Led lamp not working

[fudd]

I bought a new 12v led lamp for my shower room. I wired it up and unsurprisingly!!! it didn't work. Is there a way I can test it? I don't want to send it all the way back to China. Theyve got enough rubbish over there already

[Guest]

Afraid I have had ones from China that were dodgy (and some that were OK.)

Have you definitely got the polarity right?

Edited November 23, 2015 by Guest

[lesanne]

Have a quick look and make sure the pos and neg are connected the right way round, that might be the problem

Nice one catweasel. same idea posted at the same time

[fudd]

I can't see any difference in the cables. Both white and the same markings.

[cuthound]

I can't see any difference in the cables. Both white and the same markings.

Then try swapping them over. After all you have nothing to lose.

[fudd]

Then try swapping them over. After all you have nothing to lose.

I've done that. Nothing.

It was cheap. I'm not bothered about it really it's just the hassle I don't want.

Thanks

[lesanne]

Not being funny, have you checked there are 12v in your existing wiring to power the light. Stick a multimeter on the supply to test it.

 

Sounds daft, but is the switch turned to on? ( it happens to the best of us!)

[Guest]

Do you have a voltmeter, and can you measure the voltage at the fitting? If you are not getting close to 12V (assume 12V boat) the LED may not light.

It is definitely a 12V LED and not a rogue 240V one got in there? Having read some Chinese ads on Ebay there is some confusion over voltage of LED's!

 

You beat me this time Lesanne

 

Also the switch is a good point: it seems a slightly corroded switch contact may not pass the tiny current required for an LED. You could test the lamp across a 12V battery.

Edited November 23, 2015 by Guest

[fudd]

I've checked the connections. Both clean. I think it got crushed in transit. There's damage to the packaging. I might try it on 240. Just to see. At least I'll know what voltage it is. I'll stand well back.

[lesanne]

Just a thought, if it is a duff one, rather than send it bike, its worth sending a message to the ebay seller and letting them know. In my experience they will more often than not just send you a replacement if the item wasn't very expensive. They prefer to do that than receive any negative feedback.

[Loafer]

It COULD have a light sensor in it, that turns itself off if it's daylight.

 

Did you test it in daylight? Try it in the dark.

 

I returned one to Midland Chandlers - they just sniggered and gave me the proper one without an auto switch-off!

[craftycarper]

Another reason to support your local shop, A it would not of got damaged in transit,B you could just take it back and C was it really worth saving a couple of shillings, for the hassle you now have, we will all be moaning when there is nowhere left to just pop in and grab what you want, sorry I,ll put me soap box away

Edited November 23, 2015 by craftycarper

[fudd]

I've done that but had no reply. I'll leave it at that rather than leave negative feedback. They may reply and it will be too late. I'd rather leave no feedback.

[ditchcrawler]

I have been told that if you paid by Paypall thats the way to go. They just take the money back first and then start discussing things.

[jake_crew]

I might try it on 240. Just to see. At least I'll know what voltage it is. I'll stand well back.

I really wouldn't try it on 240v,

 

If it doesn't work at the specified voltage, 20x more isn't going to fix it

[Guest]

I've checked the connections. Both clean. I think it got crushed in transit. There's damage to the packaging. I might try it on 240. Just to see. At least I'll know what voltage it is. I'll stand well back.

I would test it across a known 12V supply before I went bunging 240V through it! Are you definitely getting 12V with it in situ?

[ditchcrawler]

Again I would say tell us what you have bought, post a link, the answer may be there.

[Flyboy]

Afraid I have had ones from China that were dodgy (and some that were OK.)

Have you definitely got the polarity right?

I think you will find that most LED's come from China, even the branded ones.

[Guest]

I think you will find that most LED's come from China, even the branded ones.

 

Yes, the ones I get from Asda are made in China; the ones I bought on Ebay came directly from China. The ones from Asda are infinitely more reliable, with all the "Ebay" ones having failed. The good news is I was able to convert them to 12V for the boat, since the internal transformer circuit had failed in every case.

I assume the ones produced for Asda and suchlike go through a better quality control regime.

[Phil Ambrose]

Bedazzled may be more expensive but they do work. Voltage from 10v to 30v and have an internal fuse. Have used them throughout my boat.

Phil

[fudd]

Again I would say tell us what you have bought, post a link, the answer may be there.

I've looked at it in daylight and it says 240 in 12-24 out in tiny embossed printing. I've cut the guts out and wired it into the 12v still doesn't work. I'm going to bin it. My fault really, I thought I'd read the info. I don't remember it saying 240v but you pays yer money I suppose.

Cheers.

[craftycarper]

I've looked at it in daylight and it says 240 in 12-24 out in tiny embossed printing. I've cut the guts out and wired it into the 12v still doesn't work. I'm going to bin it. My fault really, I thought I'd read the info. I don't remember it saying 240v but you pays yer money I suppose.

Cheers.

. I think you have bought one designed for fitting in a house, as they are all 240 but have a transformer hidden in the ceiling that converts the current down to 12v, i buy most of my led from a motor supplier as its all designed to run straight off the 12 volt system

[fudd]

. I think you have bought one designed for fitting in a house, as they are all 240 but have a transformer hidden in the ceiling that converts the current down to 12v, i buy most of my led from a motor supplier as its all designed to run straight off the 12 volt system

No I didn't. It was described as 12-24 volt.

I'm going to smash it to bits later.