GU10's Blowing....

Afraid the answer is they are GU10s, they are infamous for short lamp life, only lamp makers can get 2k hours out of them.

In meantime dimmer will slow start lamps and may(1) marginally improve lamp life , usually yellow enough without dimming them much though.

Replacement with something using low voltage halogen is best course really, MR16 is same lamp size with much higher efficiency, higher colour temperature and decent lamp life.

Cheers Adam

(1) Personally believe it helps, not a universally held view.

I would guess at vibration. Mains voltage filaments aren't all that rugged s a bit of shaking about doesn't help at all. The 2000hr rating won't be all that accurate anyway, but it will be based on a no-vibration installation.

If your lamps are intended for the European market then they could actually be 220v or 230v filaments.

If you could drop the voltage below 240, even just slightly (say 235) you would almost certainly get much better lamp life! Lamps are surprisingly sensitive to voltage. Some traffic lights run 12v halogen bulbs at 11.8v. Not a big difference, but helps a lot with lamp life.

They don't like vibration. So heavy foot traffic in the room above etc does not help. Dirty switch contacts can be another problem. Halogens also last longer with soft starting. Alas, compared to the 12V versions they have little to recommend them.

Dirt cheap to install.

Some people think they look fashionable. I think they look dirt cheap... ... except the the running costs, that is.

Because 35W mains halogen bulbs have a lifetime measured in minutes.

Especially from VERY cold starts.

Go LV.

They are

In article , aswell13 writes

Vibration? Are your kids leaping up and down on the floor above?

If you can bear the shape (longer in the bulb), cost (c=C2=A310 each), and the colour temperature, Megaman 11w GU10's are OK in some locations. I use them in a perpetually lit hallway (perpetual in the recent weather anyway). They should be ideal for shop display.

R.

Door banging shut?

I would look at using concieled fluorescents, or if you really need spots of lighting, small metal halide. The latter are expensive, but in a 24x7 environment, they should pay for themselves in a few years, which is why they're used in shops. (Payback is even faster if the shop has air conditioning, so you pay again to get the heat out.)

Might get more suggestions if you put up a picture of the window display on a website for comments.

or even _concealed_ (don't know how I managed that).

If they last anywhere near the advertised 15,000 hours then yes, but if like the ones I have installed they start blowing at 900 hours then they are a very expensive option.

pcb1962 wibbled on Wednesday 02 December 2009 11:32

Hmm. I was persuaded into getting a couple of GU10 based mains fittings for the kid's bedrooms. Starting to regret that now... Maybe LED GU10s will get decent by the time I get fed up changing the lamps.

I'll look into SELV spots for the couple of other places were spots are destined. At least I've got soft start dimmers lined up for said lamps for what that's worth...

Somewhere in my past I've come across a figure of bulb life is voltage raised to the power 10. I'm not going to mess around with the maths but a quick check on the web found a graph showing a 5% change in voltage doubling / halving bulb life. The voltage range of mains in the UK exceeds +/- 5%.

Rob

Is it possible to replace mains voltage GU10s in a 'standard lamp' with a low voltage alternative? Where would the transformer go?

There are some decent looking ones already. But they are massively more expensive than halogens so only worthwhile if they last a lot longer, and one of the ones I got recently has just died, lasting no longer than GU10 or MR16 have in the past in the same place.

Alan Braggins wibbled on Wednesday 02 December 2009 13:09

Think I'll hold off for a bit there Alan then ;-)

I said to SWMBO "if you want spots, lets standardise on GU10s as a) I don;t have a box of spares with half a dozen lamp fittings permuted by wattages; b) if anyone starts to make convincing low energy replacements, GU10 seems to be a fairly ubiquitous fitting so best chance of getting something better down the line"

I thought it was fairly logical, but who knows...

Nope, but can usualy get the real fitting that the GU10 version is the cheaper knock of of.

GU10 is a strange format that simply dosen`t work.

Cheers Adam

Yeah, we have 4 rooms with dimmable multi-GU10 lighting (26 fittings in all, I think...). They seem to run well enough, a bulb needs changing every few weeks but that's acceptable in time and cost. The only real nuisance is that when they fail they invariably flip the RCD for that circuit.

No. the currents are way higher, so you need MUCH fatter cables. Transformers can go anywhere within a meter or two but need FAT wires to the FAT fittings. LV bulbs are NOT GU10 compatible for that and safety reasons.

New fittings/trasnformer time. But they are not expensive. £10-£20 per bulb. Pays for itself in bulbs in a year or so.