Vertiv Liebert APM Plus - 7.5 Battery Installation Environment and Number of Batteries

7.5 Battery Installation Environment and Number of Batteries
7.5.1 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 x n x I
gas
x C
rt
x 10
–3
[m
3
/h]
Where:
Q- The fresh air ventilation volume per hour, the unit is m
3
/h
n- Number of cells
I
gas
- The current producing gas under battery float charging or boost charge conditions, the unit is mA/Ah
I
gas
=1, under the float charging condition of 2.27 V/cell
I
gas
=8, under the boost charge condition of 2.35 V/cell
C
rt
- 20 hr battery rated capacity
Temperature
Typ e Tem perature value Rem a rk
Recommended optimal
temperature
20 °C to 25 °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.
Short time allowable
temperature
-15 °C to 45 °C
Table 7.1 R ang e of am bient tem p erature
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 of less than 90%, and be protected from the heat
source and direct sunshine.
The ambient temperature, ventilation, space, float/boost 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 the valve-
regulated battery shall be used in 15 °C to 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 to 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.
7 Battery
115
Vertiv™ Liebert® APM Plus User Manual