12 Volt Replacement LED Bulbs

[Captn D]

Having recently purchased replacement 12v G4 LED Bulbs for a very reasonable sum of £8.99 for 10 from Amazon, having been advised they were good for voltage variations up to 15v, and found that 4 out of the 6 replaced failed when the battery charger was in boost mode with an output of 14.3v. These bulbs were similar in shape to the G4 Halogen replaced being just a little larger. I understand that one can purchase disc shaped G4 LED replacements that have voltage tolerant circuitry and are rated at 10v - 30v, but cost around £4.90 each! Since, I have around 16 halogen to replace, I consider £80 probably not worth it. Does any forumite know of a reasonably priced 12v LED that is suitably tolerant to voltages up to around 15 - 16v?

 

[jwilson]

I bought similarly cheap warm white LED bulbs from China via Ebay last winter: every one worked and so far none have gone wrong. My voltage goes up to about 14.4 at max charge and no load.

 

[RichardS]

Having recently purchased replacement 12v G4 LED Bulbs for a very reasonable sum of £8.99 for 10 from Amazon, having been advised they were good for voltage variations up to 15v, and found that 4 out of the 6 replaced failed when the battery charger was in boost mode with an output of 14.3v. These bulbs were similar in shape to the G4 Halogen replaced being just a little larger. I understand that one can purchase disc shaped G4 LED replacements that have voltage tolerant circuitry and are rated at 10v - 30v, but cost around £4.90 each! Since, I have around 16 halogen to replace, I consider £80 probably not worth it. Does any forumite know of a reasonably priced 12v LED that is suitably tolerant to voltages up to around 15 - 16v?

I must admit to buying 13 of the voltage protected flat G4 replacements which use 10 of the newer 2835 LEDs from boatlamps at £8 odd. These are expensive but they are fantastic bulbs which are the same warm colour temperature of the original G4s but each one is so much brighter than the G4s that the difference in the saloon is quite startling. We now use about 10% of the power and can light up the salon like a football stadium if we want to.

Richard

 

[nigelmercier]

I've just bought a load of these from Banggood

 

[RichardS]

I've just bought a load of these from Banggood

They look like very good value but seem to use twice as much power as the boatlamps ones and specify 12V rather than 10-30V which the voltage stabilised ones specify. Have you tried then yet because they might well have a fairly short life when the batteries are on charge.

Richard

 

[GHA]

Having recently purchased replacement 12v G4 LED Bulbs for a very reasonable sum of £8.99 for 10 from Amazon, having been advised they were good for voltage variations up to 15v, and found that 4 out of the 6 replaced failed when the battery charger was in boost mode with an output of 14.3v. These bulbs were similar in shape to the G4 Halogen replaced being just a little larger. I understand that one can purchase disc shaped G4 LED replacements that have voltage tolerant circuitry and are rated at 10v - 30v, but cost around £4.90 each! Since, I have around 16 halogen to replace, I consider £80 probably not worth it. Does any forumite know of a reasonably priced 12v LED that is suitably tolerant to voltages up to around 15 - 16v?

Doubt if you'll find decent leds with a constant current power supply built in for pennies. Another option might be putting in a voltage regulator in the circuit to stop the volts going too high. Loads of eBay, search for lm2596 buck. Downside is you'll loose some voltage on the way but might not be that obvious.

 

[nigelmercier]

They look like very good value but seem to use twice as much power as the boatlamps ones and specify 12V rather than 10-30V which the voltage stabilised ones specify. Have you tried then yet because they might well have a fairly short life when the batteries are on charge.

They are 20W equivalent, very bright. Yes, Banggood say they are for 12V, but if you look at the pictures you will see that they have a significant number of active components to stabilise the current. I've had a couple on for about 20 hours, under charge at over 14V. If I get time before I go out again I'll test one at a higher voltage for a while.

