MR11 3.5mm Spots stopped working

[SLOPPY]

You need to find out if the transformer has packed up.

I've got a little bit further.

I've found the transformer (in picture)
The lights are on a chain of 4.
When I touch with my non contact voltage detector, the mains wire into the transformer, the output cable from the transformer, and all 4 wires going into each bulb voltage pen lights up suggesting there's power.

Do you think I still need to replace the transformer?

Many thanks in advance.

 

[Avo Mk8]

I've got a little bit further.

I've found the transformer (in picture)
The lights are on a chain of 4.
When I touch with my non contact voltage detector, the mains wire into the transformer, the output cable from the transformer, and all 4 wires going into each bulb voltage pen lights up suggesting there's power.

Do you think I still need to replace the transformer?

Many thanks in advance.

Reading what's written on the transformer, it seems to me likely that your new led bulbs do not add up to the minimum load that the transformer needs, namely 35watts. It's an electronic "transformer" specifically for halogen bulbs, so I think your choice is either to replace the bulbs with the halogen type, or buy a new 12V transformer suitable for driving your four LED bulbs.
But you really need a better method of testing than a volt stick, or someone to check this out for you. A multimeter would give a much better indication of what's going on, but in the meantime you could try replacing one led bulb with a halogen type and see if it all springs back to life!
The fact that your pen tester lights up on the wires going to the bulbs (from the SELV transformer) does possibly suggest a lost neutral to the supply? as has been mentioned before.

 

[SLOPPY]

Reading what's written on the transformer, it seems to me likely that your new led bulbs do not add up to the minimum load that the transformer needs, namely 35watts. It's an electronic "transformer" specifically for halogen bulbs, so I think your choice is either to replace the bulbs with the halogen type, or buy a new 12V transformer suitable for driving your four LED bulbs.
But you really need a better method of testing than a volt stick, or someone to check this out for you. A multimeter would give a much better indication of what's going on, but in the meantime you could try replacing one led bulb with a halogen type and see if it all springs back to life!
The fact that your pen tester lights up on the wires going to the bulbs (from the SELV transformer) does possibly suggest a lost neutral to the supply? as has been mentioned before.

I've now ordered a new transformer suitable for LEDs and some halogen bulbs just to test on the current transformer. They arrive tomorrow.

'Lost neutral' sounds interesting, but much beyond my minimal knowledge which amounts to wiring a plug and maybe a light fitting change.

I'll try the new halogen bulbs first, if no success, I'll swap the transformer to the new LED one using the LED bulbs.

If that doesn't work, like you say it's probably a lost neutral. In that situation I'll have to call in a professional.

I'm bit frustrated as I've taken the floating ceiling down and I didn't want this to beat me lol

I'll update on here tomorrow.

Thanks for your detailed reply. Very much appreciated.

 

[Avo Mk8]

'Lost neutral' sounds interesting,

It's just jargon meaning the blue (or black if old wiring!) neutral wire has become disconnected somewhere on its way from the supply to the transformer in the ceiling

 

[SLOPPY]

It's just jargon meaning the blue (or black if old wiring!) neutral wire has become disconnected somewhere on its way from the supply to the transformer in the ceiling

Wohooo they're working.

As I said in my previous post, I tried the new halogen bulbs first, unfortunately that didn't work.

Then I changed the transformer form the halogen transformer to the new LED supported transformer, then fitted the new LED MR11 bulbs and thankfully they worked.

I guess we can conclude that the halogen transformer was defective.

Now I've got the job of putting my floating ceiling back together, a job I learned I didn't need to do, as seen in the picture, it turns out the transformer was hidden above a hole in the original ceiling plasterboard between the loft insulation, I should have lifted that up when I first got in the loft. It's a bit of a chore putting it all back, but I'll do it with the biggest smile on my face.

Thanks to everybody who responded, I could not have done it without your help, I bow to your expertise.
I've leaned a few things, didn't know about transformers and the different types. It was a bit daunting, but it goes to show, you can achieve anything with a bit of patience, confidence and some good advice.

Thanks again very much appreciated.

David

 

[Avo Mk8]

Wohooo they're working.

Well done
Your perseverance paid off!
Thanks for letting us know - not everyone comes back to confirm a problem is sorted, and it's nice to hear!

 

[brianmoooore]

Before you put it all back together, there are covers missing off of that driver, and it is a requirement that the grey sheath of the mains cable enters under that cover, with none of the brown or blue wires outside of it.
As it is, it merits a C2 "unsatisfactory", or even a C1 "unsatisfactory", depending on how exposed the live terminals are, if discovered by someone carrying out an EICR on the property.

 

[SLOPPY]

Before you put it all back together, there are covers missing off of that driver, and it is a requirement that the grey sheath of the mains cable enters under that cover, with none of the brown or blue wires outside of it.
As it is, it merits a C2 "unsatisfactory", or even a C1 "unsatisfactory", depending on how exposed the live terminals are, if discovered by someone carrying out an EICR on the property.

Hi,

I put the ceiling back together and it wasn't until then when I realised I had not put said covers back on the exposed wires you mention, I found the covers on my bed with the screws later. Luckly, I now know I can access my new transformer from the loft through the hole in the original ceiling. I intend to put them back on tomorrow on my day off, I'm worried it may cause a fire being near the loft insulation.

Many thanks for pointing that out and well spotted.

David