Why does an external voltmeter, when connected across my battery, always read a different voltage than the value displayed on the CASP?
When charging (or discharging) a battery, the CASP turns off the current to (or from) the battery for 10 milliseconds each second, to measure the battery voltage. During this 10msec period when no current is flowing, the CASP is able to read the true open circuit battery voltage. Synchronizing the voltage measurement with this “quiet” period eliminates any possibility of IR drop errors in the interconnecting cables, which a regular voltmeter is incapable of doing.
Related Questions
- Why does an external voltmeter, when connected across my battery, always read a different voltage than the value displayed on the CASP?
- Does A Voltmeter Have High Or Low Internal Resistance Compared To The Battery Voltage Across Which It Measures?
- Voltmeter should display control unit operating voltage*. Voltage value okday?
