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Re: Battery charger voltage

Posted: Tue Dec 04, 2018 1:36 pm
by theoldman
Some bright spark "borrowed" the batteries from our class 31 loco to get their Class 25 moving. They failed to return them and the loco sat for 18 months with them still in it.

On eventually recovering them, it was found that 12 were absolutely shot and a further 9 were "borderline".

The man from Shield said they sulphate when left, but sometimes can be rejuvenated. We didn't take a chance and bought a new set.

If you think car batteries are expensive, the set cost us the best part of five grand! :o

Re: Battery charger voltage

Posted: Tue Dec 04, 2018 1:56 pm
by John-B
Stick to steam power, it's more reliable and you don't need batteries. :D

Re: Battery charger voltage

Posted: Tue Dec 04, 2018 2:17 pm
by Sydsmith
An expensive mistake Neil and one that can catch us all out, the enemy of all lead acid batteries is for them to be left under charged particularly for long periods.

Sulphate starts to form as soon as a battery is static, not being charged or discharged, and under it's full charge voltage.

In the past with dynamo charging it was typical for a car to be started on a cold day and not run long enough for the battery to be replenished, we used to say 10 miles without lights on, that got worse on the return journey and the problem multiplied, hence up until alternators, car batteries became clogged with lead sulphate and only lasted on average 2-3 years.

Since alternators were introduced the higher level of charge, even at tick over, has enabled batteries to become fully recharged on quite short runs, a typical petrol car can recover full battery charge in 2-3 miles so batteries can and do ,as I have experienced myself last 15-16 years or more.

The secret is as I said in an earlier reply is to splash out on smart chargers that trickles batteries up to full charge then drop out until the voltage falls again, when they cut back in.

Solar charges are ideal to keep batteries topped up if they can be rigged up to do so. Syd