 

[William_H]

OPs best bet is to use what he has but fit a ressitor in series with each one to further limit the current. the resitro will reduce the light a little so some experiment will be needed. If the ligts are 3 w then .25 amp current then you need to drop 2 volts so R+E/I so 8 ohms should make them safe.
This value ould be made 4 ohms for 2 lights in a circuit. or 2 ohms for 4 lights. The resitor for one lamp will dissipate .5 watt so need to be capble of dissipating 1w and for multiple lights ojne resitor you need a 5w capable resitor which will get warm.
If you find the loss of light too much then you couild fit a switch to bypass the resistor when running on batteries not on charge.
From there there are more options for auto current limiting ie using a buck/boost regulator. (from China.) good lcuk olewill

 

[Plevier]

I've just bought a load of these from Banggood

I had some very like those, maybe identical, from a different ebay vendor.
I put them in some small glass fronted downlighters in place of 10W halogens. To my surprise they overheated to the point where LEDs unsoldered themselves and fell off (self limiting the overheating!) I still can't understand why this happened. My charger never goes above 14.4V.

In one case I broke the cover glass and had to leave it out; that one has not overheated.

Nigel's link also shows some "bulbs" where the LEDs are potted in a clear cylinder shape a bit bigger than the original halogen bulb. I have found these excellent in wall lights.

 

[Steve Clayton]

Ledhut

 

[RichardS]

They are 20W equivalent, very bright.

Good grief, that is bright! My 1.6W ones are much brighter than the 10w G4 originals such the the saloon and cockpit are actually much nicer places to sit and read at night. I know that vision is not linear but if yours are twice as bright as mine you will be able to turn half the lights off!

Richard

 

[nigelmercier]

I've had one being driven at 15V for 12 hours now. It's quite hot to the touch, but otherwise happy. I'll do some more tests tomorrow.

 

[nigelmercier]

I've just bought a load of these from Banggood

I've had one being driven at 15V for 12 hours now. It's quite hot to the touch, but otherwise happy. I'll do some more tests tomorrow.

OK, more tests done. The attached show the relative LUX readings for different voltages, note the cut-off at around 11V-12V:

I also ran it for about 10 minutes at 30V (159600 LUX). No significant heat increase, and still working.

 

[GHA]

Lovely data how did you measure the lux?

And what's the code on the chip with with 5 terminals bottom centre? Top one is a bridge rectifier, so might run on ac as well, can't see the code on the back of the bottom one in the pic.

 

[nigelmercier]

Lovely data how did you measure the lux?
And what's the code on the chip with with 5 terminals bottom centre? ...

Measured with a Digital Lux Meter, also from Banggood. Sensor was 25mm away from lamp.

The 5-pin chip says 4211

 

[maxi77]

I must admit I use cheap ebay units and even after 6 months on with shore supply I have had no failures.

 

[temptress]

Having recently purchased replacement 12v G4 LED Bulbs for a very reasonable sum of £8.99 for 10 from Amazon, having been advised they were good for voltage variations up to 15v, and found that 4 out of the 6 replaced failed when the battery charger was in boost mode with an output of 14.3v. These bulbs were similar in shape to the G4 Halogen replaced being just a little larger. I understand that one can purchase disc shaped G4 LED replacements that have voltage tolerant circuitry and are rated at 10v - 30v, but cost around £4.90 each! Since, I have around 16 halogen to replace, I consider £80 probably not worth it. Does any forumite know of a reasonably priced 12v LED that is suitably tolerant to voltages up to around 15 - 16v?

I replaced all the 12v bulbs on Temptress with LEDs supplied by SEAROLF . We live on-board and are very pleased no problems with voltage.

 

[Plevier]

I've had one being driven at 15V for 12 hours now. It's quite hot to the touch, but otherwise happy. I'll do some more tests tomorrow.

Nigel, I guess your very interesting tests are being done with free air around the units?
Will you be fitting them into enclosed downlighters?
Bearing in mind my overheating experience reported above, are you going to do any testing in a (simulated) installed environment?
Mike

 

[JumbleDuck]

OPs best bet is to use what he has but fit a ressitor in series with each one to further limit the current. the resitro will reduce the light a little so some experiment will be needed.

It is not generally a good idea to use a passive linear device like a resistor to regulate a non-linear device like an LED. It's OK when you have a constant supply voltage, but when it's varying all over the place the regulation will almost always be wrong. Proper regulated bulbs are cheap.

 

[GHA]

The 5-pin chip says 4211

Brings up a load of LED drivers on google. With the bridge rectifier it might even work on the mains. I'd be standing well back before trying that out though..