressed air may also be used. In the latter case, take care not to direct the air jet into the cabinet.


Cleaning Control and Power Electronics The control electronics are located on the inner panel of the door. The entire power section is fitted onto the front of the inner plate of the assembly.

1. Use a brush to remove any dust deposits from the circuit board.

2. Compressed air may be used to remove dirt from the heat sink and from the power components.

Checking Power Cable Terminals 1. Check the terminals of all power cables and, if necessary, tighten them correctly.

2. Check for the presence of elements which may have a corrosive or damaging effect (clamps, terminals, etc.) and replace as necessary.

Visual Check of Magnetic Parts 1. Check the terminals of all associated cables and, if necessary, tighten them correctly.

2. Run a visual check on the state of the connections.

3. Look out for any variations in colour of the insulation around the magnetic parts.

4. If any anomalies are detected, arrange further electrical checks.

Checking Fan Operation The fans installed in the THEIA Central inverter are automatically monitored while the inverter is in operation; otherwise, they are not able to ensure maximum reliability during use.

In the absence of any failure signals from the inverter's control panel, check the component noise level only.

• Fans emitting occasional metallic noises must be replaced as soon as possible as this indicates the deterioration of the rotating parts.


Checking Control Devices (DC and AC Isolators Switches)

In general the control devices do not require maintenance, only a check on the state of the power connections.

Do not handle isolator switches under load

The system components undergo considerable stress if the DC and AC isolator switches are handled when under load. We recommend that the isolator switches are handled only when the inverter is switched off.

• Turn the inverter start dial to the ‘OFF’ position.

• Operate the isolators.

1. Look out for any variations in colour of the power contacts and for signs of corrosion.

2. Clean and, if necessary, replace any damaged connections.

Checking Protective Fuses In the event that a fuse interrupts the circuit, this is indicated on the front panel of the THEIA Central inverter by the relevant warning signal on the device.

Should a failure be indicated, replace the fuse.

In the absence of any failure, run a visual check on the state of the component.

1. Check for of any signs of corrosion or mechanical deterioration.

2. Replace any components showing signs of deterioration on the power contacts.

Checking Generator Device The generator consists of a contactor located at the inverter output, upstream of the manual output isolator switch.

The contactor may only be checked using the appropriate command and check software.

• In the event of sub-standard operation, replace the component.

Checking Surge Arresters In the event that the surge arresters activate, this is indicated on the front panel of the THEIA Central inverter by the relevant warning signal on the device.

Proceed with a visual check of the devices, checking the status window indicator on the device itself.


Figure 19 – Surge arresters

1. Check the colour displayed inside the window indicator.

2. If the indicator is red or partially red ("in reserve" function in AC surge arrestors) replace the component.

3. If the operation of the surge arrestor is not indicated on the front of the assembly, replace the indicator contact fitted on the surge arrestors.

The "in reserve" function

Under the "in reserve" function, the indicator contact moves to the failure position, immediately informing the operator that there is a problem. Protection is guaranteed, however, thanks to the 2 stage intervention system.

Checking the Mechanical Parts of the Cabinet The mechanical parts of the cabinet must be inspected to prevent deterioration due to environmental factors.

Locks and hinges

1. Check that the lock fastens correctly by opening and closing the door.

• If it is difficult to open the lock, check for corroded or damaged parts in the lock and clean or fully replace.

2. Check for any signs of rust or deterioration of the hinges and ensure that the door moves easily.

• If any damage is detected, replace the relevant part.

• If the door is stiff, apply a suitable lubricant to all moving parts.

Trim

1. Check the state of the trim inside the door for damage.

• If any damage is detected outside the area in contact with the door frame, the tightness of the door may still be considered good.

• If the damage is located on contact areas, replace the trim.



www.eltekvalere.com

Headquarters:Eltek Valere

Gråterudv. 8, Pb 2340 Strømsø, 3003 Drammen, NorwayPhone: +47 32 20 32 00 Fax: +47 32 20 32 10

Documents

User Guide for THEIA Central Inverters