The BMS monitors the battery pack temperature through four (4) thermistors directly connected to the main unit. If additional thermistor monitoring is necessary, the Thermistor Expansion Module can be connected to monitor up to 80 additional thermistors, and as many as 10 thermal modules can be used together to monitor 800 thermistors total.
The thermal interface also includes the ability to control an external fan. The controller can be configured for on/off operation or for a variable fan speed using a PWM output. For reliability reasons, the fan driver is external to the BMS and is optional. The fan controller interface includes a fan monitoring circuit which monitors for a malfunctioning cooling fan and can set error codes if a fault is detected.
The fan can be configured both to cool the battery when hot and to warm the battery when warmer ambient air is available. All thermal settings are programmable.