MR16 LED problem!

gazzamikes · Jun 28, 2011

This may be me just having a bad day but installed 12 MR16 24V downlights, customer requested led, ordered them from toolstation as it was literally two second walk. all connected and fitted etc, big switch on and all i got was a little flash from some and nothing from others! made a test set up and tried with and without transformer, contacted manf they reckon they should work and that they maybe dodgy batch... all 12? any ideas guys? probably such a simple answer but today brain doesnt want to function! thanks!!

telectrix · Jun 28, 2011

surely they.re 12volt and LED lamps require the correct trannies/drivers. you will probably need to replace all the trannies

gazzamikes · Jun 28, 2011

sorry yes 12v not 24v

according to manf they dont need require led drivers, surely they would?

telectrix · Jun 28, 2011

but they do need a tranny suitable for LED. not sure what they are called, constant current or constant voltage or someting. some trannies require a minimum load or they shut down. haqve you measured the volts at the lamps when switched on?

sjhall · Jun 28, 2011

what make are they ? sounds like they need LED drivers

gazzamikes · Jun 28, 2011

reading at 12.14V thats the impression i was under, a constant driver of the required current

telectrix · Jun 28, 2011

i'd take a tranny and a led fitting to the wholesaler . fit a 13A plug and get them to plug it in.

gazzamikes · Jun 28, 2011

they are called L.E.D ultimate so not a well knwon make, my first though was poor make

gazzamikes · Jun 28, 2011

thats good idea ill nip it tomorrow, just a pain isnt it when near the end and things go wrong

johnthesparky · Jun 28, 2011

you get constant current and constant voltage, and I have fitted a current driver as specified to a firstlight fitting that just pulsed, ended up going back with a firstlight driver and it worked fine, even though the specs were the same for both drivers....

sounds to me like its a driver problem, is there a recommended driver for the fittings?

gazzamikes · Jun 28, 2011

they were unable to recommend one, they had one at £24.97 but didnt have any in stock, are we talking one per fitting as with trannys? because in this case it makes one expensive job!

Dunc · Jun 28, 2011

Did you wire it so there was a transformer per lamp or did you run multiple lamps of a single transformer? If it's the latter it generally won't work as the transformers don't like it. Quick fix is replace the transformer for a 12V LED driver. If it's the first scenario then the lamps and transformers may not be compatible. Again replace the transformers for drivers and all will be well.