12V (low voltage) lighting problem - one light goes off!

[fathertobe]

I have two low voltage lights in one of the rooms in my house. After a short period of time on, one of the lights (the same one each time) switches off.

Sometimes it comes back on again a while later, sometimes not. It's almost as if it's wired into a swtich in someone else's house. It's not. But such is it's behaviour that it feels as if it's beeing independently controlled.

No doubt a problem with the transformer but anyone else seen this problem. I seem to remember that we had the same thing with some lights in our first house some years ago. But I didn't have the confidence/interest to investigate the problem then ...

BTW, the lights are on dimmers.

 

[EddieCurrent]

Hello,

The transformers you have may have a thermal cut-outs.

Does the light always come on, and stay on for a while first, before going out ?

 

[fathertobe]

Yes, always on at the start.

This makes sense. Does it mean that if I lowered the wattage - currently 50W - down to 35W bulbs - it might help?

Thanks for a prompt reply!

 

[Taylortwocities]

Are both lights on one transformer or do they have a transformer each?

it may be the transformer crowbarring out or it could aimply be a bad connection on the 12v side. Look carefully at all the connections and make sure the lamp connection is not scrogged (that's an actual electrician's term - its in the regs!)

TTC

 

[fathertobe]

They have one each. I've yanked out the transformers on the misbehaving light and can't see anything obviously dodgy. But in the light I will remove cables and reexpose wire from the sheath to make sure it's not this.

In the meantime, I've dropped the bulb from 50W to 35W as its intermittent nature does suggest some kind of thermal drop out - ie it gets hot, cuts out - then when cool, comes back on again.

Feel free to comment. Will post solution when I'm there. Couldn't find any similar posts, though - and I'm sure there must be some!

Many thanks again.

 

[RF Lighting]

I bet you a kit kat that replacing the 12V lampholder will cure the problem.

When you first switch the light on the lampholder contacts are cold. once it has been on for a while the contacts heat up and expand, causing the lamp to go off.

http://www.tlc-direct.co.uk/Products/BGLVLH.html

 

[fathertobe]

You're on! But could we go with something other than a Kit-Kat? I try to avoid Nestle for reasons that are inappropriate to explain here(!)

Thanks for this, though. It does seem an incredibly plausible explanation. I'm going to get some asap.

 

[RF Lighting]

A crunchie then.

My sister is the same with nestle

 

[fathertobe]

Respec' to your sis! Have just ordered the cables.