Cut busbar & cable used to connect breaker

[Wooglepoops]

Hey Guys,
So I was in a consumer unit today to find the previous electrician hadn't had the required Breaker for the consumer unit.
It was a 20A pv job run in 4mm to the top of the 20A Breaker,
Then the busbar had been removed from the underneath so it would fit and another piece of 4mm connected to the underside of another Breaker with the busbar.
Obviously it's rough, but without installing a new busbar (if I can find one for this oldish board) or a new smaller garage unit there's nothing more I can do.
What are the risks of leaving it like this as the Breaker been 20A on a 4mm cable this should cut out way before the cable deteriorates. Assuming the breaker is faulty and doesn't trip the rcd should come into force as soon as the cable breaks so it should be covered?
Just need to notify on test sheet but want full on reasoning...
Cheers for the help

 

[Murdoch]

What makes(s) are the MCB?

 

[Wooglepoops]

What makes(s) are the MCB?

It's an old proteus board
The new mcb used was a new style wylex

 

[Murdoch]

What have you been asked to do?

 

[Wooglepoops]

What have you been asked to do?

I'm fitting the wiring for a heatpump, buy whilst I'm there, I'm doing additional sockets, spot lights general bits to quite a few circuits. I'll be recommending a cu upgrade regardless but if he's not willing to change it that's fine but I'd like to let him know why if it's not acceptable. The only issue I can see is that the busbar will be holding a considerable amount of current and that could spill into the 4mm??...

 

[Wooglepoops]

To be honest the pv install looks nice & tidy just this "issue" - don't do pv so not familiar with the stuff..

 

[Sharpend]

Has this been done to isolate PV onto non Rcd supply?

 

[Murdoch]

TBH I would certificate my work and comment on the sub standard PV install

 

[Wooglepoops]

Has this been done to isolate PV onto non Rcd supply?

No its on the rcd side, it literally just looks like they couldn't find a Breaker to fit the board.

 

[Wooglepoops]

TBH I would certificate my work and comment on the sub standard PV install

Well yes that's what I'm getting at but is the piece of 4mm going to carry extra load from the busbar causing issues/cable to get overloaded? Or would this piece of cable just carry what's required to said Breaker?

 

[Murdoch]

Well yes that's what I'm getting at but is the piece of 4mm going to carry extra load from the busbar causing issues/cable to get overloaded? Or would this piece of cable just carry what's required to said Breaker?

extremely unlikely is my opinion.

 

[Wooglepoops]

This was my thinking but I just couldn't really decide on how it would pan out if left over time? don't like leaving dodgy bits and like to give the facts to customers rather than giving them a loaf of bull as I'm unsure.

 

[Murdoch]

This was my thinking but I just couldn't really decide on how it would pan out if left over time? don't like leaving dodgy bits and like to give the facts to customers rather than giving them a loaf of bull as I'm unsure.

it’s not up to you to persuade clients to do such improvements, life is too short.

not issues on your certs and move on

 

[binky]

No its on the rcd side, it literally just looks like they couldn't find a Breaker to fit the board.

Then it is dangerous, a standard solar PV inverter is allowed 3 seconds to shut down on loss of grid, so your client could have an accident, trip the RCD, but get killed by the solar system which hasn't shut down. In reality most trip out quicker than 3 seconds, but you can't guarantee it. So I would recommend moving the solar onto it's own mini board.

 

[Badger]

Then it is dangerous, a standard solar PV inverter is allowed 3 seconds to shut down on loss of grid, so your client could have an accident, trip the RCD, but get killed by the solar system which hasn't shut down. In reality most trip out quicker than 3 seconds, but you can't guarantee it. So I would recommend moving the solar onto it's own mini board.

So does that mean any solar inverter system should have it's own rcbo I take it

 

[Murdoch]

So does that mean any solar inverter system should have it's own rcbo I take it

Why a rcbo ?

 

[roys]

So does that mean any solar inverter system should have it's own rcbo I take it

Any I have seen or had dealings with were / are from the small garage type consumers units with a RCD and a MCB which was Henley blocked after the meter.

 

[Badger]

Why a rcbo ?

I was just asking I wasnt sure

 

[binky]

So does that mean any solar inverter system should have it's own rcbo I take it

Yes, but unless cabling run requires RCD protection, then I would put it on a MCB.

 

[Badger]

Yes, but unless cabling run requires RCD protection, then I would put it on a MCB.

Excuse the ignorance as I'm still new to solar learning side of things but why would you put solar on mcb not rcd where permissible