240v to 12 v

[chrishelen]

What is the best way to achieve this please, I have an open boat and the cover is away for repair,but I have mains electricity and I want to run the 12 volt bilge pump off this, I need to be away for a week, and we have heavy rain for the week.

 

[davidpbo]

Readily available 240V ac to 12Vdc power supply of appropriate current rating for whatever you need to run in a sutably weather proof container.

Aldi have these coming in. CPC, B&Q etc. will have similar.

Weatherproof Outdoor Power Kit from 16.11.2014 at ALDI: https://aldi.in/5wle

That gives you a timer if necessary, an earth leakage (Residual Current Device) to plug into the socket feeding the extension cable if necessary (Must be in a dry location) and a weathproof box to put the 240/12v psu in.

N.B. You would have to buy the power supply separately.

I have used similar boxes for powering christmas tree lights and found them to be waterproof for months if sensibly placed.

You may be able to fettle other plastic containers to suit, I have used plastic biscuit boxes. But imho the dedicated boxes are good because the ones I have have a soft rubber in the cable entries which seal them against rain but not standing water.

 

[chrishelen]

Just the job, thank you.

 

[sarabande]

..

 

[chrishelen]

Hi Sarabande,
I have an open boat, I use it everyday for work, all the rainwater and any sterngland leaks go straight into the bilge, I don't want the auto bilge pump to drain the batt if we have heavy rain as forecast, I have 240 v available. I need to be away from the boat for a week and don't want it to sink.

 

[fireball]

I have a 240v to 12v unit - it's not waterproof - but it could be placed in a container. We bought it to run our coldbox a few boats ago and not used it much since - hadn't thought about it, but I'm quite happy to sell it on for £10 - based in Chichester if that's of any help.

It's like this:
http://www.outdoorgear.co.uk/Campin...cMM6eqxp8ibFqvMTB9h6dMf4_Forw2GBkQhoC8mvw_wcB

 

[chrishelen]

Hi thanks, I had a word with the livaboard in the next berth to me this morning, he seems OK I think I can trust him to run the bilge pump if we get significant rain which is for cast for the weekend.
Just one question, would I connected the transformer to the boat batts via the cigar socket?

 

[Tranona]

Another possibility is to install a battery charger to top the battery up - or even a solar panel. The drain from the pump will not be huge if it pumps out any water as soon as it gets in.

 

[fireball]

The unit I've got is a totally independent 240v->12v transformer - it should be completely separate from a boat/van 12v supply. We've used it when camping to run the coolbox or on the previous boats that didn't have a battery charger for the same.

You connect it to the mains and it provides 12v in a cigar socket.

You could equally install a battery charger - providing it's smart enough to provide a float charge once your battery is full then it won't harm it.

 

[LadyInBed]

Just one question, would I connected the transformer to the boat batts via the cigar socket?

You could, but it would be a weak connection, prone to being intermittent and restricted current, 3-5 amps.
The best solution is croc clips from the charger across the battery.