Battery Information
B–14 975-0012-01-02 Rev A
Temperature compensation is based on battery type — 5 mv/cell for lead acid type batteries and 2 mv/cell for alkaline type batteries (NiCad or NiFe). The temperature compensation calculations are derived from TableB-5.Table B-4Variances in Charging Voltage based on Battery Temperature
Temperature
(around the BTS) 12-volt units 24-volt units 48-volt units
Celsius Fahrenheit
Lead Acid
(6 cells)
NiCad
(10 cells)
Lead Acid
(12 cells)
NiCad
(20 cells)
Lead Acid
(24 cells)
NiCad
(40 cells)
60 140 -1.05 -0.70 -2.10 -1.40 -4.20 -2.80
55 131 -0.90 -0.60 -1.80 -1.20 -3.60 -2.40
50 122 -0.75 -0.50 -1.50 -1.00 -3.00 -2.00
45 113 -0.60 -0.40 -1.20 -0.80 -2.40 -1.60
40 104 -0.45 -0.30 -0.90 -0.60 -1.80 -1.20
35 95 -0.30 -0.20 -0.60 -0.40 -1.20 -0.80
30 86 -0.15 -0.10 -0.30 -0.20 -0.60 -0.40
25 77 0.00 0.00 0.00 0.00 0.00 0.00
20 68 0.15 0.10 0.30 0.20 0.60 0.40
15 59 0.30 0.20 0.60 0.40 1.20 0.80
10 50 0.45 0.30 0.90 0.60 1.80 1.20
5 41 0.90 0.60 1.20 0.80 2.40 1.60
0 32 0.75 0.50 1.50 1.00 3.00 2.00
-5 23 0.90 0.60 1.80 1.20 3.60 2.40
-10 14 1.05 1.20 2.10 1.40 4.20 2.80
-15 5 1.20 0.80 2.40 1.60 4.80 3.20
-20 -4 1.35 1.40 2.70 1.80 5.40 3.60
-25 -13 1.50 1.00 3.00 2.00 6.00 4.00
-30 -22 1.65 1.10 3.30 2.20 6.60 4.40
-35 -31 1.80 1.20 3.60 2.40 7.20 4.80
-40 -40 1.95 1.30 3.90 2.60 7.80 5.20
Table B-5Temperature Compensation Calculation
Battery Type 24-volt Systems 48-volt Systems
Lead Acid 0.060 volts (60 mV) per
degree Celsius
0.120 Volts (120 mV) per degree
Celsius
NiCad 0.040 volts (40 mV) per
degree Celsius
0.080 volts (80 mV) per degree
Celsius
Important:
If the battery temperature is allowed to fall to extremely cold
temperatures, the inverter with a BTS may not be able to properly recharge cold
batteries due to maximum voltage limits of the inverter. Ensure the batteries are
protected from extreme temperatures.