Need help wiring a transformer

[Yenoom]

I have brought this light set which came with a transformer that you were meant to wire up.

I took down the old light and disconected all the wiring, probably my first mistake not noting where they went. Out of the Celing came three wires each had a red one a black one and a green one. I then connected all red wires together, assuming they were all live, and all the black, and earth wires togethers.

I then connected it up to my transformer, turned the power to the lights back on flipped the switch and blew the MCB (i think - sounded like i did). Though this could have been because i hadn't properly insulated the wires on the other side of the transformer and got a short circuit, or i messed up the wiring. Also the actual light was not connected to the transformer at the time, I hoped to connect up a current meter and check it was working before attaching the light.

I am not entirely sure what I have done wrong, if anyone could help i would really appreciate it. I have looked at other posts on this forum, though none seem to directly relate to this problem.

Thank you.

 

[Big_Spark]

It never ceases to amaze me how many first time posters start with

took down the old light and disconected all the wiring, probably my first mistake not noting where they went

If you don't have the common sense to do this, then with respect, you don't have the knowledge to do the job in the first place.

It is better to ask first and sound like a fool, than go blindly ahead and prove it!!

You have three cables, Feed In, Feed Out and a switch pair.

Identify the switch pair (a black and red), The BLACK IS NOT A NEUTRAL IN THIS CABLE. In order to identify this, connect a multimeter across the a black and red pair from each cable, and then operate the switch, the needle will move as you do this. This is the switch pair. MARK THE BLACK WITH RED TAPE

Now back at your Transformer.

ALL the REDS go together.

The BLACK from the Switched pair (The one marked with red tape) and connect this with the brown or live of the transformer.

The remaining TWO blacks are NEUTRALS, these need to connect to the BLUE or Neutral of the transformer.

The Earth cores, which should be sleeved in Green/Yellow sleeving, MUST be connected together. DO NOT CONNECT ANY OF THEM TO THE TRANSFORMER UNDER ANY CIRCUMSTANCES.

When, AND ONLY WHEN, you have done the above, turn the power back on to that circuit, your lights will now work...IF you have not blown the living crap out of the transformer!!

Perhaps in future you will seek advice before attempting to kill yourself or blow something up!

 

[Yenoom]

Thank you very much for your help. Point taken.

I have done all of the above, though the light still does not work when i flip the switch, should i do something with the red wires, apart from group them together or just leave them behind?

Thank You.

 

[Big_Spark]

Yenoom, I hope you have connected them together in some way to form an electrical connection.


What you need to do now is take your multimeter again, and check that you have 230V going into the transformer when the switch is in the on position, if you have, check to see you have 12V coming out the other side.

If you have 12V, you blew the lamps, if you don't have 12V, you blew the transformer!

If you don't have 230V, check your connections, and check to make sure you turned the breaker back on..sounds daft..you'd be surprised at how easy it is to forget that bit..even for a spark!!