Problem with a pendant light fitting

In mum's house, in the lounge there's a pendant fitting that has three sort of goblet/vase-shaped metal cones which face upwards at the ends of three metal arms. The cones have frosted glass 'petals' in them. The bulb holders are small edison-screw fittings mounted somehow in the metal parts of the cones. I'm having to change bulbs in this unit very often; partly I think the problem is that although hot air from them can drift upwards, there's nowhere for cool air to flow into the base of each cone, so I think the bulbs get very hot and their life is shortened.

There's also clearly a problem with poor contacts somewhere in the SES bulb sockets, as quite often an apparently failed bulb will work again if it is turned a few degrees in its socket.

I could possibly take the whole unit apart, but there's litte point unless anyone knows of some place which stocks SES sockets with (presumably) various types of mount, so I might be able to find one sort that would fit the whole unit.

Or, just maybe some manufacturer has an adapter - perhaps very slightly larger than a normal SES bulb's thread, and with a spring of its own at the bottom where the blob contact on a normal SES blub is - that can be screwed into an existing SES socket to produce an effective new socket an inch or so further out?

Does anyone know of SES sockets, or adapters like this? Or know of any way to make a poor contact SES socket reliable again?

Reply to
Jeremy Nicoll - news posts
Loading thread data ...

How often is "very often"? How much per day is the light on?

Most incandescant lamps are rated for 2000 hrs you have three so on average you will be replacing one every 2000/3 hrs call it 700 hours.

10 hrs/day is 70 days or every couple on months. The light could well be on for the best part of 18 hrs (0700 - 0000) that gives 38 days, every month(ish)...

We have a similar fitting but upward solid glass bowls, I never felt it was overheating that caused shorter bulb life. The rising air next to the bulb will draw cooler air in down the sides of the bowl. Enclosed fittings like bathroom globes are another matter.

Our problem was a rather high mains voltage, it would peak just outside the upper tolerance of 253 V and had an average >245. Only spotted when I bought a UPS and it went straight into "voltage trim" mode... Called the DNO, they came round, measured agreed, and adjusted a tapping on our pole transformer. Volts down to 240 average, bulbs lasted much longer...

Another possibilty for short bulb life is vibration, though if you are using 40 W candles they are pretty robust compared to higher wattage lamps. Is the floor/ceiling a bit springy?

It is a hot enviroment maybe the contact in the base of the fitting has lost a bit of it's springyness, try levering it up a bit. Also give ita bit of scrape to remove any oxide. Power off of course... B-)

Is the threaded part metal or plastic with another bendy bit of metal to make contact? If a bendy bit of metal adjust that so it will make contact with the lamp base.

Reply to
Dave Liquorice

Take the fitting down, clean up the contact surfaces, make sure wire pinch screws are done up properly, refit.

Filament lamps are normally 1000hr rated, so you should be replacing one every 333hrs of use on average. Xenon ones are generally 2000hr rated, so one every 667hrrs.

Bare CFLs look particularly bad in chandeliers, but if they fit and are covered by shades they should do fine, and last 10x as long.

NT

Reply to
meow2222

Getting at the spring in the bottom of a SES socket is going to be hard, I think, especially to pull it 'upward' a little.

The bulbs look outwardly like old-fashioned filament bulbs but are actually a small halogen bulb mounted inside a globular enclosure. They're rated at

2000 hours. Mum doesn't usually go into tyhe lounge until about 5pm, then may watch TV on & off until around 11pm, so 6-7 hours per day would be the use I'd expect. Thus I'd expect roughly 2000/7 = 285 days' use, say about 9 months.

For a year or two I've been recording when I change a bulb, and in each case which position in the group is being changed, and have noticed that I'm doing so significantly more often. I don't have a ohm-meter at mum's house though so don't verify that a non-functioning bulb is actually blown, but do usually check that slightly tightening the bulb in its socket doesn't make it suddenly work. It's possible that some/all times I haven't checked the bulbs have been ok and just replacing them made a better contact.

Recently bulbs have lasted as little as 3 weeks, though around 4 months seems more usual. Some have lasted around 9 months.

