Battery Capacity Check

A fully functioning battery is important. A battery may be showing correct terminal voltage when checked with a multimeter but that gives no idea of its capacity to deliver sustained current over time.

The battery capacity tester discharges the battery at a specified current over a specified time.

Normally done during an Annual Inspection but can be done at any time. We can test suspect batteries ( 12V and 24V up to 59 Ah).

Battery problems should be checked in relation to the alternator and regulator also, as if these are defective the battery will not be charged correctly or at all.

Note the above is strictlyon an "on the aircraft" basis. Ref ML.A.502 (b).