Current drain testing

[pcatterall]

I suspect that there is some drain on my batteries. My instrument panel has an ammeter but I have no way of monitoring for drain.
What is the best simple test to check, can I find out if anything is being used when all the equipment is switched off.
(I do have a digital multimeter)
Thanks, Peter

 

[William_H]

Your digital multimeter will have ranges of 20 milliamps or perhaps 2 milliamps. Make sure everything is turned off then remove one battery lead and fit the multimeter on milliamp range between the battery and the removed terminal. You should have no discernable current ie less than 1 milliamp. Any more is unwanted leakage.
Make sure your memeory for the FM radio is disconnected and try switching off/disconnecting bilge pump.
It may be safest to test on 2 amp range first as any high current can blow the fuse in the multimeter.
good luck olewill

 

[pampas]

Note, if Neg earth place, meter in the neg earth to engine between common and engine and use if possible a anolouge meter,ranged at first on your voltage system. With everything normally switched off see if there is a voltage, if so think about systems that have memory circuits and disconnect ,then go to the current range set at about 1-5 amps dab one end and look for a deflection, come down in range until you can detect you fault.

Sounds hard but is easy to do, use voltage range first as it will protect you and the instrument in use. Good hunting. Pampas