Operation
975-0125-02-01 2–17
Charger Operation with Battery Temperature Sensor
Since battery temperature is a key factor in optimal charging, the house battery
charger voltage will be adjusted ( automati call y and conti nuously ) acc ording t o the
actual battery temperature to ensure that the house battery is fully charged, but not
overcharged. For this reason, Xantrex has included a battery temperature sensor
(see Figure 2-11) with your MS2000 Sine Wave Inverter/Charger that allows the
main charger to provide this temperature-co mp e nsa te d charg e form ula. The Echo
Charger output bank is not temperature compensated.
The battery temperature sensor continuously measures the temperature of the
house battery and adjusts the main charger output for a more accurate,
temperature-compensated ch arge.
When batteries are cold, t heir chemical reaction is sluggish, meaning they d on’t
absorb charge as easily. Thus a charge level optimized for room temperature will
not charge the batteries sufficie ntly if they are cold. Th e main charger must
compensate by increasing its voltage to achieve the compensated equivalent of a
room temperature charge.
If the batteries are hot, the chemical reaction is hyperactive and they absorb
energy too easily; thus a standard room-temperature charge would tend to
overcharge a hot battery. Therefore, the main charg er compensa tes by reducing its
voltage.
The battery temperature sensor automatically, and continuously, makes
adjustments to the main charger’s voltage setpoints to properly charge your
batteries. The actual charge compensation formula can be found on pageA–3.
If a battery temperature sensor is not present, the MS2000 uses the cold, warm,
and hot settings. Charging may not be effective at extreme temperatures. See
“Main Charger Specifications ” on page A–3.
Important:
It is normal to see a voltage that is different than the specified
setpoint when charging if the battery case temperat ure is above or below 77 °F
(25 °C)
Figure 2-11
Battery Temperature Sensor