installed a dimmer switch, but bulb blowing . .

[theflyingpig]

Hi all,

At the weekend I replaced a 2 way switch with a dimmer - wiring definitly correct but it blows the bulb. I have a multi-meter - anyone tell me how to test the dimmer?

thanks!

 

[FatGit]

What sort of blub?

 

[theflyingpig]

standard filament type - treid both 60w & 100w

 

[jj4091]

blows the lamp when? at switch on? when dimming? what sort of dimmer?

 

[theflyingpig]

at switch on, its rated 400w, minimum 60 w - but it is a two way light I'm wiring it into - direct replacement for a two way switch . .

thanks

 

[luminaire]

Can't you just take the dimmer back and get it replaced? It could be a faulty dimmer.

 

[theflyingpig]

sure - i just wondered if there was any other obvious reason this might happen - ie/ wiring not up to the job?

 

[FatGit]

Could be cheap blubs. Try a more expensive type.

 

[luminaire]

Suggest replace dimmer and see if this solves your problem. If not then the fault is elsewhere like the wiring.

 

[bernardgreen]

There is a small chance that the dimmer may be over volting the lamp.

Some dimmers when working at or below their minimum power rating have been known to produce voltage spikes greater than 240 volts ( from the inductor intended to smooth the output ). These could be causing the bulb to blow but it seems very unlikely.

Try replacing it with a dimmer of lower power ( but don't go for cheap one )

I assume you know the bulbs have blown by testing them elsewhere. Someone I knew put 3 bulbs in the bin before realising the fuse in the table lamp plug had blown

 

[theflyingpig]

they are blown all right! but they are definitly cheap bulbs so between that and trying a differenet dimmer I've got some options.
I guess I curious about the wiring - why would it need to be any diffrent for a dimmer than a standard switch?

thanks

 

[breezer]

wiring is the same.

many many years a go, i had an "electroic toy" i found out that if i twiddled the little knob lamps didnt last longer than say 1 second, turns out it was, as suggested putiing around 700v through the lamp

 

[theflyingpig]

so its not nessesary to ugrade the wiring then? someone here at work suggested 'old' wiring wasn't up to 2 way dimming . . .
the thing is I want to replace the current single pendant with a lighting track and maybe 4 spotlights - mmmmmm, might get a bit expensive if I start blowing them!

 

[Albert]

I would put back the original switch (does not take long) and see if the bulb is ok. If it does not blow it means that probably the dimmer is the cause, if it does blow means there is something wrong in the way it is re-connected...

 

[theflyingpig]

thats exactly what I've done - twice! replaced the dimmer with the switch and no problems. logic dictates it must be the dimmer . . was £10 from QVS which doesn't seem that cheap to me . .