Transformer question

[chem]

Hi All,

I have a question regarding a low voltage transformer and stair lights.

I've purchased this transformer: http://www.tlc-direct.co.uk/Products/LTYT150.html (technical spec: http://www.tlc-direct.co.uk/Technical/DataSheets/Systems/Transformers.htm - see LTYT150)

I've also purchased 7 small wall lights each with a 10w (12v) G4 bulb - the light fitment can take a 20w max.

With the transformer I have very limited access to the stairs and now that i've brought it home I've noticed on the instructions that for the 3 outputs from the transformer you should only have 1 light optimum distance of 30cm.

I was hoping to wire it like this - hope you can view this:

[code:1]

output1
in |-------|-------|
| O O
-----| |-------|-------|
transformer
-----| |-------|-------|-------|-------|-------|
| O O O O O
|-------|-------|-------|-------|-------|
output2

[/code:1]

The 2 lights on output 1 are at the bottom of the stairs and the 5 lights on output 2 will run the length of the stairs. The cable distance between each light is 120cm.

I've set the lights up on the floor with the correct cable runs to test this and they have been running for an hour with no problems, the transformer is warm but seems to be running fine.

I've used 1.5mm cable between all of the lights as i've read about voltage drop over long runs if the cable is too thin - in the test all lights look exactly the same, there is no dimming of the light.

The transformer is rated for 150w and I am using just 70w, the transformer output voltage is stated at 11.5V max 12.5A.

My question is really just to confirm that what I am doing here is ok - I haven't exceeded the wattage but don't want to go to all the trouble of chasing the walls out to find that I can't do what I need here. The transformer will be placed in a space under the stairs with easy access and a lot of room to keep cool.

Any advice would be appreciated.

Thanks, Chris.

 

[RF Lighting]

I hope you don't have any children in your house ever.

They will give them selves second degree burns off those fittings.

Come to think of it so will your toes if you are barefoot and catch one of the fittings.

 

[briwire]

You're supposed to keep the cable short because of the volt drop. If you can connect say, 1.5 to each fitting and run them all back to a single connection in a convenient place, that would be better than daisy-chaining several fittings, as the first ones in the chain would be carrying the whole current.

Theres no danger of overheating, only that if the run was too long, the light would be dim.

 

[Steve]

RF's right - they are halogen lights, which by their very nature get very hot.

 

[RF Lighting]

Burns hurt. Trust me on that

 

[breezer]

mighht be something like

 

[chem]

thanks for the responses.
breezer your right, they are just like that, wall mounted to the side of the stairs.
from the esponse it looks like it would be best to run individual cables back to the transformer rather than chain the light together.