Sungrow ST2752UX Manual

Liquid-cooling
Energy Storage SystemsOperation
& Maintenance InstructionLiquid-
cooling ESS O&M Instruction-OEN-
Ver11-202208
Operation & Maintenance Instruction
Liquid-cooling Energy Storage Systems
Liquid-cooling ESS O&M Instruction-OEN-Ver11-202208

I
All Rights Reserved
All Rights Reserved
No part of this document can be reproduced in any form or by any means without the prior
written permission of SUNGROW ENERGY STORAGE TECHNOLOGY CO., LTD (-
hereinafter "SUNGROW").
Trademarks
and other Sungrow trademarks used in this manual are owned by
SUNGROW.
All other trademarks or registered trademarks mentioned in this manual are owned by their
respective owners.
Software Licenses
• It is prohibited to use data contained in firmware or software developed by SUNGROW,
in part or in full, for commercial purposes by any means.
• It is prohibited to perform reverse engineering, cracking, or any other operations that
compromise the original program design of the software developed by SUNGROW.

II
About This Manual
This manual describes the commissioning, troubleshooting, and maintenance of the ESS.
Target Group
This manual is for operators of the power storage plant and qualified technical personnel.
The ESS must and can only be installed by professional technicians who meet the following
requirements:
• Has been trained
• Read this manual thoroughly and understand the safety instructions related to
operations
• Be familiar with local standards and relevant safety regulations of electrical systems
How to Use This Manual
Please read this manual carefully before using the product and keep it properly at a place
for easy access.
In order to provide customers with the best usage experience, the products and product
manuals are always in the process of improvement and upgrade. If the manual received is
slightly inconsistent with the product, it may be a result of product version upgrade, and the
actual product shall prevail.
Contents of the manual may be updated and amended continuously, so it is possible that
there may be some errors or slight inconsistency with the actual product. Please refer to the
actual product purchased, and the latest manual can be obtained from support.
sungrowpower.com or sales channels.
The figures in this manual are for reference only. The actual product received may differ.
Symbol Explanations
To ensure the safety of the users and their properties when they use the product and to
make sure that the product is used in an optimal and efficient manner, this manual provides
users with the relevant safety information highlighted by the following symbols.
Below is a list of symbols that are used in this manual. Review them carefully to make better
use of this manual.
Indicates an imminently hazardous situation which, if not avoided, will result in
death or serious injury.
Indicates a moderately hazardous situation which, if not avoided, will result in
death or serious injury.

III
Indicates a slightly hazardous situation which, if not avoided, may result in minor
or moderate injury.
Indicates a potential hazard which, if not avoided, will result in device malfunction
or property damage.
“NOTE” indicates additional information, emphasized contents or tips that may be
helpful, e.g., to help you solve problems or save time.
Symbol on Products
Always note hazard warnings on the machine body, including:
Marks Explanation
High voltage inside! Risk of electric shock by touching it!
This symbol indicates a protective ground terminal which needs to
be firmly grounded to ensure the safety of operators.
Read the instructions before performing any operation on the
product.
Live parts! Do not touch them until 5 minutes after disconnection
from the power sources.
Pay attention to the danger. Do not operate this product in the live
status!
Pay attention to heavy objects. Lifting of heavy objects may lead to
back injuries. Please lift heavy objects with appropriate tools.
Pay attention to explosion.
Pay attention to corrosion.
Do not dispose of this product as household waste.
No fire.
There should be a medical center nearby.

IV
Marks Explanation
In case of contact with eyes, rinse the eyes immediately with running
water or normal saline; and seek medical help in time.
It is required to wear goggles.
Abbreviations
Complete designation Abbreviations
Battery Energy Storage System BESS
Energy Storage System ESS
Battery Connection Panel BCP
Battery Supply Panel BSP
Power Conversion System PCS
DC/DC Converter DC/DC
Fire Suppression System FSS
Supervisory Control And Data Acquisition SCADA
Liquid Cooling System LCS
Local Controller LC
Energy Management System EMS
Switching Mode Power Supply SMPS
Battery Module PACK
Battery Cluster RACK
Battery Management Unit BMU
Battery Cluster Management Unit CMU
Battery System Management Unit SMU
Battery Management System BMS
Switch Gear S/G
State Of Charge SOC
State Of Energy SOE
State Of Health SOH
State Of Safety SOS

V
Unless otherwise specified, devices in this manual are referred to as the abbreviations
above.

