January 26, 2014 / consort3

MR16 Led bulb problem

A friend recently tried to retrofit LED MR16 bulbs for the Halogens originally fitted in his relatively new shower down-lighters. However he just got a flash or nothing when the new bulbs were tried. This is a very common problem and is caused by the electronic transformer type supplies used to convert the 230Vac mains to 12V for the bulbs.

I could not find much on the net about this but eventually found this article which explains the problem in engineering terms:

http://www.ledsmagazine.com/articles/print/volume-9/issue-2/features/low-voltage-led-lamps-present-unique-driver-challenge-magazine.html

Basically the LED bulbs demand so little current that the supply does not turn on. One way around this as described in the article is to wire 4 led bulbs in parallel to create enough load for the supply to turn on. The more correct way would be to use a Led driver supply.

More on the Halogen electronic transformers from Rod Elliot:

https://sound-au.com/lamps/elect-trans.html

I have started to modify existing lights to use GU10 230V ac bulbs and found this firm helpful:

http://www.s-lilley.co.uk/

The most be one of the oldest firms still going, being founded in 1840

Flourescent tubes are now being replaced by Led types. Cree have had to recall some

http://www.ledsmagazine.com/articles/print/volume-12/issue-6/features/indoor-lighting/philips-lighting-charts-independent-course-to-ssl-success.html

Good article on light bulb specifications

https://hackernoon.com/the-trinity-3-specs-you-must-know-when-purchasing-led-light-bulbs-46abb9a6398d

A friend had this early version of the British fused plug made by Dorman Smith (1955)

dormansmith