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GE Digital Energy 

Power Quality 

 
 
 
 

 

 
 
 
 
 

Operating Manual 

Uninterruptible Power supply 

Digital Energy™ 

LP 33U Series 

50 & 60 kVA 

208 VAC UL   /   Series 1

 

 
 
 
 
 
 

GE Consumer & Industrial SA 

General Electric Company 
CH – 6595 Riazzino (Locarno) 
Switzerland 
T +41 (0)91 / 850 51 51 
F +41 (0)91 / 850 51 44 

 

www.gedigitalenergy.com

 

 
 
 
 

 

 

GE imagination at work 

Summary of Contents for LP 33U Series

Page 1: ...rruptible Power supply Digital Energy LP 33U Series 50 60 kVA 208 VAC UL Series 1 GE Consumer Industrial SA General Electric Company CH 6595 Riazzino Locarno Switzerland T 41 0 91 850 51 51 F 41 0 91 850 51 44 www gedigitalenergy com GE imagination at work ...

Page 2: ...A All rights reserved The information contained in this publication is intended solely for the purposes indicated The present publication and any other documentation supplied with the UPS system is not to be reproduced either in part or in its entirety without the prior written consent of GE The illustrations and plans describing the equipment are intended as general reference only and are not nec...

Page 3: ...the necessary information about the installation of the UPS Thank you for choosing GE START UP AND COMMISSIONING A GE Global Services Field Engineer must perform start up and commissioning of the UPS Please Contact GE Global Services at least two weeks prior to schedule start up and commissioning at 1 800 637 1738 or by E mail at pqservices ge com Sold in the North America by Your service contact ...

Page 4: ...t that needs to be installed by a licensed and knowledgeable contractor We recommend that this manual be kept next to the UPS for future references If any problems are encountered with the procedures contained in this manual please contact your Service Center before you proceed This document shall not be copied or reproduced without the permission of GE Some of the information contained in this ma...

Page 5: ...INGLE LP 33U Series 41 7 1 1 Start up of the LP 33U Series 41 7 1 2 UPS shutdown with load transfer on manual bypass Q2 45 7 1 3 From Manual Bypass Q2 to normal function VFI 47 7 1 4 Complete UPS shutdown 48 7 1 5 Restore to normal operation after Total Off 49 7 1 6 Restore to normal operation after EPO Emergency Power Off 50 7 2 PROCEDURES FOR LP 33U Series PARALLEL SYSTEM 51 7 2 1 LP 33U Series ...

Page 6: ...ed by qualified service personnel only The KNOWLEDGE and the FULLY compliance of the safety instructions and the warning contained in this manual are THE ONLY CONDITION to avoid any dangerous situations during installation operation maintenance work and to preserve the maximum reliability of the UPS system NOTE LP 33U Series 50 60 kVA is a FCC Class A UPS Product While every care has been taken to...

Page 7: ...ity Dangerous voltages may be present during battery operation The battery must be disconnected during maintenance or service work This UPS contains potentially hazardous voltages Be aware that the inverter can restart automatically after the utility voltage is restored STORAGE Store the UPS in a dry location storage temperature must be within 13 F 25 C to 131 F 55 C If the unit is stored for a pe...

Page 8: ... following symbols are defined WARNING if instruction is not followed injury or serious equipment damage may occur CAUTION internal parts have dangerous voltage present Risk of electric shock PE Earth GND Ground PROTECTIVE GROUNDING TERMINAL A terminal which must be connected to earth ground prior to making any other connection to the equipment A terminal to which or from which an alternating sine...

Page 9: ... Operating Manual LP 33U Series 30 40 kVA 2 LAYOUT 2 1 LAYOUT LP 33U Series 50 60 kVA Fig 2 1 1 General view UPS only Fig 2 1 2 General view UPS only with front door open Fig 2 1 4 Control panel Fig 2 1 3 General view UPS with Battery Cabinet Fig 2 1 5 Q1 Q2 switches ...

Page 10: ...al LP 33U Series 30 40 kVA Fig 2 1 6 General view with open door UPS with Battery Cabinet BC Battery cabinet CI Customer Interface Board optional FTM3 Battery Breaker Q1 UPS output switch Q2 Manual bypass switch RC Relay card SNMP Advanced SNMP Card optional RS232 Serial port RS232 ...

