another led vs halogen question

eyeofthetiger999

Hi everyone. I have had led GU10 bulbs for my bathroom and kitchen for 4 years with mixed results. I bought approx 20 and I reckon about 10 of them have failed in that time. I have a living room with 6 50w MR16 bulbs. I have done the maths and I calculate I am spending approx £18 a year just to light up this room for 2-3 hours a day! I recently bought some MR16 led 3w bulbs on ebay for a good price. Unfortunately there were 3 problems:
1) They were too dim
2) One of them flickered
3) There was a buzzing sound
I have returned the led bulbs and swapped to 35w halogens which has probably reduced yearly cost to approx £12 a year.

I have been given varying advice that MR16 led bulbs cannot directly replace halogen bulbs as a transformer is required. I am not an electrician but if I have to employ an electrician for any adjustments it would certainly not be worth the switch. I would like to switch to LEDs if possible so wondered if someone could advice me if you think it is worth switching to LEDS and if so are alterations to the transformer required?

Thanks

rogerblack

I've actually designed and built my own LED lights.
This is not a practical route of assuring quality for most.
In general, I would advise do not purchasing cheap LED lights on ebay, as there are real quality and product description issues.
These may not even directly be the fault of the seller, who are simply copying the inaccurate product description given to them by the chinese vendor.

The main problem with MR16 replacements is not voltage - but heat dissipation - this means a premium is placed on quality - the bulb has to be high quality and produce a lot of light per watt so it doesn't overheat.

(for a given amount of watts out).

Purchase only brand names - I'd recommend Cree and Philips at this time.
https://www.earthled.com/collections/mr16-led-light-bulbs/products/cree-truewhite-series-mr16-mr16-50w for example.

This is a 12V bulb.
12V halogens are more common.
Do your bulbs have pins, or do the connectors look like ~5mm cylinders.
If they have pins, they are 12V, and you already have the transformer - LED bulbs are available for both.

If you choose not to go with a brand name - at the very least find one from a vendor in the UK that you can return to, and check for lots of good reviews!

http://www.amazon.co.uk/Bulbs-Halogen-Equivalent-3000K-White/dp/B00LN0RPA4/ref=sr_1_4?ie=UTF8&qid=1431256445&sr=8-4&keywords=mr16+50w+led for example seems to have good reviews.
These will not have quite the same output as a conventional halogen.
Perhaps 70%.
This is a 240V one.

Linton

Another point to note is that 12V transformers for halogen lights are different to those for LED lights - the light types are not interchangeable. I think that halogen transformers get upset at the low current draw for LED lights. Was the OP using 240V or 12V lights?

Dave_Fowler

Linton wrote: »

Another point to note is that 12V transformers for halogen lights are different to those for LED lights - the light types are not interchangeable. I think that halogen transformers get upset at the low current draw for LED lights. Was the OP using 240V or 12V lights?

I agree entirely. The lightweight rectangular transformers which are often used for 12V MR16 halogen bulbs usually have a minimum load requirement of around 20W. I have 6 ceiling mounted down-lighters in the kitchen. When I used 5W LED lamps to replace the 50W halogen lamps I found that the fm radio in the kitchen ceased to work because of interference and also after two or three days the lamps failed (initially flickering then they went out).

As an experiment I replaced the 12V transformer on one of the lamps with a 'real' wirewound toroidal transformer and the problem went away. However the cost of the transformer was too much to justify changing all the lamps and their associated transformers.

I found that I could get GU10 240V fittings which were an exact size replacement for the 12V fittings for less than the cost of the toroidal transformers. I removed the halogen lamp transformer at each light placement and replaced the old 12V fittings with the new GU10 fittings.

Dave F

almillar

Halogen transformers MAY NOT work with LEDs. They're expecting a big pull (20-50W) from the halogens, and mightn't notice an LED trying to take around 5W. Either the LED won't work, or it might flicker. Or it might work perfectly.
If you're changing from halogens with transformers, it's probably worthwhile doing the extra now and switching to AC (GU10 as above) fittings for better choice and easier replacement in the future.