dimmer swtch keeps blowing 240v

[purkyuk]

Hi guys,
When fitting a dimmer switch in one of my bedrooms it manages to blow the switch. From day one there was a single plastic light switch with just COM and L1. The dimmer is a direct replacement ie. COM / L1 and earth as its chrome fitting. So far its killed 3x dimmers even one that has been workin fine in another room for years. The light is single 40w bulb. When the dimmer is fitted and tested it works but when turned to low light it flickers then eventually the dimmer doesnt dim anymore then it dies. the ceiling rose looks ok and wiring seems correct... However, some reason why its burning them out is puzzling me... Any help greatly appreciated!!

 

[1john]

Is there a minimum load on the dimmer?

 

[wingcoax]

What type of bulb/lamp are you using?

 

[riveralt]

Hi guys,
When fitting a dimmer switch in one of my bedrooms it manages to blow the switch. From day one there was a single plastic light switch with just COM and L1. The dimmer is a direct replacement ie. COM / L1 and earth as its chrome fitting. So far its killed 3x dimmers even one that has been workin fine in another room for years. The light is single 40w bulb. When the dimmer is fitted and tested it works but when turned to low light it flickers then eventually the dimmer doesnt dim anymore then it dies. the ceiling rose looks ok and wiring seems correct... However, some reason why its burning them out is puzzling me... Any help greatly appreciated!!

Are you sure that the original wiring puts the live in Com and the switch live in L1.
Putting them in the other way around doesn't normally affect standard switches nor indeed most dimmers.
But some dimmer instructions require them to be spefically connected live to Com and switch live to L1.

 

[purkyuk]

Hi guys,
firstly thanks for all your replies.
The power rating of the dimmer is 400w
the bulb is a simple candle with BC connection 40w
i tried on the second dimmer to put the perminant live in L1 and switch live in com, just as the instructions say. But still the same problem.
The ceiling connection is a simple pendant type (cheap cheap) with the light ring loops in the top.
Ive fitted 3x dimmers (same day/ made/ type) in other bedrooms without any probs.
Im confused...

 

[riveralt]

Hi guys,
firstly thanks for all your replies.
The power rating of the dimmer is 400w
the bulb is a simple candle with BC connection 40w

Yes but what is the dimmer range 0-400w or 50-400w?

i tried on the second dimmer to put the perminant live in L1 and switch live in com, just as the instructions say. But still the same problem.
The ceiling connection is a simple pendant type (cheap cheap) with the light ring loops in the top.
Ive fitted 3x dimmers (same day/ made/ type) in other bedrooms without any probs.
Im confused...

I take it a normal plate switch works?
And there are no other cables at the switch other than the Live/switch live and earth.
And no loose cables at the ceiling rose?
If not, a clear photograph of the wiring arrangement at the ceiling rose might help.

 

[purkyuk]

Just checked the rating and its 60 to 400w.
As i was running a 40w bulb will this blow the fixture?
Thanks again for your help

 

[purkyuk]

Just checked the rating and its 60 to 400w.
As i was running a 40w bulb will this blow the fixture?
Thanks again for your help

 

[Taylortwocities]

That's your problem.
The dimmer needs at least a 60W lamp or it will die after a while. Underlaoding a dimmer is as harmful to the electronics of the dimmer as overloading it.

Either put a bigger wattage lamp in, or get a dimmer that will allow you to use a 40W lamp, a 250W dimmer may be OK but check its a 0-250W dimmer.

 

[purkyuk]

Well well, you learn something new everyday!
I will try it again with a 60W bulb tonight.
Again thanks to everyone who replied and helped!!

 

[johnnykc]

That's your problem.
The dimmer needs at least a 60W lamp or it will die after a while. Underlaoding a dimmer is as harmful to the electronics of the dimmer as overloading it.

Either put a bigger wattage lamp in, or get a dimmer that will allow you to use a 40W lamp, a 250W dimmer may be OK but check its a 0-250W dimmer.

Standard dimmer loadings are 60-400w and 40-250w