Page 11: ...imum energy saving The main typical performances of the LP 33U Series system are the following VFI Voltage Frequency Independent double conversion technology to provide an excellent quality power supply Input power factor 0 98 Input current THD 10 Automatic bypass and manual bypass to improve reliability and maintenance Microprocessor controlled supervision Dual AC inputs optional ECO Mode operati...

Page 12: ...ly independent from the AC input voltage Automatic Bypass The automatic bypass consists of a static semiconductor switch SSR Static Switch Relay used to provide an uninterrupted transfer of the load from inverter to mains when operating in VFI Mode If chosen the ECO Mode the SSM transfer the load from mains to inverter in case the utility fails Back Feed Protection All LP 33U Series UPS s are equi...

Page 13: ...telligent Energy Management When the ECO Mode is selected and the utility power is available the load is normally powered through the automatic bypass When the utility voltage is detected out of the prescribed tolerances the load is automatically transferred to the inverter When the utility recovers the load returns to the automatic bypass after a variable time defined by the control unit Fig 4 2 ...

Page 14: ...s operating It is excluded only if the unit is separated from the common bus by opening its output switch Q1 Utility recovery operation As soon as the utility recovers the rectifier starts up automatically supplying the inverter and the battery charger recharges the battery In case the inverter has been shut down following a complete discharge of the battery when the utility recovers the system st...

Page 15: ...applied load Fig 4 2 6 Energy flow during utility failure operation In the event of an extended utility failure before the battery is fully discharged the alarm stop operation warns the user that the UPS will start the shutdown procedures when the indicated time expired normally 3 minutes In case of parallel system With parallel system for power capacity With the bypass utility power available as ...

Page 16: ...nits connected on the output bars Should one of the parallel units trip off line the remaining n 1 units will share the load maintaining the applications protected by inverter until the normal situation restores Load sharing between parallel units The control bus exchanging the data between the microprocessors of the paralleled units provide for a constant proportional load sharing in every load c...

Page 17: ...Pay attention to the following recommendations The units delivered for this functioning mode needs a special parameters setting so they must be prepared in advance before the installation The installation must be performed only with the UPS system completely shut down The AC Rectifiers input power 5 must be the same with clockwise phase rotation for each unit Each Rectifier must be set for the sam...

Page 18: ...plier who provided the system Stamp of your Dealer or local responsible of the Technical Assistance see page 3 Fig 4 5 1 Identification label The requested data permitting to identify your UPS are marked on the identification label fixed on the front of the cabinet behind the lower front door For fast and efficient Technical Support solutions please mention the data marked on the identification la...

Page 19: ...respecting eco design rules It does not contain CFCs chlorofluorocarbons or HCFCs hydrochlorofluorocarbons GE in compliance with environment protection recommends to the User that the UPS equipment at the end of its service life must be recovered conforming to the local applicable regulations WARNING Leads contained in the batteries is a dangerous substance for the environment therefore it must be...

Page 20: ...the UPS front top acts as the UPS user interface and comprises of the following elements Back lit Graphic Display LCD with the following characteristics Multilanguage communication interface English German Italian Spanish French Finnish Polish Portuguese Czech Slovakian Chinese Swedish Russian and Dutch Synoptic diagram indicating UPS status Command keys and parameters setting UPS status control L...

Page 21: ...he Load It is possible to activate the command Total Off using the following screen COMMANDS REQUEST TOTAL OFF See Section 6 5 Attention TOTAL Off cannot disconnect the UPS from the Load with Q2 closed Home Commands COMMANDS RESET TOTAL OFF REQUEST TOTAL OFF To reset Total Off Restore the command Total Off by entering the screen COMMANDS RESET TOTAL OFF V For Parallel System if Total Off is presse...

Page 22: ...s not protected by UPS or in case Q1 is open LED Operation green color When lit indicates that the UPS is functioning correctly and the load is system protected Load supplied either from inverter or from Automatic Bypass in case of ECO Mode functionality When blinking indicates that a regular maintenance service is needed SERVICE REQUIRED May be reset by a service technician only See Section 9 Mai...

