Battery Temperature Sensor Operation; Figure 3-2, Bts Temperature To Charge Voltage Change - Magnum Energy MMS Series Owner's Manual

Operation
3.2

Battery Temperature Sensor Operation

The plug-in Battery Temperature Sensor (BTS) is used to determine
the battery temperature around the batteries. This information allows
the multi-stage battery charger to automatically adjust the battery
charge voltages for optimum charging performance and longer
battery life.
When the BTS is installed, if the temperature around the BTS is below
77°F (25°C) the absorb and fl oat charge voltage increases. If the
temperature around the BTS is higher than 77°F (25°C), the absorb
and fl oat charge voltage decreases. See Figure 3-2 to determine how
much the charge voltage changes (increases or decreases) as the
temperature reading of the BTS changes. For example, the nominal
absorb charge voltage for a fl ooded battery at 77°F (25°C) is 14.6
VDC. If the battery temperature is 95°F (35°C), the absorb charge
voltage would decrease to 14.3 VDC (14.6 VDC - 0.3 change).
If the temperature sensor is NOT installed, the charge voltages will
not be compensated and the battery will maintain the charge it had
at a temperature of 77°F (25°C). The life of the batteries may be
reduced if they are subjected to large temperature changes when
the BTS is not installed.
Info: When the BTS is connected, the battery charger
uses a value of -5mV/°C/Cell from 0-50°C to change the
charge voltage based on temperature.
Temperature Compensation using BTS
12VDC units
+0.75V
+0.6V
+0.45V
+0.3V
+0.15V
No Change
-0.15V
-0.3V
-0.45V
-0.6V
-0.75V
0C
32F

Figure 3-2, BTS Temperature to Charge Voltage Change

34
5C 10C 15C 20C
41F 50F 59F 68F
Temperature reading from BTS
no BTS
connected
25C 30C 35C 40C 45C
77F 86F 95F 104F 113F
© 2017 Sensata Technologies
50C
122F