VII
Contents
All Rights Reserved .....................................................................................................I
About This Manual......................................................................................................II
1 Introduction .......................................................................................................1
2 Commissioning .................................................................................................2
2.1 Inspection Before Powering up ........................................................................2
2.2 Powering on Steps .........................................................................................2
2.3 Pre-run Preparation ........................................................................................4
2.4 Commissioning ..............................................................................................4
2.4.1 Communication Commissioning .............................................................4
2.4.2 Charge-Discharge Commissioning .........................................................5
2.4.3 Charge-Discharge Cycle Commissioning ................................................5
3 Routine Maintenance .......................................................................................6
3.1 Precautions Before Maintenance .....................................................................6
3.2 Maintenance Item and Period ..........................................................................7
3.2.1 Maintenance (Every two years) ..............................................................7
3.2.2 Maintenance (Once a year)....................................................................7
3.2.3 Maintenance (Every half a year to once a year) .......................................8
3.3 Maintenance of Liquid Cooling System.............................................................9
3.4 Container Maintenance................................................................................. 11
3.4.1 Cleaning Container Appearance........................................................... 11
3.4.2 Checking Door Locks and Hinges.........................................................14
3.4.3 Checking Sealing Strips.......................................................................14
3.5 Battery Maintenance.....................................................................................14
3.5.1 Regular Maintenance and Maintenance Cycle.......................................14
3.5.2 Maintenance Precautions ....................................................................17
3.5.3 Maintenance.......................................................................................17
3.6 PCS Maintenance ........................................................................................19
3.6.1 Safety Rules .......................................................................................19
3.6.2 Maintenance and Interval.....................................................................19
3.6.3 Filter Checking and Cleaning ..............................................................22
3.7 Fire Suppression System Maintenance ..........................................................22

VIII
3.7.1 Overview ............................................................................................22
3.7.2 Visual Inspection.................................................................................23
3.7.3 Linkage Testing...................................................................................24
4 Common Maintenance Operations ..............................................................26
4.1 Coolant Filling and Drainage Operations ........................................................26
4.1.1 Coolant Replacement Intervals ............................................................26
4.1.2 Safety Precautions..............................................................................27
4.1.3 System Components Introduction.........................................................28
4.1.4 Coolant Filling and Drainage Kit ...........................................................29
4.1.5 System Drainage ................................................................................30
4.1.6 System Filling .....................................................................................32
4.2 Battery Module Replacement ........................................................................35
4.2.1 Preparation.........................................................................................35
4.2.2 Close the Valves of the Branch Lines on Both Sides...............................35
4.2.3 Connecting The Drainage Pipe.............................................................36
4.2.4 Tool Description ..................................................................................36
4.2.5 Replace the Faulty Pack ......................................................................37
4.2.6 Operation after Pack Replacement .......................................................46
4.3 BMU Replacement .......................................................................................46
4.4 Fuse Replacement .......................................................................................47
5 Troubleshooting ..............................................................................................49
5.1 Overview .....................................................................................................49
5.2 PCS Faults and Corrective Measures.............................................................49
5.3 BESS Faults and Corrective Measures...........................................................59
5.3.1 CMU Fault/Alarm List ..........................................................................59
5.3.2 BSC Fault / Alarm List .........................................................................65
5.3.3 LC Fault / Alarm List ............................................................................68
5.3.4 FSS Fault List .....................................................................................70
5.3.5 Temperature Control System Fault/Alarm List........................................72
5.3.6 DC/DC Fault List .................................................................................79
6 Appendix ..........................................................................................................93
6.1 Quality Assurance ........................................................................................93
6.2 Contact Information ......................................................................................93

1
1Introduction
The typical functional block diagram of ESS is shown below. The core equipment mainly
consists of PCS, medium voltage transformers, DC/DC converters, BCP, BSP, batteries,
battery management systems, energy management systems, local controllers, etc. The
auxiliary systems mainly consist of LCS, FSS, lighting systems, etc.
figure 1-1 Functional block diagram of ESS
*The above pictures are for reference only, please refer to the actual product received!