Page 23: ...ies 30 40 kVA 5 3 SWITCHES Q1 UPS output switch Q2 Manual bypass switch NOTE Do not switch ON Q1 and Q2 while Inverter is ON Fig 5 3 1 Q1 and Q2 switches NOTE Mains failure of long duration or low Battery voltage will cause the automatic shutdown of the UPS thus preventing damage to the Battery ...

Page 24: ...tomize some UPS functions to specific requirements and to view UPS identification data See Section 6 4 CMDS COMMANDS Allows the user to execute UPS operation commands See Section 6 5 The LCD screen after 5 minutes of inactivity shuts down the backlight To reactivate it it is sufficient to press any keys If the keypad remains inactive for 5 minutes or longer during the viewing of a screen such as M...

Page 25: ...tatus at 25 LED A Indicates a load level between 26 and 50 LED A B Indicate a load level between 51 and 75 LED A B C Indicate a load level between 76 and 100 LED A B C D Indicate a load level between 101 and 124 LED D blinking Indicates a load level 125 Fig 6 1 2 LEDs on synoptic diagram LEDs on synoptic diagram LED 1 Utility rectifier OK LED 2 Utility bypass OK LED 3 Rectifier ON LED 4 Dischargin...

Page 26: ...he battery charge level Autonomy The estimated backup time with the present load Charger mode The functionality of SBM Superior Battery Management can help to reduce the battery recharging time and improve the lifetime of the battery Beside the indication of the battery voltage on the display a letter shows according to the table below the operational status of SBM Abbreviation Status of charger C...

Page 27: ...RAL for each phase A The output current as RMS values RPA value for each UPS The output load as percentage RPA value for each UPS The source of the power supplied to the load Home Meter COUNTERS Bypass utility failure 53 Rectifier utility failure 35 Overloads 15 InvOperTime h 2135 UPSOperTime h 3125 Statistics screen The total number of minor utility faults bypass utility out of tolerance faults T...

Page 28: ...ushing the key for more than 3 seconds The events displayed are the standard GE events as described in the Section 6 3 1 EVENTS Alarms and Messages Home Alarm ALARM LEVEL 1 USER LEVEL 2 SERVICE V Alarms screen LEVEL 1 USER Chronologically view 2 events per screenshot LEVEL 2 SERVICE Chronologically view 5 events per screenshot with service related info Home Alarm User NR 255 06 05 2008 15 37 25 C ...

Page 29: ...LURE K4 not closed despite a closing command being done The rectifier is switched OFF 4103 K4 OPENING FAILURE K4 not open despite an opening command being done The rectifier is switched OFF 4110 RECTIFIER UTILITY OUT OF TOLERANCE Rectifier input utility has been detected out of tolerance voltage frequency or phase 4115 LOW BATTERY VOLTAGE The battery has been discharged and reached stop operation ...

Page 30: ...CTIFIER CANNOT BE TURNED ON The rectifier cannot be turned on because the DC link voltage has not reached the requested value 4404 K6 CLOSING FAILURE K6 not closed despite a closing command being done Signaled by auxiliary contact The load cannot be supplied by electronic bypass 4405 K6 OPENING FAILURE K6 not open despite an opening command being done Signaled by auxiliary contact 4410 BYPASS UTIL...

Page 31: ... would result below stop operation time default 3 minutes 4700 DC LOW Battery voltage is at the lowest limit Shutdown of inverter until the battery voltage reaches the value in respective parameter 4900 LOAD LOCKED ON INVERTER The load is locked on Inverter following 3 load transfers within 30 seconds After time out of the value in respective parameter default 30 seconds bypass will be free 4955 O...

Page 32: ...et ON signaling Operating mode dependent on setting of respective parameters 4164 GENERATOR OFF Customer Interface X1 11 22 received a Gen set OFF signaling Function bypass enabled dependent on setting of respective parameter 4302 INVERTER CANNOT BE TURNED ON Inverter cannot be switched on because one of the following conditions are still present Over temperature Low battery voltage Inverter fuses...

Page 33: ...ity bypass out of tolerance alarm 4410 or setting respective parameters 4583 COMMAND TO SYNCHRONIZE Command to synchronize with utility has been done for utility BP OK 4410 or setting respective parameters 4600 COMMAND UPS ON The ECO Mode function has been disabled or the programmed time is expired The UPS returns to VFI mode supplying the load normally by inverter 4601 COMMAND UPS STANDBY The fun...

