Chapter 2 Battery Installation
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MUST400_User manual_EN_REV02 User Manual
For defining the battery charging current follow the formula here below:
I = (n * P[W] * Charge I(%) / 100) / 576V
Charge I(%) = (I * 576 * 100) / (n * P[W])
Where:
I is the battery charging current
n is the number of module inserted in the system
P[W] the power of the module inserted in the system
Charge (I%) is the value inserted in the battery setting menu
Example:
One power module of 20kVA setting Charge I(%)=20 gives:
I= (n*P[W]*ChargeI%)/576V=(1*18000*20/100)/576= 6,25A max
Table. 2- 1: Battery charging current
2.2.5 Advanced battery Functions (Software Settings Performed by the Commissioning
Engineer)
Battery self-test and self-service
At periodic intervals, 25% of the rated capacity of the battery will be discharged automatically, and the actual
load must exceed 25% of the rated UPS (kVA) capacity. If the load is less than 25%, auto-discharge cannot
be executed. The periodic interval can be set from 720 to 3000 hours.
Conditions: Battery at float charge for at least 5 hours, load equal to 25~100% of rated UPS capacity
Trigger
—
Manually through the command of Battery Maintenance Test in LCD panel or automatically Battery
self-test interval.
Battery Low Pre-warning
The battery undervoltage pre-warning occurs before the end of discharge. After this pre-warning, the battery
should have the capacity for 3 remaining minutes discharging with full load.
End of discharge (EOD) protection
If the battery voltage is lower than the EOD, the battery converter will be shut down. EOD is adjustable from
1.6V to 1.75V per cell (VRLA).
Battery
menu
parameter
20kVA
10kVA
[A]
[A]
3
1
0,5
5
1,5
0,8
10
3,1
1,5
15
4,5
2,3
20
6,2
3,1
Recharging current
for each power
module
Charge I(%)
