Dimmer switch 'blown'

I bought a new on/off + dimmer switch last week. It controls a 3 x 60 w chandelier. One bulb blew tonight and as usually happens tripped the RCthingy. When I re-set the switch the on/off works, but the dimmer doesn't. Is this to be expected every time a bulb blows as it will work out quite expensive?

Reply to
Jim S
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Possibly. I would say it is the fault current going through the dimmers winders (or electronics?) that have damaged the dimmer.

I damaged one last year by cutting through a lighting cable - there was probably 300-500 amps going through the dimmer for the time the earth and live were joined, until the circuit breaker tripped, just like when a lamp goes, it will cause a live to neutral fault current, which can be hundreds of amps for a short time.

Reply to
A.Lee

You didn't buy the dimmer from B&Q, did you? I've had exactly the same problem and will soon be on my third one. Useless crap. Regards, Terry.

Reply to
terry.shitcrumbs

No but it used to happen to me a lot. In fact I even bought some cheap triacs in a box so I could replace them. Obviously now I don't use lights, but I never did understand why the system was so sensitive to momentary shorts. Brian

Reply to
Brian Gaff

It's said a solid state device is there to protect the fuse supplying it. ;-)

In the fuse rather than MCB days, I've had a lighting circuit one blow when a bulb fails. Producing a dimmer which would stand that sort of load might be expensive.

Reply to
Dave Plowman (News)

get your money back. Or open it up and put in a bigger triac

Reply to
The Natural Philosopher

Bulbs blowing often draw a surge of current (hence tripping the MCB for the circuit). Dimmers also often have an internal fuse. So that may have blown as well.

Reply to
John Rumm

aka 'Triac'

So that may have

Reply to
The Natural Philosopher

In article , John Rumm writes

The triac will sacrifice itself to protect the fuse.

Reply to
Mike Tomlinson

Fit a new triac. It happens once every so many bulb blows, and yes, it is a pain. Use halogen-in-candle lamps and it'll happen very frequently. There are other ways to dim incandescent lamps, eg switching a capacitor in serie s with the bulb, or using a transformer to reduce voltage. Those can be don e at the wall switch, though the bits need extra space made for them.

NT

Reply to
meow2222

Although I probably could, I am not into faffing around 'fitting new triacs'. I just regard myself as being unlucky that my dimmer was the one that blew in those circumstances. Shit happens. I replaced it with a non-switching dimmer that I bought by mistake and if it goes then I will just go back to a conventional switch. Life's too short.

Reply to
Jim S

Or switching a series diode in and out, or wiring lamps in pairs so they can be switched in series or parallel.

Must confuse the pants off the unsuspecting electrician who comes to fault find.

Reply to
Graham.

Just done a quick count and I've got 18 dimmers here. Many of which over

30 years old. I've replaced perhaps two. The majority are Home Automation in grid switches.
Reply to
Dave Plowman (News)

Sometimes... the only time I had a dimmer fail on a bulb blowing, a new fuse in the dimmer fixed it.

Reply to
John Rumm

s a pain. Use halogen-in-candle lamps and it'll happen very frequently. The re are other ways to dim incandescent lamps, eg switching a capacitor in se ries with the bulb, or using a transformer to reduce voltage. Those can be done at the wall switch, though the bits need extra space made for them.

I found that caused severe flicker. 120v lamps have much thicker filaments.

far too much dimming

NT

Reply to
meow2222

I'd say it must depend on the type of lamp in use - as well as perhaps the individual. I've used it with success - so worth just trying since a suitable diode costs pennies.

Reply to
Dave Plowman (News)

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