Minor electric shock with the power off... faulty circuit breaker?

[terryplumb]

Yes, that slinky black number

 

[john4703]

Are there any fluorescent fittings on the circuit? They can have capacitors that can give a nasty shock as they discharge.

 

[crystal ball]

I think that additional CU needs checking, tails stuffed in the live side of the other CU main switch maybe?

 

[JohnW2]

I think that additional CU needs checking, tails stuffed in the live side of the other CU main switch maybe?

They could be, but that wouldn't make anything live on a lighting circuit if, as we've been told the secondary CU only feeds a shower (which sounds pretty credible).

Kind Regards, John

 

[RF Lighting]

Bathroom refurb. Shower and lighting wired into a separate 2 way board to provide RCD protection.

 

[JohnW2]

Bathroom refurb. Shower and lighting wired into a separate 2 way board to provide RCD protection.

I thought of that, but more-or-less dismissed the possibility because of ...

I then went to change a standard light switch in an upstairs bedroom. .... I brushed the tip of one of the red wires with my hand and got an electric shock.

It might not even have been a lighting circuit, but I decided that it was very unlikely that it would be fed from a circuit created during a bathroom refurb.

However, having said that, as we learn only too often, almost nothing is 'impossible'

Kind Regards, John

 

[SUNRAY]

What I'm thinking is: Bathroom fitters, electric shower, move whole of upstairs lighting to new CU which includes RCD.

 

[MagMrMax]

Hi Everyone

Thanks for all chipping in. Apologies, too, for the blurriness of some of these photos.

1. So, here's the upstairs landing. The previously mentioned shower is in the bathroom on the left,
the airing cupboard is in the centre-right, and the light switch I was shocked by is visible on the far right.

2. Here, the airing cupboard door is open, end on to us. Visible is the isolator switch and trunking for the shower.

3. Into the garage now, here's the original circuit breaker on the left, the newer one for the shower on the right, and the newer trunking.

4. Original breaker. All of these switches were 100% definitely off when I was shocked.

5. Newer breaker. To my knowledge, this was fitted to supply the shower only. All of these switches were on when I was shocked,
because I thought that I had basically turned the power to the house off by turning off the main breaker system
(e.g. all the lights were off, all the TVs, etc., weren't showing any lights, and so on).

Thanks

 

[crystal ball]

Looks like the tails for shower CU are heading into the wall, can you take a pic of your meter arrangements

Also theres a 6amp MCB hmmm the plot thickens

 

[MagMrMax]

Just looking back at the queries, there are no fluorescent fittings in the bedroom.

Here's the meter. It's immediately behind the 2 CUs on the exterior wall (the 2 CUs being on the inside of the garage wall).

Thanks

 

[SUNRAY]

I'll lay a bet in the short piece of trunking just above the CU's is a small T&E 1 or 1.5mm²

 

[SUNRAY]

Just looking back at the queries, there are no fluorescent fittings in the bedroom.

Here's the meter. It's immediately behind the CU on the exterior wall (the CU being on the inside of the garage wall).

Thanks

View attachment 215547 View attachment 215548

just as predicted by many on here.

 

[crystal ball]

To get around the need for bonding in the bathroom the shower guy has moved the upstairs lights to the RCD protected circuit in the 2 way, did it trip out when you had your shock?

 

[foxhole]

Did you use tester on live and neutral, got a shock once with power off , live and neutral had been reversed.

 

[MagMrMax]

To get around the need for bonding in the bathroom the shower guy has moved the upstairs lights to the RCD protected circuit in the 2 way, did it trip out when you had your shock?

I'm sorry, but I couldn't say. [Update: I have just re-read this. No, the switches in the small newer circuit breaker didn't trip.]

I had the old light switch physically detached from the wall when I was shocked.

Warily (naively), I then used insulated pliers to individually grip the 1 Earth and 2 live red wires (only the sheathing, of course), twisted them as I needed them, and re-attached them to the new switch.

I then left that unsecured (hanging off the wall), went back to the garage, switched all the breakers in the main CU back on, and returned upstairs. On switching the bedroom light on at that point, it worked.