SWA questions, doubting electrician

[LeeH38]

Recently had an electrician in to wire up power to a detached garage and also wire in a 32 amp rotary switch for an eventual hot tub install.

He has used a spare 40amp MCB in the house consumer for the garage and a 32amp one for the hot tub point. Cable run for both is about 10m each.

He left on Friday and the whole side of the consumer in the house tripped immediately and I started having doubts about other things then as part of the kitchen is also on that side of the consumer and hasn’t been touched. I then switched the two new circuits off and the consumer continues to trip whenever I plug anything in in the kitchen. Been promised a visit to sort it out but today I simply removed the new wiring into the consumer to see if I could get the kitchen back up as it’s a nightmare without and everything has returned to normal.

Now having major doubts about the rest of the work and have had another opinion from a retired electrician neighbour and it doesn’t look good. However original installer is saying it’s something simple and everything has been done to standard.

My main doubts are:

1. Is 4mm armoured cable sufficient for this layout. I have a 32 and 6 amp MCB on another board in the garage run from the 40amp MCB on the house board. This is to run 8 sockets and 4 led lights.
2. Is 4mm armoured cable sufficient for a hot tub. I am led to believe it should be 6mm.
3. Non of the armour part of the cable is earthed, he reckons it’s fine as it’s 3 core and earth is inside. I don’t believe this though and think it needs earthing at the house consumer at the very least.

I am struggling to have a reasoned discussion as he is the electrician and I’m reading stuff on the internet, I wouldn’t have even started searching had I not had the initial issues.

Meant to be inspected and a certificate off someone else this week but not sure that means much tbh?

Any advice on how to approach this very much appreciated.

Thanks,

Lee

 

[LeeH38]

I take it that's under the consumer unit? If so I very much doubt it will reach to redo this with a correct gland & banjo without either renewing it or a join or isolator of some kind.

It is. There is some excess cable under the kitchen units in the next room.

 

[ipf]

I take it that's under the consumer unit? If so I very much doubt it will reach unless there's an amount of slack to redo this with a correct gland & banjo without either renewing it or a join or isolator of some kind.

I wouldn't be glanding with banjos (or earthing nut) in that plastic CU, anyway. It requires a metal adaptable box fitting below the unit. Swa glands in plastic.....horrible!

 

[James]

I wouldn't be glanding with banjos (or earthing nut) in that plastic CU, anyway. It requires a metal adaptable box fitting below the unit. Swa glands in plastic.....horrible!

"REQUIRES" is a strong word.
I would prefer to make off into a metal enclosure but if the cable is supported correctly, a plastic enclosure can be glanded off correctly with either a banjo or earthing nut.

 

[davesparks]

I wouldn't be glanding with banjos (or earthing nut) in that plastic CU, anyway. It requires a metal adaptable box fitting below the unit. Swa glands in plastic.....horrible!

A steel through box is another good option, it has an earth terminal in it already to make the connection to the armour nice and easy.

 

[ipf]

"REQUIRES" is a strong word.
I would prefer to make off into a metal enclosure but if the cable is supported correctly, a plastic enclosure can be glanded off correctly with either a banjo or earthing nut.

Depends how you take it...in my view it does require it, taking into account those flimsy plastic units.

 

[James]

A well supported swa cable, adds no strain to the enclosure. In some ways it makes it more rigid.

 

[telectrix]

in the OP's case, the installer has cut big holes in bottom of CU, so a through box is required here. 1. to gland the SWA, and 2. to restore the IP rating of the CU.