Discharge Testing - Hammerhead Charger 48V Operator's Manual

TROJAN BATTERY USER'S GUIDE

Discharge Testing

7.5.
• Connect and start discharger
• Record the runtime (minutes) when discharge is complete
• Correct runtime minutes for temperature using the following formula (valid between
24°C (75°F) and 32°C (90°F):
o Mc = Mr [1 – 0.009 (T - 27)] where Mc is the corrected minutes, Mr is the
minutes recorded and T is the temperature at the end of discharge in °C
• If the discharge time is greater than 50% of the batteries' rated capacity then all the
batteries are operational
• Reconnect the discharger to record the individual battery voltage while still under
load (current being drawn)
• If the discharge runtime is less than 50% of the batteries' rated capacity, the
batteries with a voltage that is 0.5V lower than the highest voltage may be a failed
battery
There are other methods of testing batteries including internal resistance (i.e. CCA testers)
and carbon-pile discharge testers. However these are not suitable testing methods for deep
cycle batteries.
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