The bulbs I'm using are eco-halogen, 45mm diameter, 78mm length, E14 (SES), that look like:

formatting link
though they've been B&Q's "Dial" brand. They're 42W. I have a feeling that we previously used a candle bulb of some sort, though can't recall the rating.

The cone/shade is very narrow and after candle-shaped bulbs ceased to exist (in local shops at least) I thought we were lucky to find the eco-halogen things.

Reply to
Jeremy Nicoll - news posts

is that "eco-halogen" a.k.a "halogen"?

Reply to
Andy Burns

Probably. I guess it's just marketing speak to make what looks to a casual glance like a normal globular filament bulb seem special in some way. OTOH I did see the term quite a lot while googling on the topic.

Reply to
Jeremy Nicoll - news posts

It seems theyre really xenon, not halogen

NT

Reply to
meow2222

With the fitting still on the ceiling yes but not on the table. Might need a bit of stiff bent wire to hook under to pull upwards. Hasn't Aldi got a set of spring hooks on offer from Thursday? Yes, they do £2.99 set of four but probably too big for this application.

Per lamp, you have 3 so divide that 285 by 3 = 3 months

The "4 months seems more usual" is close enough to a 3 month average. We had two fittings with 3 lamps each, that really was a lamp every month until we got the voltage sorted out. That did improve things but we switched to CFL not that long afterwards and almost forgot how to change 'em. B-)

Halogens are fragile particularly when hot.

Reply to
Dave Liquorice

I might get away with a bit of massacred coat hanger...

No, I don't think so. I think you're saying that on average one would replace a bulb every 3 months, which I agree with. But any individual bulb should still last approx 9 months surely?

If a bulb only last 3 months, then I'm getting 90 days * 7 hours = 270 hours out of it, not 2000 hours.

I've not just recorded how often I change a bulb, but instead when I change the bulb in fitment 1, when I change the one in #2, and when I change the one in #3, so I know the length of service of each bulb.

Reply to
Jeremy Nicoll - news posts

Do they blow on switch-on or "in service"? If it's the former you could fit a dimmer switch to start them up gently. You need the type where the on/off switch is part of the rotary action, not the push/pull ones.

Chris

Reply to
chrisj.doran%proemail.co.uk

halogen is a generic term for certain gasses, xenon is one of them.

Reply to
charles

Bit of confusion between Halogens and Noble gasses, methinks.

Reply to
Andy Burns

I'm not a chemist.

Reply to
charles

months.

True, I hadn't picked up on your record keeping being per lamp rather than "I only did that last month" across the fitting.

I'd clean and rebend the contacts, monitor the supply voltage when the light is in use and, as these are halogens, see if there is vibration being conducted down from the floor above.

Reply to
Dave Liquorice

Halogens = Fluorine, Chlorine, Bromine, Iodine (and the practically non-existent Astatine).

Noble gasses = Helium, Neon, Argon, Xenon, Krypton and Radon.

But is seems a combination of halogens and noble gasses are used in 'halogen' lamps ...

Reply to
Andy Burns

am I correct in assuming that the "noble" ones can't cobmine with other elements to make an alloy?

Reply to
charles

At a "lies to schoolboys" level, yes ... you probably mean compound rather than alloy (which only applies to metals). In fact rather than never forming compounds with other elements, the noble gasses are merely "extremely unwilling" to do so.

Reply to
Andy Burns

They're otherwise known as the inert gases, so yes, they have trouble combining with other elements to form compounds. It has to do with them having a fully filled outer electron shell, according to my chemistry teacher in the 1970s.

There are a few interesting ones, though, mostly involving Flourine, which is *extremely* reactive.

formatting link

Reply to
John Williamson

i did debate with myself whether "alloy" was the right word to use. to me "compound" doesn't imply the same degree of combining.

Reply to
charles

Compound implies a much closer mingling and more interaction of elements than an alloy. Alloys tend to be microscopic grains of individual metals with little or no chemical interaction between them, while a chemical compound combines the elements on an atom by atom basis.

Reply to
John Williamson

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.