downlights problems: dimmer, transformer or wiring?

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In my hallway I have 5 spotlights controlled by touch dimmer switch on the one side and a normal on/off switch on the other side of the hallway. Before I had 5 x 50w, MR16, 12V halogen lights, then replaced with good quality Philips LEDs.

I never manage to control the dimmer, sometimes it will go on or off by itself or when switching the lights in the nearby rooms. Also, most of the times the halogen bulbs will stay on with a dimmed light output. When recently replaced one of the bulbs, I could see that was in contact with the transformer and the outer box of the transformer was burned a bit.

What could be the problem, the dimmer switch, the possibly damaged transformer or can be a general wiring problem?
 
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Also, most of the times the halogen bulbs will stay on with a dimmed light output.
You said you've replaced them with LEDs.


When recently replaced one of the bulbs, I could see that was in contact with the transformer and the outer box of the transformer was burned a bit.
Not good.

Define "a bit".

What could be the problem, the dimmer switch, the possibly damaged transformer or can be a general wiring problem?
Now you have LEDs, are you meeting the minimum load requirements of the dimmer and the transformer?

What happens if you replace the dimmer with a switch?
 
Also, most of the times the halogen bulbs will stay on with a dimmed light output.
You said you've replaced them with LEDs.


When recently replaced one of the bulbs, I could see that was in contact with the transformer and the outer box of the transformer was burned a bit.
Not good.

Define "a bit".

What could be the problem, the dimmer switch, the possibly damaged transformer or can be a general wiring problem?
Now you have LEDs, are you meeting the minimum load requirements of the dimmer and the transformer?

What happens if you replace the dimmer with a switch?

Before replacing the halogen with led most of the times after switching off the lights I could see a dimmed light on the bulbs.
The transformer plastic box is melted, in the place that was in contact with the halogen bulb there is a hole and I can see the metal casing inside.
I did not try to see if a normal switch will work OK.
 
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So did you replace the transformers for drivers when you replaced halogen for LED?
Did you purchase dimmable LEDs?

I did not replace the transformers with led drivers since I read that Philips Master LEDs will work with most transformers. Yes the bulbs are dimmable.
 
So the transformers are dimmable as well and you have exceeded the minimum load per transformer but not exceeded the maximum load?
The other issue would be that there seems to a problem regarding the configuration, if other parts of the circuit are effected, is either switch two gang switch?
 
So the transformers are dimmable as well and you have exceeded the minimum load per transformer but not exceeded the maximum load?
The other issue would be that there seems to a problem regarding the configuration, if other parts of the circuit are effected, is either switch two gang switch?

Regarding the transformers, they should be dimmable since before with the halogens but also now with the LEDs I can use the dimmer, with problems though. I have also seen somewhere that the bulb should be considered by its Halogen Equivalent Wattage not its Rated Wattage. In this case the 7w LEDs are equivalent to 35w halogen so should be OK.

Now the configuration seems most likely to be a problem. Sine there are two switches on each side of the hallway it seems that originally it was meant to switch on/off the lights from both sides of the hallway. With my basic understanding, for this should use two normal switches, 1 gang, 2 way each. Could it be the problem, how can I fix it?
 
I suspect you're not meeting the minimum load for the dimmer, I had 4x11W Master LED's with a touch dimmer and it was just crazy bad.

5 x 7 = 35w, your minimum load is probably 40/50w

Try it with a normal switch and see if everything behaves then take it from there
 
QUOTE: I have also seen somewhere that the bulb should be considered by its Halogen Equivalent Wattage not its Rated Wattage. In this case the 7w LEDs are equivalent to 35w halogen so should be OK. QUOTE.


Either you mis read that or it was written by an idiot.
 
This is actually true for Philips LED lamps, they work perfectly on a ~50va tranny even though they're only 7-11w

I've got 4x3w 12v fed from one 50-105va tranny and they work fine
 
This is actually true for Philips LED lamps, they work perfectly on a ~50va tranny even though they're only 7-11w

I've got 4x3w 12v fed from one 50-105va tranny and they work fine

No it is not.

4 3W LEDs takes a total of 12 watts. Not knowing their power factor I don't know the VA load but I doubt if it is as much as 50VA.

Are you using a transformer as you say or a switch mode power supply? I suspect the latter as transformers don't usually have a minimum load. Just because they appear to be working don't be surprised if the switch mode power supply has a short life due to wrong loading.
 
Philips LEDs work with 99% of, if we're being accurate, SMPS on the market and they were specifically designed that way, and I dare say a lot of other LEDs do not, but Philips do. Go have a read of their literature.

I have seen literally hundreds fed from singular SMPSs for the best part of 3/4 years with no failures of lamp or SMPS
 

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