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Slow charging of new batteries

I have recently replaced my 6 5year old leisure batteries with 3 new ones and am having trouble charging them.
What reason would my alternator charge at a low ampage (at 5amps) into the bank of the 3 new batteries (all 110 amp)which hadbeen discharged by at least 70 amps?
The old batteries were charging normally,for old batteries,before they were taken out.
The new batteries are numax brand,sealed.
Thanks very much,
Rachel welton.

Asked by: rachel welton  | 6.43pm, Thursday 19 April

WW says:

When you fitted the new batteries did you replace all the wires exactly as they were before? It sounds as if the alternator might be the remote sensing type, and the voltage sensing wire, which is quite small and insignificant, has been left off.
If the wiring is identical to before, check that the 'Ignition' or 'charge warning' light is working correctly. This should come on when the engine is not running, and go out when the alternator is working correctly. If this is not working the alternator will only charge at a low rate.
Best of luck.

Rupert Smedley  | 10.13AM, Friday 20 April

I also wondered if the shunt for the ammeter was correctly reconnected as well- though that is a long shot. If it was not correctly positioned, then it would give a false reading.

Mark Langley  | 10.46AM, Friday 20 April

Readers say:

Thank you,mark or rupert,not sure who answered,i will check as you advise and go from there.most grateful for your tine in answering,

rachel welton  | 9.04AM, Monday 23 April

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