Not DIY advice. How often do pros work live?

[aesmith]

First off there is no question of me doing anything live. Or even near anything live.

This is just a question triggered by observing they guys installing our solar. They did everything live, including installing a new RCBO in the garage consumer unit and connecting the new circuit. None of our electrics were switched off at any stage.

When I mentioned this they said they do this all the time.

Is this normal? As a non-electrician I can't see why they wouldn't at least switch off the main switch on the CU. (I'd have shut off the isolator at the house so nothing in the CU was live)

The only other possibly relevant point is I asked them at the start when they were likely to shut power off, as I was set up ready to power the chick shed from a generator but didn’t want to have to run that all day. Possibly the were responding to that.

 

[littlespark]

It is drilled into all of us during training that there should be no live work whatsoever.

If the power has to go off, it has to go off... no if's, but's, or maybe's

You were already prepared for a generator, and i wouldnt see it being off for more than an hour anyway.
They had no good reason to work live.

We are permitted to test live... ie insert test prongs into a connector... but that is it.



There is additional training for working live, which needs additional PPE, risk assessments, for the extra danger... but i doubt a couple of solar guys had little more than a pair of flash sunglasses as PPE

Most companies frown upon working live..... for insurance purposes more than anything.



I think ive got my point across.

 

[aesmith]

I think ive got my point across.

You have, more or less what I would have expected. Without badmouthing the guys too much, as far as I can tell the work was all done to a decent standard and certainly neat, but I wonder if there was an element of showing off.

 

[littlespark]

certainly showing off....

They'd think twice if a customer saw them actually getting a shock, or creating a bang with a careless screwdriver drop

 

[Dan]

If they (or any person) did get a shock and for a second became a connection where one shouldn't be, would it cause any issues round the circuit? Maybe something having too much power running through it after it's been reduced or whatever the term is.

Asking for a friend

 

[littlespark]

Come on, @Dan , i'm sure youve picked up enough from us professionals to know


In the OP's case, if theyve been poking about in a consumer unit, they may not have had the benefit of any RCD protection if theyve been on the supply side.... Nothing but the main supplier fuse, which, in reality doesnt give much protection at all.... It really has to be a dead short between live and neutral or earth for it to blow it instantly.

An RCD doesnt reduce the size of electric shock, just the duration.... and thats only if they're working properly.

 

[aesmith]

In the OP's case, if theyve been poking about in a consumer unit, they may not have had the benefit of any RCD protection if theyve been on the supply side...

That's correct in this case, no RCD upstream of the garage CU, only a fused isolator in the house. I actually can't even think how you'd wrangle a new RCBO onto the live bus bar without disturbing the other circuits.

(It's an RCBO board and the original electrician said we don't need upstream RCD since it's armoured cable the full length)

 

[littlespark]

That's correct in this case, no RCD upstream of the garage CU, only a fused isolator in the house. I actually can't even think how you'd wrangle a new RCBO onto the live bus bar without disturbing the other circuits.

(It's an RCBO board and the original electrician said we don't need upstream RCD since it's armoured cable the full length)

Thats right.... The cable and installation method doesnt warrant having an RCD, if the outgoing final circuits are covered....

However their "showing off" or just laziness to not isolate the board they were working on doesnt make them appear very professional

 

[aesmith]

Thats right.... The cable and installation method doesnt warrant having an RCD, if the outgoing final circuits are covered....

Thanks, I was reasonably confident but nice to confirm. That was the original install getting power to the outbuilding, done by an electrician we engaged ourselves quite a few years ago.