LED light power units

A battery charger isn't a 12V power supply. What's it for?

It looks quite cheap, but there's almost no techincal data. Searching the web, looks like it's spec'ed for 100mV ripple. Also, I don't see any indication it has power factor correction, which would mean it can't be used in products sold in the EU.

Slightly out-the-box answer, but is this going to be a constant requirement? Assuming it's not a fairly constant 24x7 10A demand, the rough-and-ready answer would be to connect the load to a car battery, which is itself hooked up to a

Thanks Andrew. It is not a commercial application and only sporadic use so I'm not concerned about PFC.

Thanks for the idea but the application is not really suitable to make a car battery an acceptable part of the set up.

It will be used to run car radiator type fans but for a completely different application. The dimmable function of some of the supplies could be useful as a speed control.

There are 10A+ car battery chargers out there - but they're not cheap, and they're mainly "intelligent" to prevent (entirely predictable...) over-charging. Which means you'd need to "show" them some kind of low voltage before they'll start putting +14v out - and, even then, they're likely to do something "clever" that's not really helpful for your application.

I wonder... 3 x 4A cheap-and-cheerful low-tech "dumb" battery chargers?

Might work but the price of the ebay units at £17 ish is possibly better than 3 small chargers and is starting to look like it could do the job. I've got some big old linear PSUs but this is for someone else and preferably they can just buy the ebay part , wire it up and the job's a good-un.

A PC psu will give 5v at way over 10A, which should run a car fan at a fair lick. If you need the full 12v at 10A, just use 2 or 3 together. Cheap as chips - well, cheaper.

NT

If you're willing to import from China, CCTV camera supplies in chassis mou nt format are about £15 on ebay

Owain

I Mr William Heath Robinson is alive and well by the sound of this thread, there again it is uk.d-i-y I suppose, but remember that Darwin had a point too.

It might be worth looking for a 12V server PSU on eBay. These have output ratings of many hundreds of watts and are often quite cheap. You might need to search around for the connections needed to switch on the output.

John

Very true - on both counts. The key is finding out the true performance/compromises when specifying one item for re-use in another application. These LED supply units do look quite benign for use as a basic power supply but I've experienced other 'electronic transformers' used for filament lighting and these are the work of the devil only being suitable for resistive loads and then only switching on when a certain load threshold is exceeded. Perfect for filament lamps but not a lot else. It is just not good enough for us experimenters when products design for one application can't be used for something else!! :-)

mm! that looks interesting. Thanks Owain