Dimmers keep blowing

[joebb]

Can anyone advise me? I have changed 5 dimmer switches in a pub and after around 2 months they stop working this has happened twice now. I have put 1000 watts dimmers as the load is 700 watts, so I not overloading it, could it be that the lights are on for around 12 hours everyday?

 

[solo2771]

did the same myself few mnths ago with no problems.
sure all lamps are dimmerble and there is no spurs?
also are they all around 700w circuits? any much lower?

 

[joebb]

Cheers 4 reply, no there are no spurs on the circuit, and the lowest load is 400 watts

 

[electric-ian]

Any LV transformers on the circuit... even dimmable electronic ones can cause problems if you've got more than 5 on a dimmer ?

 

[bugsy]

Fit a commercial dimmer i assume thats 700w on one circuit.
Mode electronics do 1500w dimmer packs , use mode quite a bit not bad kit for stand alone dimming

 

[pennywise]

Check all the lamps as said above, I do a pub and I put in a 1kw dimmer, I told the landlord specifically not to put non dimmerable CF lamps in, went back the other day all but 3 were non dimmerable CF lamps prat!. Next time they go I'm putting in wise control florescent dimmers then he'll probably go back to incandescent lamps, can't win

Richmond lighting do very good quality commercial dimmers too

 

[richiek]

Are any of the lamps using energy savers as these are not compatible with dimmers and will blow the internal components in the switch in a very short time?

 

[Darkwood]

Check the info with you dimmer, some styles of lamp like gu10's require a 50% reduction to the rating of the dimmer so your 1000watt dimmer may only be good for 500w of gu10 lamps, if this is the case get a dimmer that can be used with the lamps involved without a reduction to the dimmer rating.

 

[joebb]

Thanks

 

[Johno]

darkwood is right. when you choose a dimmer it has to be the right one, some dimmers can only dim halogens at 50%, and also, if dimming 12v halogens you may need a different dimmer altogether and then the amount of trannies comes into play. basically be very cautious with dimmers. i normally buy mine from TLC and they are helpful

 

[Deleted member 9648]

Cheap GU10's have been known to knock out a dimmer when they blow even with the correct derated dimmer fitted....they go with a hell of a bang sometimes.