GRAUPNER POLARON PRO Operating Manual page 84

A Bat. Temp Too Low error message indicates that the battery
temperature is too low to operate using the charging process.
A Bat. Temp Too High error message indicates that the he battery
temperature exceeds the preset temperature values.
An Internal Temp. error message indicates that the internal
temperature within the charger exceeds the recommended operating
conditions.
A BLC Volt High error message indicates that the balancer cell voltage
exceeds the recommended operating conditions.
A BLC Volt Low error message indicates that the balancer cell voltage
is below the recommended operating conditions.
A Calibration error message indicates that threre is a fault in either
the default calibration data or the internal circuits of the charger.
A No Sensor error message indicates that the temperature sensor has
been disconnected.
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