Switched To Led Bulbs - Problem With Dimmer

[MadDoc]

Hello,

I had my house completely rewired 5 years ago. At that time I had 12 GU10 35W halogen spotlights fitted in my lounge, controlled by a simple rotary dimmer switch. 

I have just replaced the bulbs with 12 5W dimmable GU10 spotlight LED bulbs. They work but there are two problems:

1. The range of "dimmability" is really narrow. When the dimmer is turned right down, they are still pretty darn bright (I don't think they are dimming much at all).
2. When I turn the lights on by clicking the dimmer switch, they flicker a lot unless the switch is turned to at least halfway on. Once on, I can turn the dimmer down and they don't flicker.

Do I need to replace the switch with a special one for LED bulbs? Is this just a straightforwards swap if so or a more major job that would need an electrician to help with?

Thanks,

 

[Blue Duck]

Load is too low for normal dimmer.

Try slipshod & slapdash's favourite http://www.tlc-direct.co.uk/Products/VLJP400MOD.html?source=adwords&kw=&gclid=CInxlZK_pMICFcjHtAodqEsAkA

Used one the other, day lots of functionality for a dimmer!

 

[MadDoc]

Ah. Do they make switches which fit the standard size switch boxes so I can just straight swap then out? What's a trailing edge? Is that important?

 

[Doc Hudson]

Ah. Do they make switches which fit the standard size switch boxes so I can just straight swap then out? What's a trailing edge? Is that important?

Yes trailing edge is important, it is to do with how the dimmer chops the alternating mains supply to dim the lights. You must also have dimmable LED's. Some LED's are not dimmable. 

Doc H.

 

[Blue Duck]

You need to double check with the lamp manufacturer as to what is best. I used that dimmer for some cheapo 5w dimmable candles and it worked fine

 

[Doc Hudson]

In some cases it is possible to damage either the dimmer or the lights or both if they are incompatible. The damage may result in a reduced lifespan, not just a simple stopped working straight away.

Doc H.

 

[Blue Duck]

There was no info to refer to on cheapo unknown lamps so just hope for the best :C customer had already blown £30's worth with a normal dimmer :|

Always try fit good brand LEDs.

 

[Doc Hudson]

Ah. Do they make switches which fit the standard size switch boxes so I can just straight swap then out?

If there was a dimmer switch in there before then another dimmer should fit without too much problem. But a standard switch in a 16mm back box can be a bit of a tight fit for a dimmer without either spacers at the front or sinking a deeper box.

Doc H.

 customer had already blown £30's worth with a normal dimmer .

Ouch!

 

[MadDoc]

Thanks everybody. There's no instructions with the LED bulbs (bought from B&Q). The product code is 5052931112500[SIZE=1em] ([/SIZE]can't post a link as I don't have enough forum posts yet and the forum won't let me) so I'm not sure if I need a dimmer with a trailing edge or not...

I shall try and find a replacement switch today. I'm assuming its safe to use until I get a replacement (I'm working nights this week and don't want a fire risk for the wife and kids at home!).

 

[Blue Duck]

http://www.diy.com/departments/diall-gu10-5w-spot-led-light-bulb/237390_BQ.prd

not much info there either... What a surprise...

 

[Doc Hudson]

Those LEDs are quite a poor lamp in my opinion. For a 5watt lamp the lumen's output is quite low (250lm) and they have a narrow beam angle, (350).  With a 5watt lamp I would be looking for 320lm -> 350lm+ and probably 450 or 600 beam angle. Of course it depends upon the type of light you are after, but for general room lighting I think a bit more spread helps light the room more.

Doc H.

 

[kerching]

Ah B and Q.....contact their customer services department

Tell them what you have bought

Get them to tell YOU what is a suitable dimmer AND get it in writing that it is suitable

Good luck with that one

You do not want to knacker a load of lamps AND a dimmer...put the ball in their court

Just being quite calm

 

[Dal Roberts]

http://www.lyco.co.uk/advice/dimmers-trailing-edge-v-leading-edge/

A good Article on Trailing & Leading Edge Dimmers peeps

 

[copperknob]

a lot of consumers fall for the whole dimmable led lark. Unfortunately manufacturers dont even bother with the small print which should explain that a lot of the time it wont work as a like for like change. Can of worms unless you ensure compatibility (spelling) between the dimmers and lamps.

 

[NozSpark]

I've even seen a leading edge dimmer labelled up as being compatable with LEDs.... Now I'm sure that all the LESs that I've seen need trailing edge dimmers so where do they get that info from