300va wiring PLEASE HELP!!!!

[bexxxxx]

The wiring is in the roof - the only way to get at it to add more or adjust is to take the roof off!

This is our main lighting system upstairs (the only lighting for our hallway) so obviously if it isn't up to the job I have a BIG problem!

 

[RossR]

How is the cable installed? e.g. clipped to wooden beams, or buried in plaster?

 

[bexxxxx]

It's under the tiles with the insulation

 

[RossR]

If it's in contact with thermal insulation then it is under rated for the current it will be carrying and is a fire risk.

 

[bexxxxx]

That was my concern

 

[bexxxxx]

My sparky doesn't seem to know what he is doing - he has just finished first fix.

If I ask him anything regarding my concerns he basically tells me I don't know what I'm talking about - ie. he's the sparky and I shouldn't be questioning him!

Can I get a different sparky in to do second fix - have to get certificate somehow?

 

[bernardgreen]

What sort of lamps are used in the fitting ? And is it a real transformer ( wound coils ) or an electronic "transformer" ( switched mode power supply )

Low voltage will shorten life of halogen lamps and some high power electronic "transformers" can automatically and continuously compensate for the voltage drop along the high current feed to the lamps.

To do this they use sensing input that measures the voltage at the fitting. If the transformer has this function it will require one ( sometimes 2 ) extra wires ( low current ) from the fitting to the "transformer's" sense input.

Too often these are installed with the sense input linked to output at the "transformer" and not at the fitting so the compensation for voltage drop along the cable cannot happen.

 

[RossR]

Really, the solution is to move the transformer to be right next to one end of the 2-wire system. I know it's not what was specified, but it's how it's got to be done.

 

[stillp]

Or rethink the lamps you were planning to use, perhaps by using something more efficient than your proposed 6 X 50W or 8 X 35 W.

 

[bexxxxx]

If I rethink the lamps - i'm not gonna get much from 2.5mm am I?

I think redoing it so the transformer is next to the fitting is the best solution but my sparky will charge me extra for changing it!

Regarding second fix- can I use a different sparky and can he sign off sparky #1's work?

 

[RossR]

You could get say 8 X 6W LEDs. The good ones don't come cheap though.

And no - A new electrician can't sign off the first guys work.

 

[bexxxxx]

So am I stuck with a rubbish sparky? No choice?

 

[ban-all-sheds]

He was supposed to put 6mm wire in for the 300va transformer and has only put in 4mm and now the roofs gone back on and I can't change it without taking the roof off!

And now he's taken out the 4mm² and put in 2.5mm²?

Whatever, it seems like the job was properly specced in the first place, he decided to do it not to spec because he thought he knew better, it turned out he was an incompetent ***t who did not know better and has now landed you with a dangerous and/or inoperative lighting installation.

Not only do you need to get a proper electrician in to resolve the mess and finish it off properly, you need to tell the incompetent ***t that not only will you not be paying him you'll be coming after him for the extra costs you'll be incurring as a result of his incompetence and failure to do the job as specified.

 

[bexxxxx]

Different part of the house- for some reason he's put 4mm in one area and then 2.5mm in another - both are for the same type of light fitting???

Not sure why he's done this - only noticed the 2.5mm yesterday!

He has rewired the whole house and it has now been re plastered - I have UFH going in next week which will cover up all the remaining cables. It will be very difficult for a new sparky to see what he has done!

I am concerned that he doesn't know what he's doing and that fixing it with a new sparky is going to cost me a fortune!

 

[bexxxxx]

Is it possible to notify BC at this stage and do second fix myself?