2
2Commissioning
2.1 Inspection Before Powering up
Before powering up the equipment, check the following items carefully.
• Check that the positive and negative wiring of the battery RACK and the DC/DC power
cable are correctly wired.
• Check that the battery RACK, DC/DC and battery terminal cabinet power circuit wiring
should not be loose.
• Check that there are no short circuits between the positive and negative terminals of the
converging branches in the BCP.
• Check that the external supply cable on the AC side of the BSP is wired correctly.
• The circuit breaker in the BSP and the load switches SWITCH1 & SWITCH2 on the DC/
DC should be in the open position.
• Check for coolant leaks in the battery PACK and in the cooling ducts.
• Confirm that the PCS DC side is correctly connected to the BCP DC side cable of the
BESS to avoid a reversal of the connection cable order.
• The guard inside the unit is securely mounted.
• The emergency stop button is in the released position.
• Check to ensure there is no earth fault.
• Check that the communication lines are in order according to the communication
diagram.
• Use a multimeter to check that the AC and DC side voltages meet the starting conditions
and that there is no risk of overvoltage.
• Check to ensure that no tools or parts have been left inside the appliance.
2.2 Powering on Steps
step 1 Power on the secondary circuit.
Before powering on, make sure that the temperature and humidity of the
debugging site are within the calibration range of the product nameplate.
1 Close the AC load switch of the transformer in accordance with the high voltage
operation specification.

3
2 Close the DC/DC load switches SWITCH1 and SWITCH2 in the BESS, close the
miniature circuit breakers of the BESS in turn according to the electrical drawings, and
check whether the voltage is normal. For specific steps, please refer to the system
manual of the specific project.
In the process of closing the circuit breaker, if the circuit breaker trips, check
whether the lower load is short-circuited.
step 2 Power on the main circuit.
1 Power on the BESS.
i. Confirm that all communication control devices such as DC/DC, system BSC, LC,
and switches have been powered on normally and have no faults.
ii. Close all DC/DC load switches SWITCH1 and SWITCH2 in the BESS in turn.
iii. The rest of the power-on operations of the system are automatic operations without
manual control.
If the BSC device address settings in the two BESSs conflict, first disconnect
the network cable from the BESS to the LC1000 cabinet, and re-assign the
device addresses according to the site address assignment requirements.
For the address configuration of LC and BSC devices, please refer to the
corresponding on-site software configuration and debugging files.
2 Power on the PCS.
• Manual closing operation of the DC load switch is prohibited.
• Make sure that the DC load switch is off before applying power to the DC
side.
• In off-grid situations, it is necessary to ensure that the DC load switch is in
stored energy when first starting the converter; otherwise, a manual
charging operation is required first.
i. Before starting up the PCS, ensure that the following requirements are met before
starting up the equipment.
• All connections are done by strictly following the installation manual and circuit
diagram.
• The protection cover inside the device has been installed securely.
Operation & Maintenance Instruction 2 Commissioning

4
• The emergency stop button is released and the Start/Stop switch is in Start
position.
• Grid main switch is in OFF position.
• Measure the DC and AC voltages with multimeter to check if they meet the PCS
startup requirements and there is no over-voltage hazard.
• The cabinet door is closed and the key is removed and stored by appointed
personnel.
ii. Starting up the PCS, please refer to the PCS manual configured for the specific
project for specific steps.
a). Make sure that the AC circuit breaker and DC load switch of the PCS are
disconnected.
b). Make sure the cables on the AC and DC side are connected correctly.
c). Measure the voltage of the battery to be connected to ensure it is within the
allowable range. Connect the battery to the DC side copper bar of the PCS.
d). According to the actual requirements of the site, close the internal power switch
Q3 or the external power switch Q2. Note that Q3 and Q2 cannot be closed at the
same time. After the power indicator is on, select the operation mode and
operation parameters on the web operation parameter interface as required. For
specific steps, please refer to the PCS manual configured for the specific project.
- - End
2.3 Pre-run Preparation
• Check and fix the faults displayed by the system after power-up.
• Verify that the software version is correct.
• Enter the web interface of the BSC and LC respectively to confirm that the parameter
profiles are correct and that modifications to the configuration parameters are prohibited.
2.4 Commissioning
2.4.1 Communication Commissioning
step 1 Re-allocate the addresses of each sub-device according to the on-site address allocation
requirements.
step 2 Read battery RACK, BSC, LC data through the background monitoring interface, and it
should be able to read normally.
step 3 DC/DC stop/start commands and PCS stop/start commands are issued through the
background monitoring interface, which should be able to achieve corresponding functions.
step 4 Modifying the control parameters through the background monitoring interface should be
able to achieve the corresponding functions.
- - End
2 Commissioning Operation & Maintenance Instruction

