changing transformer

[sjmyles]

I have a light fitting consisting of 7 x 10w halogen bulbs.
The fitting has a transformer though I no not what sort but it is NOT dimmable. This is my problem I'd like it dimmable so I'm going to change it if i can but the type of transformer i need is confusing.
I need one thats takes over 70w but how about the number of outs from the transformer. Do i need 7 and wire each bulb to one or can i use a transformer with one out and wire all into this. I think at present all 7 are bundled into the transformer within the light fitting.

 

[Kimba]

Tansformers tend to only have one outlet, which will be made of cable rated at over the maximum supply current of the transformer. Therefore providing the transfer is above the minimum you require for the number of lamps you are going to connect, you can just wire them all in parrell to the transformer's output.

 

[breezer]

Tansformers tend to only have one outlet,

sorry to disagree, i have some that have 6 terminals (3 for each) yes its omne "outlet" but that's not what poster meant, although i agree with your answer

 

[Kimba]

Ah perhaps I misunderstood sjmyles. It is entirely possible that the outlet of the transfer is effectively connected to two stips of choc-block, giving the impression of multiple outlets, but this is really only for convenience of the installer, and doesn't indicate how many lamps the transfer can necessary power, for that you still need to refer to the transformers output rating, and the power of the lamps being used.

 

[ban-all-sheds]

And bear in mind that some of the cheaper transformers use a crude form of output voltage regulation that expects the full load, or thereabouts, to be present. If you have multiple bulbs making up the load, and one blows, the output voltage goes up a bit, hastening the demise of the next flakiest bulb and another ramping up of the output. Before long the remaining bulbs start failing quickly.

1) If possible use 1 transformer per light

2) If not, use a good one (don't buy it from a shed)

3) If you have multiple bulbs, and one blows, replace it pronto.