Sentry-2412 (BatteryDAQ) detected a high Internal Resistance for one battery while voltage is normal.
|Voltage (V)||Internal Resistance (milliohm)|
Tried to verify with a portable battery tester, it won’t measure correctly for this battery.
Battery looks perfect from front view but it has a crack on the side.
Measured with a multimeter, this battery has about 800mV AC ripple on posts while others only 10mV.
Most portable testers utilize AC method for lower cost, they cannot work with high ripple input due to the signal range limit. They may give wrong result or random data for a bad battery like this one when measure it online.
All BatteryDAQ’s product utilize the proprietary pulsed DC technology. It costs more in production but ensures consistent data for online measurement crossing wide range UPS and charging systems.