Help with Spotlight problem please!

[Tigerpig]

Hi everyone, really hoping someone can help?

We are trying to swap the spot lights in our living room. It's a new house to us and the previous owner had installed halogen spot lights (GU5.3 bulbs) they were a bit of a mess so we decided to buy new spot lights and LED bulbs (GU10)

So new spotlights wired in (really straight forward choc box wiring) but they don't work?!

Put a couple of the old spot lights back up and they work?

Tried different bulbs, double checking the wiring is correct (Neutral to neutral and live to live) and now we are stumped

The halogen lights we took down had two white wires versus a live and neutral as I would expect.

My DH then wired one of the new spotlights on to the wall light wiring to check and they work so we think it might be something to do with the ceiling circuit- but what?

Help!!

We've recently converted three rooms to LED lighting - not without some hiccups. It might be the transformers because the LEDs don't use a lot of power. Have a look online, there's lots of info on there. If you have a dimmer switch it has to be compatible with LED lighting. It'll either be called an LED dimmer (catchy) or a trailing edge dimmer.

Thanks wowfudge

I've checked the bulbs we took down and they are 12v...whereas the new fittings/bulbs are 220v

Given this new development I expect you are right and it's something to do with a transformer.

DH is trying to look in the spotlight holes now to see if he can find the transformer(s)

This was supposed to be a 10 minute job

Oh it's usually the way, takes longer than you imagine. Would there be any access to transformer through floor boards in bedrooms.

Might have been easier just to retrofit LED bulbs. Bloody LED compatible dimmers lost me a couple of hours of my life poring over a Screwfix catalogue last week.

Sorted! Was the transformers after all.

Thanks for your help. It's amazing how much you learn when doing up a house

A word of caution. If a single transformer is feeding multiple lamps (or indeed 1:1 but some distance away) be careful to ensure that the cable that you use is suitable for mains voltage and has an earth. Typically 12 wiring will be of a heavy gauge due to the high current/volt drop but may have no earth core.

Thanks engineers

The wire appears to be heavy duty. Grey outer wire sleeve, and a solid 'core' to each of the wires inside it. Does that sound about right?

Is it twin and earth (oval smooth jacket containing 2 separately insulated conductors plus an uninsulated earth conductor) or two insulated cores joined together looking like a figure 8?

It's like the second one. No earth wire going into spotlights.

That cable is very unlikely to be suitable. The two issues are:
Insulation, there is in outer sheath/scuff jacket.
Lack of an earth, most fittings still require an earth due to exposed metal fittings, some integrated units don't but depends upon the unit.
Sounds like you should get an electrician just to take a look, they'll estimate for free so if nothing needs changing it shouldn't cost anything.

Agreed with the above, you need to run an earth everywhere even if it's not used at present, and all cables need insulation suitable for the voltage, need to be 1mm² or more, and have either a protective sheath or be in conduit. They also need to be identified at their termination points ie brown/blue insulation.

Thank you engineer and johnd2

The inner wire insulation colours are red and black which I believe are the old live and neutral colours. Definitely no earth wire. The choc box is mounted inside a black plastic box for each spot light.

I will get an electrician out to be on the safe side.

Appreciate everyone taking the time to respond.

This is a new house to us (6 weeks in now) and our to do list is ever expanding!!