Page 34: ..._ __ __ __ Series No UPS rating kVA Customer Place Date Sent by 1 Record the exact UPS status on the panel when the failure appeared 2 On the LCD panel enter the Alarms Mode and record the alarms messages in the list below indicating at least 5 events before the failure time Remark exact data and time are very important Event No Event Code UPS Status Date Time h m s 255 LED 1 ON OFF 254 LED 2 ON O...

Page 35: ...to set or modify the parameters ESC Allows to exit a selected screen without making any modification U Scrolls backward to the previous line V Scrolls forward to the next line Allows to access a value to be set or modified Select on the same line the following value or letter to set or modify Set or modify the selected value Save the set or modified value and return to the selected screen It is po...

Page 36: ...the remote control through modem calls by using this parameter For modem connection the default setting is for serial port J27 or J3 on Customer Interface option Init This parameter presents the modem initialization string It can be 40 characters long When editing this parameter the UPS considers that a blank character terminates the string If no blank character is found then all 40 characters are...

Page 37: ...ctive The activation deactivation of ECO Mode is indicated each time in the event list In order to check the inverter function at least 1 minute of VFI mode must be programmed during the week the Y N parameter is automatically disabled if this condition is not satisfied In case this minimum time in VFI mode is not respected the ECO Mode will be disabled If the value is N the UPS is normally operat...

Page 38: ... 3 ECO Mode during the night and week end If the ECO Mode must be enabled all nights d3 Monday to d7 Friday between 18 00 in the evening and 06 00 of the following morning and during all Saturday d1 and Sunday d2 the corresponding parameters are Weekday d1 Saturday d2 Sunday d3 Monday d4 Tuesday d5 Wednesday d6 Thursday d7 Friday ECO Mode START 00 00 00 00 18 00 18 00 18 00 18 00 18 00 ECO Mode ST...

Page 39: ... Mode STOP time of weekday d3 Monday has no effect as it is followed by the ECO Mode STOP time of weekday d4 Tuesday It can be without change of meaning any time between 18 00 and 23 59 Similarly the ECO Mode is active from 18 00 of weekday d4 Tuesday until 06 00 of weekday d5 Wednesday The ECO Mode START time of weekday d5 Wednesday has no effect as it is preceded by the ECO Mode START time of we...

Page 40: ...R ON INVERTER OFF BOOSTER ON Service V Commands screen 1 LAMP TEST Signaling LEDs test and buzzer test all LED should be lit and blinking and the acoustical alarm should be activated INVERTER ON Command to switch the inverter INVERTER OFF Command to shutdown the inverter BOOSTER ON Service Service only allowed Home Commands COMMANDS RESET TOTAL OFF REQUEST TOTAL OFF V Commands screen 2 RESET TOTAL...

Page 41: ...ses that the load is not yet supplied by the UPS system NOTE The UPS can be started up using the battery supply in case the input utility should be unavailable To avoid an incidental battery discharge it is recommended to proceed to the UPS start up having the input utility available Open the front door and make sure that All the connections to the input output terminals of the UPS have been made ...

Page 42: ...ns Without such configuration it is not possible to continue with the commissioning procedure WARNING The setup of the UPS configuration parameters must be done only by QUALIFIED AND TRAINED PERSONNEL The setup of mistaken values could compromise the integrity and reliability of the UPS In this mode the keys perform the following functions Confirm the selection made and select the next parameter E...

Page 43: ... of cells Autonomy times for lead acid batteries VRLA 2 x 72 cells Autonomy at full load at PF 0 8 U floating 164 Vdc 2 27 Vdc cell Battery with expected trickle life 5 years UPS Model 2 x 33Ah 48 blocks 4 x 33Ah 96 blocks 2 x 50Ah 48 blocks 3 x 50Ah 72 blocks 4 x 50Ah 96 blocks LP 33 Series 50 kVA 9 24 16 29 36 LP 33 Series 60 kVA 8 18 13 23 33 Autonomy time for battery supplied by GE UPS manufac...

