MR11 leds flickering

[manx1641]

Hi, i've just replaced some mr11 gu4 halogens with led lamps, they all work but ocassionally they flicker, there are 2 12v 105w transformers each with 5 lamps, only 1 set will flicker at any time so i'm ruling out a mains fault,

has anyone experienced anything similar? are there specific transformers that work better with leds?

 

[Gary D]

Is there a dimmer involved?

Regards, Gary D
ResetTraining.co.uk

 

[manx1641]

No, theres no dimmer just switched from a single mk switch.

i've put a couple of halogens back in on each transformer and thats stopped any flickering from the leds,

so i now have 2 halogens and 3 leds on each transformer.

 

[roukel01]

The LED lamp probably doesn't like the transformer. For best results and to double the life of the LED lamp, you should use an LED Driver/Transformer.

LED Driver/Transformer 240V to 12V 10VA - LED Drivers - LED & accessories — (UK) Light bulbs, halogen lamps, spot lights and tubes by mail order in the UK

 

[Gary D]

What wattage are the LEDs retrofit lamps?
Is the flicker fast or slow?
And did both sets of 5 do it?

Regards, Gary D
ResetTraining.co.uk

 

[manx1641]

I cant remember what the wattage is and theres no markings on them other than 12v, they are the 15led type not the large 1.2w type,

all 5 would flicker at the same time, at first i thought it might just be a bad connectioon to a lamp so i've checked them all,

it's a fast faint shimmer like a flourecent tube with a bad ballast,

i'm thinking it's an under wattage situation as they seem fine now that i've fiited a couple of halogens,

i'll look in to those led drivers, thanks,

 

[gaffer]

Its the transformer,had this before in my Dads bathroom.He changed Gu10 lamps for LED and they used to flicker even when they were off!.Disconnected the trannie for the mirror heater and they worked ok.Had to put in a new cct for the mirror.

 

[bugsy]

As previuosley posted can't run led's on t/h trannies, should be either constant voltage or constant current drivers, and you will need dmx gear to dim them ( rako )

 

[Phil]

once fitted some lights in a night club expensive round things above the bar £200 each and he wanted 10 of them? more money than sense but who am i to argue any way i asked for the constant led transformer to go with them, the t*at on the counter gave me the wrong one ie just a normal 12 volt one it did my f****** head in trying to work out why they would not work. 30 minutes later while i am cleaning my crap up i looked at the trannie box, one short phone call ensured 15 minutes later there was the driver with the right ones

 

[MalcolmC]

I have just installed 4. 240v. 6W. GU10 LEDs
Three that are independently switched work fine. (single pole active switching).
However, the one that is two-way switched (switched from 2 locations) flashes (every 40
seconds) when turned OFF.
There are no dimmers in the circuits.
Any ideas on this one please?

 

[davelerave]

yes i've heard of this issue

can't recall at the moment the exact cause

think it's related to the strappers

 

[MalcolmC]

I think it must be a small amount of induced voltage that is obviously charging a capacitor by the regular firing.
Somehow it will have to be bled away.
I might just change the switches, although they megger out ok.

 

[malcolmsanford]

Have you a CPC in the circuit. If you haven't then that is the problem. If there is a CPC check if it is connected,

Because an LED is rated so low, some as little as 1v any capacitance in a circuit will build up and the LED will flash and discharge it. If you have a CPC connected it should discharge that way, check the Earth.

If the CPC is connected ok, then you may have to fit what is called a "snubber" to the circuit

 

[darrens1973]

I have just installed 4. 240v. 6W. GU10 LEDs
Three that are independently switched work fine. (single pole active switching).
However, the one that is two-way switched (switched from 2 locations) flashes (every 40
seconds) when turned OFF.
There are no dimmers in the circuits.
Any ideas on this one please?

You need double pole switches, unfortunately when 2 way is involved there is not really any answer I am afraid.
There are new issues with LED retrofit lamps coming out every day. what a nightmare !!!

 

[topquark]

You need double pole switches, unfortunately when 2 way is involved there is not really any answer I am afraid.
There are new issues with LED retrofit lamps coming out every day. what a nightmare !!!

That post is over a year old mate, think it'll be sorted by now

 

[darrens1973]

it was more for future info for anyone else, the more info thats on here the better

 

[malcolmsanford]

Darren how would you do this ? Most domestic situations a 3 plate lighting system is normally taken via the ceiling rose so where would you put this double pole switch? and why?

Also how will switching off 2 poles stop capacitance build up in the circuit ? While the light is on it's building up this, and even double poling the switch to isolate I assume you mean the LIVES, the capacitance will still have built up.

 

[shocking_eg]

i never have problems with proper dedicated LED fittings (AKA Halers)

retro fit lamps often fail and play up after a while. easier to change fittings to dedicated ones (then you get the nice long warranty with them lol)

 

[grandfortune]

get MEGAMAN LED's , this seems to solve the problem of flickering lamps, i think the dimmer ones are comming out in september

thanks
Grand