Dimmers and LEDS...!!!!

[Barnaby Stedman]

yesterday was working in a house where a different sparky had installed LED spotlights on dimmer switches. the leds flicker when you dim them. also the mcb the lights are on buzzes when the LEDs are on - to do with harmonics I think. But the funny thing is I know another house that was done by the same sparky with the exact same problems. Why would he keep doing that - surely he would have learnt?? and is it only certain combinations of dimmers and LEDs that flicker because I constantly install LEDs on dimmers but they never flicker?

 

[MJPD29]

Maybe he hasn't got a clue what he's doing

 

[Barnaby Stedman]

maybe... but what do you suggest he does to change it?? different dimmer switches?? i think he uses bg nexus ones - has anyone had any problems with them? is it to do with the wattage rating of the dimmer?

 

[Charlie_]

Compatibility issues..
Standard 240v LED fittings are best dimmed using trailing edge dimmers..
Don’t want to get too technical..
Zano and varilight are the most readily compatible
You should do some research, the manufacturers have compatibility charts.. Have a look at them, sorry tell your friend to have a look

 

[Charlie_]

If you try to use traditional type dimmers with LEDs you will overheat then and cause damage to them and associated equipment on the circuit

 

[DT1991]

+1 for Zano never had a issue with them fitted to various led loads.

I once fitted a BELL dimmer module did loads of research, on paper it was 100% compatible. 10 seconds it was in and it started to smoke and melted.

 

[Barnaby Stedman]

Compatibility issues..
Standard 240v LED fittings are best dimmed using trailing edge dimmers..
Don’t want to get too technical..
Zano and varilight are the most readily compatible
You should do some research, the manufacturers have compatibility charts.. Have a look at them, sorry tell your friend to have a look

yes i understand your point. i have noticed zano before. its all to do with the copper coil inside a traditional dimmer I think. will let him know

 

[DPG]

Let us know what he says.

 

[ElectricSeamus]

The OPs sarcasm radar seems to be on the blink too.

 

[Charlie_]

yes i understand your point. i have noticed zano before. its all to do with the copper coil inside a traditional dimmer I think. will let him know

The coil in traditional dimmers is there to absorb spikes caused by the triac switching on and off at the peak.
A triac is basically just an electronic on off switch..
Remember as a child when you would hold a switch till the light flickered din,
that’s basically what the old dimmer switches do

 

[DPG]

The coil in traditional dimmers is there to absorb spikes caused by the triac switching on and off at the peak.
A triac is basically just an electronic on off switch..
Remember as a child when you would hold a switch till the light flickered din,
that’s basically what the old dimmer switches do

Lovely analogy for phase angle control.
Mind you, I know what you originally put that post . Only kidding.

 

[dean.diy]

My friend says thanks for info, Charlie.

 

[Tony Reidy]

yesterday was working in a house where a different sparky had installed LED spotlights on dimmer switches. the leds flicker when you dim them. also the mcb the lights are on buzzes when the LEDs are on - to do with harmonics I think. But the funny thing is I know another house that was done by the same sparky with the exact same problems. Why would he keep doing that - surely he would have learnt?? and is it only certain combinations of dimmers and LEDs that flicker because I constantly install LEDs on dimmers but they never flicker?

What dimmers do you use

 

[Barnaby Stedman]

Well its not me - I think they were BG nexus but not sure exactly what spec - will try and find out

 

[Charlie_]

Lovely analogy for phase angle control.
Mind you, I know what you originally put that post . Only kidding.

Thank you, I like to put things in layman terms and use analogies where possible, whenever I get too technical I’m usually confronted with a blank face

 

[DPG]

Used to have a lecturer (at Donny college near the Waterdale - you probably know it) who came up with some cracking analogies, but they normally didn't make sense unfortunately. He once likened thyristor operation to the height adjustment on a lawnmower when we were doing power electronics

 

[Charlie_]

One of our lecturers used to always use mnemonic rhymes..
Used to be sat there doing revision or sitting an exam singing bloody rhymes like a racist to remember resistor codes

 

[Bobster]

One of our lecturers used to always use mnemonic rhymes..
Used to be sat there doing revision or sitting an exam singing bloody rhymes like a racist to remember resistor codes

I remember being taught something similar, not racist, but certainly not nice haha

 

[DefyG]

Incompatible dimmers to lamps to dimmers whichever way you look at it.
Bane of an electricians life dimming LED but usually there is a combination out there that will work!

 

[FatAlan]

Currently using BG Nexus dimmer with JCC V50 led downlights ... no issues. If I’d installed something that didn’t work for whatever reason I’d want to know and would also fix. If I was the customer I’d want the spark back to sort!