5
2.4.2 Charge-Discharge Commissioning
step 1 Control the PCS startup through the background monitoring interface, close the ring network
cabinet, issue the PCS startup command, the PCS should be able to start normally, and
issue the PCS shutdown command, the PCS should be able to stop normally.
step 2 Through the background monitoring interface, take 100kW as the step, increase the PCS
power to the actual maximum dischargeable power, run for 10min, the intelligent unit board
should be able to distribute the power to the PCS normally. Observe that the voltage, current,
temperature and other parameters of the battery RACK in the battery container should be
normal. Observe all DC/DC voltage, current, and device temperature rise parameters. There
should be no abnormality. Observe PCS voltage, current, and device temperature rise
parameters. Set the PCS power to 0kW.
step 3 Through the background monitoring interface, take 200kW as the step, increase the PCS
power to the actual maximum rechargeable power, run for 10min, the intelligent unit board
should be able to distribute the power to the PCS normally. Observe that the voltage, current,
temperature and other parameters of the battery RACK in the battery container should be
normal. Observe all DC/DC voltage, current, and device temperature rise parameters. There
should be no abnormality. Observe PCS voltage, current, and device temperature rise
parameters.
step 4 Set a battery SOC upper limit value, charge with the actual maximum power that can be
charged, and observe that when the set SOC upper limit value is reached, the DC/DC
corresponding to RACK should be in a hot standby state.
step 5 Set a battery SOC lower limit value, discharge with the power that can actually discharge
the maximum power, observe that when the set SOC lower limit value is reached, the DC/
DC corresponding to RACK should be in a hot standby state.
step 6 The background monitoring interface issues the PCS startup command, the PCS should be
able to start normally, and the communication between the background and the PCS should
be cut off, and the PCS should be able to stop.
- - End
The upper/lower limit values set in steps 4 and 5 refer to the actual state of charge
of the battery RACK, select a value that can be reached in a short time, and
change the parameter back to the original setting value after the test is completed.
2.4.3 Charge-Discharge Cycle Commissioning
step 1 The background monitoring performs a full charge and full discharge cycle to calibrate the
battery SOC according to the actual charge/discharge situation of the battery RACK in the
battery container.
step 2 Observe that the voltage, current, temperature and other parameters of the battery RACK
during the charging and discharging process should be normal.
step 3 Observe that the PCS voltage, current, and device temperature rise parameters should be
normal.
- - End
Operation & Maintenance Instruction 2 Commissioning

6
3 Routine Maintenance
3.1 Precautions Before Maintenance
• Do not open the door to maintain the batteries in rainy, humid or windy days.
SUNGROW shall not be held liable for any damage caused by violation of the
warning.
• Avoid opening the container door when the humidity is high in rain, snow or fog,
and make sure that the seals around the container door do not curl when the
door is closed.
In fair weather, it is recommended to open the container door to dehumidify the
equipment.
• To avoid electric shock, do not perform any other maintenance operations
beyond this manual.
• If necessary, contact SUNGROW customer service for maintenance.

7
3.2 Maintenance Item and Period
3.2.1 Maintenance (Every two years)
Item Check method
System status
and cleaning
Check the following items, and correct immediately those failing to
meet the relevant requirements:
• Check whether there is any damage or deformation of the
container and internal devices.
• Check if there is abnormal noise during operation of internal
devices.
• Check whether the temperature in the container is excessively
high.
• Check whether the humidity and the amount of dust inside the
container are within the normal range. Clean the equipment if
necessary.
• Check whether the air inlet and outlet of the BESS are blocked.
Warning marks Check whether the warning labels and marks are clearly visible and
free of stains and damage. Replace them if necessary.
Ground of the
shielded layer of
cables
Check whether the cable shielding layer is in good contact with the
insulation sleeve and whether the copper bus bar is firmly fixed.
Surge protection
device and fuse Check whether the SPD and fuse are properly fastened.
Corrosion Check whether there is oxidation or rust inside the container.
3.2.2 Maintenance (Once a year)
Item Check method
Outside the
container
Check the following items, and correct immediately those failing to
meet relevant requirements:
• Check whether there are flammable objects on the top of the
container.
• Check whether the welding points between the container and the
foundation steel plate are firm and whether there is corrosion.
• Check whether there is any damage, flaking paint or sign of
oxidization on the enclosure.
• Check whether the lock of the cabinet door can be unlocked
flexibly.
• Check whether the sealing strip is fixed properly.
Inside the
container
Check whether there are foreign objects, dust, dirt, and condensed
water inside the integrated energy storage system.
Operation & Maintenance Instruction 3 Routine Maintenance