Page 44: ...later the load will be transferred on inverter LED Alarm turn Off and the LED Operation must be lit The synoptic diagram must display the status LOAD SUPPLIED BY INVERTER 5 Load supply Your LP 33U Series UPS is now running in VFI mode supplying power to the output Insert the loads one by one to the output of the UPS Check the output current value of L1 L2 and L3 and check for correct load balance ...

Page 45: ... O key and hold until the LED inverter 7 turns OFF Load is transferred to utility by automatic bypass LED Alarm is lit and the LED Operation is Off The synoptic diagram must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 2 Close the manual bypass switch Q2 Pos I Load is now supplied parallel through automatic bypass and manual bypass Q2 The synoptic diagram must display the status LOAD SUPPL...

Page 46: ...ds The acoustical alarm is activated press MUTE key from Home screen to reset it 7 Disconnect the inverter by pressing Inverter OFF O key and hold until the LED inverter 7 turns OFF The load is now powered directly by utility through the MANUAL BYPASS Q2 END OF PROCEDURE WARNING If the above procedure is not completely performed it could cause serious damages to the UPS In case the procedure descr...

Page 47: ...d manual bypass Q2 The synoptic diagram must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS AND MANUAL BYPASS Q2 Home Commands COMMANDS RESET TOTAL OFF REQUEST TOTAL OFF 3 Only in case it has been previously activated restore the command Total Off by entering the screen COMMANDS RESET TOTAL OFF V Home Meter BOOSTER f 60 0 Hz L1 120 V L2 120 V L3 120 V Vp 215 V Vn 215 V 4 Open the manual bypa...

Page 48: ...below 7 Vac about 30 seconds The acoustical alarm is activated press MUTE key from Home screen to reset it Home Meter BOOSTER f 60 0 Hz L1 120 V L2 120 V L3 120 V Vp 5 V Vn 5 V Before proceeding to step 5 check on the display panel that the DC link voltage both polarities Vp and Vn has reached the max voltage of 5 Vdc about 30 seconds 5 Disconnect the inverter by pressing Inverter OFF O key and ho...

Page 49: ...witch shutdown Home Commands COMMANDS RESET TOTAL OFF REQUEST TOTAL OFF 1 Reset Total Off Restore the command Total Off by entering the screen COMMANDS RESET TOTAL OFF LED Alarm is lit V The load is supplied by the utility through the automatic bypass The booster starts automatically The synoptic diagram must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 2 Insert the inverter by pressing In...

Page 50: ...open Booster Inverter and Static Switch shutdown 1 Reset the EPO key Press MUTE key to reset Alarm and Acoustical alarm LED Alarm remains lit 2 Reset the UPS by pressing Inverter OFF O key The load is supplied by the utility through the automatic bypass The booster starts automatically The synoptic diagram must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 3 Insert the inverter by pressing ...

Page 51: ...s not yet supplied by the UPS Parallel System NOTE The UPS Parallel System can be started up using the battery supply in case the input utility should be unavailable To avoid an incidental battery discharge it is recommended to proceed to the UPS Parallel System start up having the input utility available Open the front door on all UPS units and make sure that All the connections to the input outp...

Page 52: ...ed in the following screens Without such configuration it is not possible to continue with the commissioning procedure WARNING The setup of the UPS configuration parameters must be done only by QUALIFIED AND TRAINED PERSONNEL The setup of mistaken values could compromise the integrity and reliability of the UPS In this mode the keys perform the following functions Confirm the selection made and se...

Page 53: ... of cells Autonomy times for lead acid batteries VRLA 2 x 72 cells Autonomy at full load at PF 0 8 U floating 164 Vdc 2 27 Vdc cell Battery with expected trickle life 5 years UPS Model 2 x 33Ah 48 blocks 4 x 33Ah 96 blocks 2 x 50Ah 48 blocks 3 x 50Ah 72 blocks 4 x 50Ah 96 blocks LP 33 Series 50 kVA 9 24 16 29 36 LP 33 Series 60 kVA 8 18 13 23 33 Autonomy time for battery supplied by GE UPS manufac...

Page 54: ...t be is lit The synoptic diagram on first UPS unit must display the status LOAD SUPPLIED BY INVERTER 5 Insert the inverter by pressing Inverter ON I key on all other UPS units Do not start the next inverter until the sequence of the previous one end As soon as the output power of the inverters is sufficient to supply the load the output of the units with running inverter will transfer to inverter ...

