Fuse required for dimmer with Halogen lamps?

Keep in mind the definition of an electronic device as an expensive piece of equipment designed to go open circuit thereby protecting a cheap fuse from failure in the event of a circuit fault.

You should have bulbs with a fuse - frankly I'm surprised you managed to find some without, even cheap bulbs usually have one. If not, the bulbs can fail short-circuit and blow the dimmer before the main circuit breaker can trip. Unless you've got a really odd type of bulb, you should be able to buy fused ones just about anywhere, which will be a lot cheaper and easier than messing about rewiring the holder. Then you just need to remember to check when you buy bulbs in future.

Mike

You forgot to mention whether theyre mains or 12v halogens. The 2 are quite different animals, and the resulting advice also different.

NT

Four of these...

I have no idea whether they have or haven't - they came with (in!) the fittings - is it possible to tell visually?

If not, I'll just get these I think...

Cheers, David.

adding a fuse can improve the odds of dimmer survival to an extent, but yes, drying mains halogens are prone to killing the dimmer.

If your dimmer has soft start, the fuse can be a good bit lower rated, which all helps.

replies above. You could also do yourself a favour and go over to 12v halogens. Better energy efficiency, less run cost, better bulb life, less premature failures, safer, no dimmer kills.

NT

adding a fuse can improve the odds of dimmer survival to an extent, but yes, drying mains halogens are prone to killing the dimmer.

If your dimmer has soft start, the fuse can be a good bit lower rated, which all helps.

these...

replies above. You could also do yourself a favour and go over to 12v halogens. Better energy efficiency, less run cost, better bulb life, less premature failures, safer, no dimmer kills.

NT

I once heard that "Touch Dimmers" have different control circuitry and cope better with bulbs blowing - and they always give a soft start.

None of these have fuses. Halogen lamps generally aren't fused, unless the halogen capsule is inside a standard glass outer bulb with fuses in the frog.

Fusing halogens is pretty mandatory, as they can otherwise blow up if they have a flashover when the filament breaks (albeit much less likely than with a GLS lamp because the gas pressure is much higher and less likely to form a sustained arc).

"bulb has strengthened glass cover with Built in safety fuse" - wrong picture, or lying?

I'm utterly confused by your post Andrew. "Halogen lamps generally aren't fused", "Fusing halogens is pretty mandatory", but GLS lamps are even more of a problem?

I've never seen a Halogen fitting saying it requires a separate fuse, much less so a good old fashioned GLS light bulb (apart from whatever is in the CU of course).

Am I missing something?!

Cheers, David.

They're triac switchers like all modern dimmers. You'd have to go back several decades to find anything else.

NT

these...

They're triac switchers like all modern dimmers. You'd have to go back several decades to find anything else.

NT

Mine claims to handle overloads by switching off.

It might handle lamps of too high a wattage gracefully, but it doesnt have a hope in hell of handling the 60-200A an arcing bulb consumes.

NT

One of the halogens has blown (yes, that was a _very_ short life - two weeks!). The dimmer (it is a touch soft-start jobby) has survived.

I doubt it'll always be so lucky - but I was hoping to have longer to get something to protect it in place!

Cheers, David.

Nothing will protect it.

NT

Nothing is ever simple. I bought these, and they arrived with a helpful note: "Out of stock - sent you more expensive energy saving bulbs instead"

Can you dim energy saving halogens? They're not some CFL or LED based thing - just a variation on a normal Halogen by the look of it: 100W of light for 80W of power. No mention of a fuse though. :-(

Cheers, David.

They behave just the same as regular halogens. Energy saving is an optimistic description for halogens. They'll presumably have an IR reflective coating that sends lost IR heat back to the filament.

NT