8
Item Check method
Air inlet and outlet
Check the temperature of the radiator and the amount of dust
accumulated. Clean heat-dissipation modules with a vacuum
cleaner if necessary.
Wiring and cable
layout
Completely power off the devices inside the BESS before checking.
For any non-conformances found during inspection, correct them
immediately.
• Check whether the cable layout is normal and whether there is a
short circuit. For any non-conformances found during inspection,
correct them immediately.
• Check whether all cable entry are well sealed.
• Check whether there is water seepage inside the BESS.
• Check whether the power cables are loose, and fasten them
again by the torque specified previously.
• Check whether the power cables and control cables are
damaged, especially if the surface contacting the metal surface is
cut.
• Check whether the insulation tapes on the power cable terminals
fall off.
Ground
connection and
equipotential
connection
• Check whether the ground connection is correct and the
grounding resistance shall be no more than 4Ω.
• Check whether the equipotential connection inside the integrated
BESS is correct.
Fan
• Check the running status of fans.
• Check whether fans are blocked.
• Check if there is abnormal noise during operation of the fans.
Screw Check whether internal screws fall off.
3.2.3 Maintenance (Every half a year to once a year)
Item Check method
Safety function
• Check whether the shutdown key on the touchscreen and the
emergency stop button work normally.
• Simulate shutdown.
• Check the warning marks and other device marks, and replace
them timely when they are fuzzy or damaged.
Software
maintenance Check the settable parameters on the Web.
3 Routine Maintenance Operation & Maintenance Instruction

9
Item Check method
Internal
components
inspection
• Check the cleanness of the circuit board and other elements and
components.
• Check the temperature of the radiator and the amount of dust
accumulated. Clean heat-dissipation modules with a vacuum
cleaner if necessary.
• Replace the air filter screen when necessary.
Note! It is necessary to check ventilation of the air inlet.
Otherwise, fault may occur due to overheating if the module
cannot be cooled effectively.
Device
maintenance
• Carry out regular inspection for corrosion of all metal components
(once per half a year).
• Check the contactors (auxiliary switches and micro-switches)
annually to ensure the good mechanical operation.
• Check the running parameters (especially voltage and insulation).
3.3 Maintenance of Liquid Cooling System
The following provides the recommended maintenance periods. The actual maintenance
period shall be adjusted reasonably in consideration of the specific installation environment
of the product.
Factors like the power plant scale, the location, and the site environment can affect the
maintenance period of the product. It is necessary to shorten the maintenance period and
increase the maintenance frequency in the event of heavy sandstorm or dust in the
operation environment.
Operation & Maintenance Instruction 3 Routine Maintenance

10
Item Content Check method Maintenan-
ce tools
Fan Check whether the fan blades
cannot rotate or are damaged. If
so, replace the fan.
1. The fan blade rotates
smoothly without
abnormal noise;
2. No damage to fan
blade. Note: Check this
item at least half a year.
Blade damage inspection
is not mandatory.
Screwdriver
with long
handle
Water
pump
1. Check whether over 5% of the
cooling air inlet hole of the water
pump is blocked. If so, clear it
with a brush;
2. Visually inspect the pump
body (not the joint parts) and
check whether there is obvious
water dripping (except
condensate). If so, replace the
sealing ring of the pump.
1. The water pump runs
smoothly without
abnormal noise;
2. There is no obvious
dripping on the pump
body (except
condensate).
Brush
Water
system
Check the high and low pressure
of the water system through HMI.
The high pressure should be
2.8bar and the low pressure
should be 0.2 bar.
1. If the high pressure is higher
than 2.8bar, check whether the
filter of the water system is dirty
and blocked;
2. If the low pressure is lower
than 0.2 bar, replenish the water
in the system.
High pressure < 2.8bar;
Low pressure ＞0.2 bar
Slotted
screwdriver,
Phillips
screwdriver,
water pump,
water pipe,
clamp.
If the BESS has a "communication failure or failure of the liquid-cooled unit",
please contact the after-sales service personnel in time to ensure the functional
integrity of the system.
3 Routine Maintenance Operation & Maintenance Instruction