dimmer switches

[mrcrow]

we have a dimmer switch of the type where you push the switch on and then rotate it
its rated at 600-1000W
it controls 5 halogen GU50 in the bathroom = 250W
recently one of the bulbs went and then the dimmer part wouldnt work
the dimmer switch was replaced
another bulb went and subsequently also affected the dimmer switch dimming facility
the bulbs i can see were faulty and am happy to change them
the dimmer is something different

what could be the reason for this if the two incidents...bulb failure/dimmer failure are connected

at present i just use the on off part of the switch..its outside the bathroom...and wont replace it till i can understand what may be the cause of failure

 

[bongos]

I understand that if you have rubbish transformers installed then these can sometimes lead to further problems where a dimmer is concerned.

People on this site often advise installing a decent transformer when using these type of lights because of the problems that can occur with a bulb blowing and then this can sometimes lead to dimmer failure.

Another possibility is maybe it is a cheap dimmer that doesn't last well but then the wattage operated by it seems well within its boundaries. Maybe you've just been unlucky! Can you take it back and suggest that it doesn't work

But i'm no spark so i'm sure someone more qualified will provide some suggestions.

 

[securespark]

Did you mean GU10? If so, these don't have transformers.

But, unless the dimmer is able to switch tungsten halogen loads without derating, for a 250W load, you'll need a 500W dimmer.

You say yours is 600W-1kW: sure thats right?

That suggests your dimmer needs a minimum load of 600W. Did you put one too many zero's on it?

What brand are these lamps? If unbranded, they could be poor quality. Also, they may not have internal fusing. If they don't, then the lamp failure could well be toasting the dimmers.

I know MK dimmers now have a warning in the box - something like, fit quality lamps fitted with internal fuses or else when the lamp fails, it will damage the dimmer.

So, buy quality lamps (Osram are good) and make sure they're all changed before you replace the dimmer.

 

[mrcrow]

Did you mean GU10? If so, these don't have transformers.

But, unless the dimmer is able to switch tungsten halogen loads without derating, for a 250W load, you'll need a 500W dimmer.

You say yours is 600W-1kW: sure thats right?

That suggests your dimmer needs a minimum load of 600W. Did you put one too many zero's on it?

What brand are these lamps? If unbranded, they could be poor quality. Also, they may not have internal fusing. If they don't, then the lamp failure could well be toasting the dimmers.

I know MK dimmers now have a warning in the box - something like, fit quality lamps fitted with internal fuses or else when the lamp fails, it will damage the dimmer.

So, buy quality lamps (Osram are good) and make sure they're all changed before you replace the dimmer.

yes GU10..
the ones i bought to replace the duds are general electric 1000 hours type
the originals put in by the electrical engineer have the name ring on them
i have some osram in the cupboard..but are 30W...

i will check the capacity of the dimmer again....

but i get the message..

i really didnt know it was so involved having a dimmer...

how can i tell if a bulb is fused ..would it say on the box
cheers

 

[mrcrow]

ring lighting have emailed me back that their lamps are fused and i should check the dimmer manufacturer to check if this dimmer is suitable for GU10 bulbs

 

[johnnykc]

cheap GU10 lamps do not have fuseable links so when they 'blow' the spike can well damage a dimmer switch. (regardless of whether its a cheap or expensive dimmer)


the answer is to only use proper branded GU10s (philips, GE,osram or sylvania) NEVER one of the millions of cheap lamps that wing their way to our shores.........

 

[mrcrow]

cheap GU10 lamps do not have fuseable links so when they 'blow' the spike can well damage a dimmer switch. (regardless of whether its a cheap or expensive dimmer)
the answer is to only use proper branded GU10s (philips, GE,osram or sylvania) NEVER one of the millions of cheap lamps that wing their way to our shores.........

thanks..i did post that the GU10 bulbs were by RING
i emailed them and they confirmed their bulbs were fused

strangely enough the cheapy tesco GU10 has 'dimmable' written on the box but are no cheaper than internet bargains in 10's etc (listed as 2000 hours and fused)

a puzzlement for a simple lad