Ask The Trades - Print Page

Ask The Trades
https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Electrical Questions >> LED lamps glow when dimmer is Off https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1646071303 Message started by Flashbang on Feb 28^th, 2022, 6:01pm

Title: LED lamps glow when dimmer is Off
Post by Flashbang on Feb 28^th, 2022, 6:01pm

Hi all
I have two three lamp ceiling light fittings controlled by one dimmer switch. Each fitting has three LED lamps (6 in all). I changed the dimmer switch for a LED dimmer switch which is also Alexa controlled Here ... https://www.amazon.co.uk/gp/product/B091HP42S8/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
But when Off the LED lamps all glow very slightly. I believe this is caused by inductance occurring between the live and switched live wires between the light fittings and the dimmer switch?
I understand that fitting a Bypass (Capacitor?) across Sw Live and Neutral in the first light fitting will stop this glow, But what capacitor?- Type make etc would be very helpful or an alternative suggestion? UK based.

Thanks in anticipation

Title: Re: LED lamps glow when dimmer is Off
Post by Lectrician on Feb 28^th, 2022, 6:52pm

Most dimmers these days, especially if designed for LED, will not cause the lamps to glow. That said, things like PIR detectors can. Danlers do this:

https://www.tlc-direct.co.uk/Products/DNCAPLOAD.html

I have used this on some dodgy dimmers.

Title: Re: LED lamps glow when dimmer is Off
Post by Flashbang on Mar 1^st, 2022, 12:50pm

Hi

Thanks for the link etc. I had seen those before, but understood (wrongly?) they were for specific use with Danlers products - Dimmers etc.
Last evening I replaced one LED lamp with a conventional 40watt filament lamp and the flickering/ glowing ceased immediately which points to the induced voltage in the switch line to the light fittings
Annoyingly the six LED 5watt lamps were not cheap nor was the trailing edge dimmer. :-[

Title: Re: LED lamps glow when dimmer is Off
Post by Natedog on Mar 1^st, 2022, 10:15pm

What bulbs are you using? Decent LED bulbs normally would have a fairly high value resistor across the input to stop the dim glow, in the same way your filament bulb (basically just a resistive load) is doing

Title: Re: LED lamps glow when dimmer is Off
Post by Flashbang on Mar 2^nd, 2022, 10:35am

Hi
The six LED 5watt Golf ball lamps are all from a company called Ahead renewable energy. A British company it says on the lamps box located in Theale, Berkshire! But made in PRC which I take to be Peoples Republic of China? Perhaps they are not the best after all? Box states they are dimmable. None the less, any lamp purchased should work as expected - correctly! Otherwise they are not fit for purpose. :-?