Led from Ikea

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ronmarson

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Gentlemen.
Help please.
I have a wonderfully slim LED that cost €15 in Ikea, and came with what I thought was a transformer.
The 'transformer' is marked:
220-240v 50/60Hz 0.07A.
12VDC. Max 0.5A. 0.5-6W.
I now see the 'transformer' in marked LED Driver

I cut the plug off and connected the light to a 12V motorcycle battery in the shed and it works grand. It has 18 LEDs in a slim tube a foot long and probably half an inch diameter.
Before I drive to Dublin and spend out on another four of these I wonder if they have a long life expectancy without some complicated electricery.
All replies welcome, if they are written in simple English.
Capt. RoN
 
Because your 12V system is charging the battery at perhaps 14V, the leds may be driven harder than they were designed for.
That may shorten their life.
Or make no difference.
In the limit. if you have a smart charging system, it could be 15V, so it might be significantly more current.
But it still might be fine, the product will be designed to cope with at least Californian temperatures.
A lot of people are using similar things with no issues, but from a technical point of view, I'd know why if they did blow up.....

You can add a regulator to keep it down to 12V, or stick a resistor in series to drop the excess volts.

Some LEDs have current control modules which prevent the problem for any reasonable range on input volts.
Many are just a series resistor for every 3 LEDs though.
 
I've got a number of Ikea LED strips in the boat, all running of the battery. They've been fitted for about four years now and get daily use through the year. No problems with them whatsoever. When the boat is away from shore power, I'm lucky to get above 14 volts with the engine running. Alongside, the voltage usually peaks at about 14.3 volts. Neither of these voltages have proved to give any problems with the LEDs, nor with any of the other LEDs I have fitted.
 
ronmarson said:
... It has 18 LEDs in a slim tube a foot long and probably half an inch diameter...
Click to expand...

As others have said, it will probably be OK. Why not measure the actual output voltage of the LED driver to see what it expects.

It sounds like the tube could be a candidate for fluorescent tube replacement, do you have a link, or the (daft) name?
 
I was skippering a charter boat and very early on the last morning, as I helmed the boat under engine, the crew had the saloon lights on whilst they packed their things.
I can't describe the feeling that came over me about an hour into the trip when one poked his head up into the cockpit and shouted 'FIRE'!

It turned out to be an LED that was being supplied with too many volts from the alternator, had got very hot and was burning the surrounding laminate - so my advice would be to fit a regulator unless you too would like to experience that instant blood draining, paralysing fear.
 
12V becoming 14/15V isn't a big deal, there will be a slight increase in LED brightness, what can kill them is spikes from starters and alternators. Properly constructed LED lights will have a suppressor fitted.
 
savageseadog said:
12V becoming 14/15V isn't a big deal, there will be a slight increase in LED brightness, what can kill them is spikes from starters and alternators. Properly constructed LED lights will have a suppressor fitted.
Click to expand...

LED s don't suffer from reasonable spikes of voltage. (short duration) what kills LEDs is the average power hence temperature of the junction. So suppressors as such are not needed unless spikes are of very high voltage..
Now the LED driver supplied by Ikea may be a 12v supply "transformer" but also my be a current limited LED supply which may in fact supply power in spikes of voltage and current.
OP s test on a motor bike battery saying it looked grand may infact indicate that the LEDs are getting too much power and getting too hot.
He should check the current being drawn from the motor bike battery. You should draw no more than the rating of the fitting form the motor bike battery. If is 6watt fitting then 1/2 amp from the battery. Any more will be a cause of alarm. This will give short LED life and possible fire. If it does draw too much current the fix is to fit a resistor in series with the 12v supply. Again as an example of 6w fitting a 2 ohm resistor will drop 1 volt and should reduce the current by a useful amount. This resistor will then waste .5 watt so get a 5 watt max rated resistor. If the fitting rating is more than 6w then the same resistor will reduce current volts even more. If you find you run the lights on a shore charger or with engine running you might be safer to reduce the current even more for a slight drop in brightness. Buy a handfull (they are cheap) of 2 ohm or 1 ohm wire wound resistors or even 3.3 ohm or 4.7 ohm. Fit them in parallel (halves ther resistance) or series doubles the resistance set a suitable current drain and brightness. Even fit switch for dimming.
good luck olewill
 
Most of the led's I've seen fitted to cars seem to flash rapidly as can be verified by glancing across them - you see dashes of light rather than the continuous trail of incandescent bulbs. So that would suggest a switching circuit rather than a continuous voltage
 
savageseadog said:
12V becoming 14/15V isn't a big deal, there will be a slight increase in LED brightness, what can kill them is spikes from starters and alternators. Properly constructed LED lights will have a suppressor fitted.
Click to expand...

Certainly some truth in that, provided the original design at 12V is conservative enough. Probably life will shorten from 'longer than anyone cares about' to 'longer than I'll keep this boat'?
Starter motors can put interesting spikes on the '12v'.
I don't think most LED set ups have much in the way of suppression, but problems seem to be rare in actual use?

Most yachts, the leds are running off the house battery, so a bit of isolation from the starter.
 
lw395 said:
Certainly some truth in that, provided the original design at 12V is conservative enough. Probably life will shorten from 'longer than anyone cares about' to 'longer than I'll keep this boat'?
Starter motors can put interesting spikes on the '12v'.
I don't think most LED set ups have much in the way of suppression, but problems seem to be rare in actual use?

Most yachts, the leds are running off the house battery, so a bit of isolation from the starter.
Click to expand...

I can assure you that the Labcraft units which are decent quality have suppressors. The type of suppressor used I'm not sure of. When I refer to damaging spikes I'm talking of reverse ones as well. Spikes are inherently high frequency and tend to propagate in ways that are difficult to comprehend.
 
I did the same with some Ikea flat LED lights about 7 years ago. They didn't last long, but what killed them, I don't know. I suspect damp. A strategic smudge of Vaseline may avert it.
 
Led's are semiconductor devices, much like transistors and integrated circuits. Running them directly off automotive/boat type power supplies ie, relays, high power alternators, big earth loops etc etc is asking for shortened life spans.

Sure they look and appear to work like simple light bulbs but they aren't. All of the advice to just chuck a resistor in series with them is adding to the confusion about LED's

If you want long lifespans and clean,radio interferance free operation that delivers the true available power savings of led lighting then you need a quality, stabilised and protected led lighting supply.
 
I've read these sort of threads many times, in some puzzlement. I live on board, so use lighting just about every day of the year. I fitted LEDs in all the light fittings plus I have 2 sets of Ikea LED strip lights, all running straight off the battery. The main light fittings have been in for four to five years, with the occasional partial failure (2 or 3 individual LEDs failing). They give good, pleasant light in exchange for about 20% of the current of halogen or incandescent. The Ikea strips are brilliant, great light mounted behind grab rails providing the extra light needed in the galley area. No special circuits, just a connection to the 12 volt system on the boat. I've no idea if I've just been lucky or what, but they're as cheap as chips and as a result I carry spare against the unlikely event of failures, just like I used to with halogen bulbs, which used to blow with monotonous regularity.

Now, someone will be along shortly to tell me why I'm wrong but that's my experience of the things.
 
Many thanks for all the advice, some of which I understood, some I didn't.
I think I will buy one of the things suggested by Hadenough and wire it into the feed from the Interior lights switch.
If it all goes wrong I will report. (If I am able)
Thanks again to all you experts.
Capt. RoN
 
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