Customer is using 2 UPS5000E 120 KVA HABBS, both UPS have the same configuration and the same number of batteries connected (3 battery strings (40 batteries X 3 strings 150 AH each UPS) but the displayed backup time is very different even if the load percentage is almost the same :
Also, these are 2 independent systems, not parallel connection.
Pictures below :
UPS A Backup time 647 MIN - 100% percent charged, 17.9% load
UPS B - backup time 239 min , 100 percent charged / 13.7%load
No alarm information, customer just noticed that 2 UPS with the same configuration and battery strings connected have very different backup time.
1. Asked customer to show the battery settings parameters page and find out that the battery installation time was 01.01.2014 on both UPSs.
2.Asked customer to put the real Installation Time (02.04.2018). After customer changed the parameter we notice change in UPS backup time and charging percentage (images below)
UPS B after changing Installation time on the batteries : Charging changed from 100% to 73% and backup time go to 699 min
UPS A after changing Installation time on the batteries : Charging changed from 100% to 71% and backup time go to 208 min
After Installation time settings set correctly we can still see a big difference between backup time of the 2 UPS
3. Asked customer to show the Number of cells settings and battery capacity settings.
On UPS A the Number of cells was set correctly ( 40 batteries * 6 cells = 240 cells) and the battery capacity 450 AH (3 battery strings 150 AH connected in parallel) - image below
On UPS B the Number of cells was set wrongly ( 40 batteries * 6 cells = 240 cells) and the battery capacity 150 AH (image below)
4. Asked customer to modify the Battery capacity on UPS B from 150 AH to 450 AH. After modification of battery capacity parameter the UPS showed good backup time.
UPS A after good settings : 72% charged and 770 min backup time
UPS B after good settings : 73% charged and 707 min backup time
Root cause :
Customer did not followed the Huawei guide in order to set the battery parameters.
On UPS A customer did the good settings : 240 Cells and 450 AH ( 40 batteries * 6 cells = 240 cells) / (3 battery strings 150 AH connected in parallel)
On UPS B customer did wrong settings : 240 cells and 150 AH - the customer didn't keep the same setting and did not add the battery capacity * each string
Also, the Installation Time on the batteries was not correctly set and because of this the UPS showed 100% charging percentage of the batteries
Solution for this case was to check the battery parameters one by one and to compare the two UPSs settings in order to find the difference.
After finding the fault, modify the settings to the correct ones.
Always customer should follow Huawei guidance in order to set the battery parameters. Incorrect settings could lead to battery short lifespan.