Charging batteries from the mains feed

Technical questions and answers about the Mazda Bongo

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Charging batteries from the mains feed

Post by Ollymuk » Sat Aug 01, 2020 7:37 pm

Lo all

Broadly speaking what's required to charge the batteries from the mains feed?

Currently I have the mains socket, which connects to a consumer unit with and RCD or two. This goes to two mains plugs underneath the 12v switch panel (switches and USB ports). However the 12v feed doesn't meet the mains feeds at all. With mains coming in the voltage on the LB doesnt change.

If I wanted to charge the batteries from the mains feed, I'm assuming I have to leave the consumer unit, but replace the 12v panel with one that has a step down transformer which can put 14v from the mains feed to the 12v circuit?

If that's right, what's the name of the panel that I need?

If it's not right, where have I gone wrong?

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Re: Charging batteries from the mains feed

Post by g8dhe » Sat Aug 01, 2020 10:28 pm

Generally something like a PMS3 would be fitted from scratch this is a consumer unit and 12 volt system including a charger/power pack ... SwtAlbo2qB
Another common option is a Zig Marque 1 with a separate power pack like this one ... 2749.l2649

Both systems supply "float" charge voltage of around 13.7 volts to maintain the battery and run the 12 volt system when static.
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Re: Charging batteries from the mains feed

Post by Rickster » Sun Aug 02, 2020 2:19 pm

I just went with the simple route, a separate charger connected to the 6A breaker on the consumer unit, the wiring used to the battery was the existing rear fan wires, these are rated upto 30 amps, the wire in the front end was removed from the fuse box, extended, inline fused and connected to LB.
The above may seem a bodge but the fan unit is no longer In the back, the wires are already in existence, why make life harder?
It's another thing having to run a new feed though.