Shed Consumer Unit no power

Joined
30 Nov 2019
Messages
21
Reaction score
3
Country
United Kingdom
Two years ago I had a consumer unit fitted in the shed to supply a LED bulk head light and double socket. In the consumer unit I have three switches: one for socket, one for light and the main switch. I wanted to change the light and when wiring it up (with all power off of course) I made a mistake and when I switched the power back on and flicked the light switch some or all switches in the CU tripped (stupidly I did not pay particular attention to which ones or if all of them tripped). I rewired and wanted to test it all again, but now I had no power to the socket or the light (even though I did not change anything in the socket set up). I found that an MCB on the consumer unit in the house had tripped and I reset it hoping that was the solution, but I still had no power. I was then worried that the MCB broke/had blown and I replaced it today, but still no power. What else can I try? Could both circuit breakers in the shed have broken/blown? Is it worth a try changing those?

Any help/advice would be great! Thanks in advance.
 
Did the mcb in the house trip again after resetting it and turning on the light switch in the shed?

Blup
 
Thanks for replying!

No it did not trip again.
 
Maybe the replacement mcb hasn't been fitted correctly on the main CU.

Blup
 
Could both circuit breakers in the shed have broken/blown?
That is so unlikely as to be near impossible.

What testing equipment have you got - as the first thing is to determine where there is power, or not.
Randomly swapping items is not a solution to anything.
 
This is what I did: it is a Hager MTN132, I opened the screws at top and bottom fully , pulled down the little clip at the back/bottom. Removed the old MCB, pushed the new on on the busbar, pushed little clip at back upwards, tightened bottom screw. Inserted brown wire into top and tightened screw. Does that sound right to you or do you spot a mistake in my description?

Thanks
 
That is so unlikely as to be near impossible.

What testing equipment have you got - as the first thing is to determine where there is power, or not.
Randomly swapping items is not a solution to anything.
What testing equipment have you got - as the first thing is to determine where there is power, or not.
Randomly swapping items is not a solution to anything.
I have got a cheap/amateur multimeter and not a lot of experience using it, but I am always keen to learn new skills. Can you give me some hints? what am I looking for?
 
We could do with photos of inside of the garage cu, the light you wired up, and the cu in the house if it's easy to do.
 
[GALLERY=media, 105467]IMG_3236 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY][GALLERY=media, 105468]IMG_3237 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY][GALLERY=media, 105469]IMG_3238 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY][GALLERY=media, 105470]IMG_3244 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY][GALLERY=media, 105471]IMG_3246 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY][GALLERY=media, 105472]IMG_3249 by Em01 posted 7 Nov 2020 at 5:20 PM[/GALLERY]

The power to the light goes through a junction box because we had an outside light connected there (and there might be one again in the future if the replacement solar one does not charge enough over the winter.)
 
I guess I would test the cables going into the shed CU to determine if any power arrives there?
That would be a start. Check the MCB that you fitted first
 
Last edited:
ok I have just used the multimeter on the consumer unit in the shed. No power is coming into there. I checked the multimeter was working by testing it on a socket outlet in the house. But now what? What could I have done wrong when changing the MCB? What is that little clip at the back for? Everything else seemed pretty straight forward to me.
 
You need to check the MCB at house . Correctly clamped onto the bus bar ,and voltage ok at the top together with the conductor correctly clamped into top terminal.
 
Back
Top