12v downlighter - a bit of a mystery to me!

[theflyingpig]

Hi All,

My mate got me to have a look at his bathroom downlighters tht was working for the first few seconds after turned on, but would then go out. I pulled out the bulb and holder and could see what I assumed was a transfomer through the whole. It had Aorora 50 W 12V written on t, so after a post on here I bought a new one - assuming that each downlighter had its own transformer.
Over the weekend I finally got around to trying to install the new part, but when I removed the entire light assembly to access wiring I saw that what I had been looking at was not a transformer at all! It was just an L shaped bracked witha connecting block in it. Two wires (both black) going into one side of bloack, and two wires from other side to bulb.
So I'm a bit confused!
I assume this means that each downlighter does NOT have its own transformer, but whats with the L shaped bracket? The connecting block does look as if there has been some heat there . . . should I just replace the connecting block and hope for the best?

thanks for any ideas!

Huey

 

[Dartlec]

Huey,

The bracket you mention is designed to hold the terminal block away from the heat produced by the light to avoid damage to the cabling, but as you have discovered some of the designs are rather poor and do not stay in place once installed.

One transformer may be providing the supply for just this light, or some or all of the lights.

The best first step is to try replacing the connector block and see if the light then works. Check the existing cables for heat damage as you do this and replace as necessary. If that doesn't work then you will need to locate the transformer to test/replace it. Naughty installers do not always make sure the transformer is accessible from below so it may or may not be easy to achieve.

Hope that Helps

 

[theflyingpig]

many thanks - that explains the bracket! will give it a go and fingers crossed as it certainly looks like there is no access to the transformer. . thanks again.

Huey

 

[RF Lighting]

It could also be a failed lampholder.

 

[theflyingpig]

hi, could you explain the failed lightholder please? it doesn't earth against this does it?

thanks

 

[RF Lighting]

Sometimes heat can damage the lampholder where it connects to the lamp pins.

This often allows the lamp to light initially, but it extinguishes as the contacts heat up and expand when the light is switched on, resulting in the lamp loosing its connection to the lampholder.

 

[theflyingpig]

thanks - it looked like the bulb as attached directly to the wiring with a small white circular plug - that is, the pins on the bulb pushed into one side of this 'plug' and the wires from the connecting block into the other side - it is this little white plug thingy you mean?

thanks again!

 

[RF Lighting]

Yep. There are two sprung contacts in the little white ceramic jobbie which connect to the pins on the back of the lamp.

 

[theflyingpig]

great - Will replace the connecting blockand the ceramic jobby and see what happens. cheers!

 

[RF Lighting]

If there is any sign of charring / burning / pitting on the lamp pins, then I'd advise you replace the lamp aswell to avoid any damage to the new lampholder