DIY Doctor UK DIY Forums

Hi, I have a catering trailer that is connected to mains power. I want to run a small water pump for sink but most of the caravan pumps are 12v and run off the caravan battery (which I dont have).. I would prefer to wire the pump into the mains via a fused switch also connected to my water heater so they are both on at the same time.

The pump I have is inline, self priming on demand so it will self activate when the taps are turned on. However being 12 v it really only offers the option to connect it to a car batter.. (black/red wires) ... is there a small transformer/connverter that can be used inline to convert the mains power to 12v (i.e LED lighting tranformer for example)... ? tks

Yes there is such a thing you are looking for.
As for which one that depends on how much current your pump draws (You don't say)
That said you can always get one which can supply more current than is required as the pump will only draw what it requires.
If you buy a 12v D.C. "wall wart" instead of using a spur, you could use a socket and plug the wall wart into that.
Do be sure the wall wart you choose says 12v DC output, not 12v output.

I used a CB power supply in my caravan however at that time there were no LED lamps needing a 12 volt DC supply, so yes today they would seem to be the easy way to get 12 volt DC.

embecmom2 wrote:Hi, I have a catering trailer that is connected to mains power. I want to run a small water pump for sink but most of the caravan pumps are 12v and run off the caravan battery (which I dont have).. I would prefer to wire the pump into the mains via a fused switch also connected to my water heater so they are both on at the same time.

The pump I have is inline, self priming on demand so it will self activate when the taps are turned on. However being 12 v it really only offers the option to connect it to a car batter.. (black/red wires) ... is there a small transformer/connverter that can be used inline to convert the mains power to 12v (i.e LED lighting tranformer for example)... ? tks

Thanks for info, the pump only draws 4.5amps, and the whole connection shouldnt be over 15 amps. .. Id prefer just to wire something in place as sockets are at a premium.

4.5 Amps for a 12v pump is quite a lot, are you sure that is correct?

If it is, then you will have to buy a 12v power supply. There are quite a few available. But if you get one of the "chassis" type I would strongly suggest mounting it in a suitable plastic box.

Mr White wrote:4.5 Amps for a 12v pump is quite a lot, are you sure that is correct?

If it is, then you will have to buy a 12v power supply. There are quite a few available. But if you get one of the "chassis" type I would strongly suggest mounting it in a suitable plastic box.

its one of these just 20psi version...

https://www.amazon.co.uk/Shurflo-2095-2 ... B00NU5IRN4

This is the sort of thing I was thinking could be used...

https://www.tlc-direct.co.uk/Products/S ... l4QAvD_BwE

Your second link does not work. But as I said previously, so long as it can supply MORE current (4.5A in your case) and it is 12v dc it will be fine.

That looks like a modern day SU petrol pump, it will likely have a large back EMF not sure if it will damage a lighting power supply, personally I would test on a battery first, and would consider using a small battery and battery charger rather than a power supply.

Mr White wrote:Your second link does not work. But as I said previously, so long as it can supply MORE current (4.5A in your case) and it is 12v dc it will be fine.

tks for help yea this one runs to 60 watts.. nothing ventured I guess! If it doesnt work then I can default to the battery.