Chapter 6 Battery 63
NX UPS Single Module And Parallel System 250kVA ~ 800kVA User Manual
6.4 Precautions For Installation Design
Note
Precautions for installation, use and maintenance of the battery are described iin the relevant battery manual provided by the
battery manufacturer. The safety precautions described in this section include the important matters that must be considered
during the installation design. The design results may be changed according to the local situations.
6.5 Battery Installation Environment And Number Of Batteries
6.5.1 Installation Environment:
Fresh air volume (EN50272-2001)
The operating environment of the battery must be ventilated. During the operation of the battery, the following
requirement for the fresh air ventilation shall be satisfied:
Q=0.05×n×Igas×Crt×10
–3
[m
3
/h]
Where:
Q
―
The fresh air ventilation volume per hour, the unit is m
3
/h
n
―
Number of cells
Igas
―
The gas evolving current density under battery float charging or equalizing charge conditions, the unit is mA/Ah
Igas=1, under the float charging condition of 2.27V/cell
Igas=8, under the equalizing charge condition of 2.35V/cell
Crt
―
20hr battery rated capacity
Temperature
Table 6-1 Ambient temperature range
Type
Temperature value
Remark
Recommended
optimal temperature
20°C ~ 25°C
Short time
allowable
temperature
-15°C ~ 45°C
The ambient temperature for the battery operation shall not be too high or too low.
If the average operating temperature of the battery rises from 25°C to 35°C, the
service life of the battery will be reduced by 50%. If the operating temperature of
the battery is over 40°C, the service life of the battery will be reduced
exponentially each day
The higher the temperature is, the shorter the battery service life will be. At low temperature, the charge/discharge
performance of the battery will be significantly reduced.
The battery must be installed in cool and dry environment with the humidity less than 90%, and be protected from the
heat source and direct sunshine.
The ambient temperature, ventilation, space, float/equalizing charge voltage and ripple current will affect the battery
temperature. Uneven temperature among the battery strings will cause uneven voltage distribution and thus result in
problem. Therefore, it is very important to maintain balanced temperature in the battery string, and the temperature
difference between batteries of different layers shall be kept within 3°C. Valve-regulated battery is very sensitive to
the temperature, therefore, valve-regulated battery shall be used in 15°C ~ 25°C. If the battery cabinet is installed
near the UPS, the maximum design ambient temperature shall be determined according to the battery rather than the
UPS. That is, if valve-regulated battery is used, the indoor ambient temperature shall be 15°C ~ 25°C rather than the
operating temperature range of the main equipment. Under the precondition that the average temperature will not
exceed 25°C, it is allowed to have short time temperature deviation.
6.5.2 Number Of Batteries
The battery number, EOD voltage, float charging voltage under the 380V/400V/415V voltage systems are consistent,
as shown in Table 6-2.