And there was light!... for a short time.

[eyedee]

A ceiling light was fitted in my upstairs landing about a year ago. It was sold by B&Q (Domus I think it was called) and it has 8 x 10W LEDs that are attached to the bottom of 8 wires that hang from the metal circular enclosure that is fitted to the ceiling. The light came supplied with a round 35-105W/VA transformer and it worked without fault for about 6 months, then it suddenly started dimming randomly until it finally wouldn't turn on at all (so I'm assuming the transformer blew). It was out of guarantee as it wasn't fitted as soon as it was purchased.

I checked the light all over and couldn't see any problems. The bulbs were all correct and the wiring all in place and without any obvious fault. So I went and bought a replacement HALOLITE 35-105W/VA rectangular transformer (which fit inside the light casing perfectly) from screwfix and the light was working perfectly again... for about 3 months. Now it's started dimming and turning itself off randomly. Sometimes it will work for 15 minutes and sometimes it will illuminate for 1 second before it goes dark or dims. I'm only guessing that this is due to the transformers overload protection, but why would it be overloading when it is only outputting 80W and the transformer is capable of up to 105W? The transformer also has Short-Circuit and Thermal Protection.

I have checked the lighting circuit and there doesn't seem to be any problems with it that are obvious. The other 4 upstairs rooms lighting do not dim or have any problems whatsoever so I am sure it's just to do with this light. I could go and buy a new one, but I am very curious to know what the problem is and if it can be permanently fixed, or if it is the light that is duff then what's wrong with it?

Thoughts would be much appreciated. Cheers

 

[Steve]

For starters, they are not LEDs.

A 10w LED would be a turn up for the books.

What you have is those dreadfully inefficient halogen capsules.

Anyway, is it possible someone has fitted the wrong wattage capsules? Check them, they should say their wattage on the flat part near the base.

 

[eyedee]

Thanks for the fast reply.

Doh! Yes, sorry. I'm always calling them LED's! All 8 are definitely 10W halogen capsules. I just double checked them. Could it be possible one of the halogen capsules is causing the problem, even if it the correct wattage? Or could the light unit (metal casing, metal hanging wires) have a fault that would cause the problem? It's got me truly baffled!

 

[Steve]

A few possibilities:

1. The transformer is overheating. This is quite common with new light fitings with tight space for the tx to sit in, and no ventilation. Also remember the ceiling is the hottest part of the room.

2. The Tx is overloaded. Like i said, the way to check this is to check each lamp for its wattage.

3. The Tx is faulty.

It does sound like the Tx is trying to protect itself though, they have a built in protection that shuts them down if any of the above happens. Though with the price of new ones, it wont be a huge hardship to buy a new one if you cant find the fault.

If you think the Tx is overheating, try installing it away from the light fitting itself - simply extend the ELV wires up into the ceiling space, and fit the Tx there.

 

[eyedee]

I seriously doubt the transformer is overheating. My house is very cold at the moment (no heating at all due to refurbishment) and no insulation (it really is like a fridge) and the bulbs dim and then go out completely within 2 seconds of the light being turned on having not been turned on for days.

I will triple check the wattages of the bulbs, but as I said, I have double checked them previously and they were all 10W as they should be.

As I said in my first post, I have already purchased and installed a new TX so I'm 99% sure thats not the problem.

I can only think the problem is with the manufacture of the light itself. But then why would it work perfectly for months before starting to go wrong using both the original transformer and then the replacement TX.

Maybe the transformers did overhear WHILST they were initially working properly and became damaged which is now causing them to make the lights dim and go off after a couple of seconds. All I can think of trying is getting another new TX and fitting it in the loft. If that doesn't fix it it must be something to do with the light unit itself and I'll have to buy another.

I hope I can get it working properly as I love the look of the light.

 

[RF Lighting]

It might bea loose connection somewhere on the circuit.

 

[jj4091]

If you have only had the transformer for 3 months call screw fix & ask for a replacement under warranty, I have always found them to be excellent for after sales service.

 

[aptsys]

A 10w LED would be a turn up for the books.

They're readily available. Have a look through RS and Farnell...

 

[eyedee]

I've checked the circuit and I can't see a fault. I'll try and get a replacement TX from screwfix and install it in the loft. If that doesn't work I think I'll give up and admit defeat.

Cheers