Page 55: ...ut will be supplied by the utility through all automatic bypass LEDs Alarm are lit and the LEDs Operation are Off The synoptic diagram on all UPS units must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 2 Close the manual bypass switch Q2 Pos I on all UPS units Load is now supplied from utility in parallel from automatic bypass and manual bypass Q2 of all UPS units The synoptic diagram on a...

Page 56: ...key from Home screen to reset it 7 Disconnect the inverter on all UPS units by pressing Inverter OFF O key and hold until the LED Inverter 7 turns OFF The load is now powered directly by utility through all MANUAL BYPASS Q2 The synoptic diagram on all UPS units must display the status LOAD SUPPLIED BY MANUAL BYPASS Q2 END OF PROCEDURE WARNING If the above procedure is not completely performed it c...

Page 57: ...any one of the units by entering the screen COMMANDS RESET TOTAL OFF V Home Meter BOOSTER f 60 0 Hz L1 120 V L2 120 V L3 120 V Vp 215 V Vn 215 V 3 Open the manual bypass switch Q2 Pos 0 on all UPS units The load is supplied by the utility through the automatic bypass Verify on all UPS units selecting the screen METERING BOOSTER Vp and Vn that the booster voltage has reached about 215 Vdc 4 Insert ...

Page 58: ...tch OFF battery breaker only from battery cabinet belongs to this unit 5 In order to discharge the DC link capacitors insert the inverter by pressing Inverter ON I key only on this unit Home Meter INVERTER f 60 0 Hz L1 7 V L2 7 V L3 7 V T OK SYNCHRONIZED Remark Command INVERTER ON will be enabled only when the inverter voltage of each phase decreases below 7 Vac about 30 seconds Home Meter BOOSTER...

Page 59: ...ltage from the input distribution both rectifier and bypass if separated on this UPS unit Overall test results Test1 OK Test7 OK Test2 OK Test8 OK Test3 OK Test9 OK Test4 OK Test10 OK Test5 OK Test11 OK Test6 OK The UPS performs a SELFTEST A successful termination of the tests will be indicated with Overall test results OK Commissioning cannot be continued should one or more tests result to be neg...

Page 60: ...er voltage of each phase decreases below 7 Vac about 30 seconds Home Meter BOOSTER f 60 0 Hz L1 120 V L2 120 V L3 120 V Vp 5 V Vn 5 V Before proceeding to step 5 check on the display panel that the DC link voltage both polarities Vp and Vn has reached the max voltage of 5 Vdc about 30 seconds The acoustical alarm is activated press MUTE key from Home screen to reset it 5 Disconnect the inverter on...

Page 61: ...y the utility through the automatic bypass The booster starts automatically The synoptic diagram on all UPS units must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 2 Insert the inverter by pressing Inverter ON I key on first UPS unit In case of sufficient output power the output will transfer to Inverter LED Alarm turn Off and the LED Operation must be is lit The synoptic diagram on first ...

Page 62: ... by the utility through the automatic bypass The booster starts automatically The synoptic diagram must display the status LOAD SUPPLIED BY AUTOMATIC BYPASS 3 Insert the inverter by pressing Inverter ON I key on first UPS unit In case of sufficient output power the output will transfer to Inverter LED Alarm turn Off and the LED Operation must be is lit The Synoptic diagram on first UPS unit must d...

Page 63: ...et Network and provides UPS information via the standard SNMP protocol The UPS can therefore be managed by a Network Management System NMS or by our applications for instance JUMP which uses this information to determine the state of the UPS in order to guarantee safe and orderly shutdown of the server when needed GE Power Diagnostics GE Power Diagnostics is an anytime anywhere concept in UPS stat...

Page 64: ...althy battery is essential to the performance of the UPS an automatic or manual battery test can be performed regularly to ensure failsafe operation in order to check if the battery can provide the expected backup time in case of utility failure We recommend the battery test be performed at least every 1 month especially if the battery is not sufficiently discharged during normal operation Since t...

Page 65: ...erating Manual LP 33U Series 30 40 kVA 10 NOTES 10 1 NOTES FORM It is recommended to note in this section Notes with date and short description all the operations performed on the UPS as maintenance components replacement abnormal situations etc Date Description Done by ...

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