Can an electrician swap my MCBs for RCBOs?

[Echo the husky]

Indeed, but one (albeit small) 'downside of RCBOs is that they can hinder/frustrate fault-finding to some extent, since if one trips one is given no indication as to whether it has tripped because of over-current or residual current.

Some brands have an indicator flag that changes colour depending if overcurrent or earth leakage tripped it.

 

[pete01]

Change a consumer unit every 10 years? Mmmm dunno...

My parents had the same wylex rewirable comsumer unit for 40 odd years until recently no trouble.

 

[flameport]

regarding DIY Solar that'll be available soon?

A novelty item of little benefit in most situations.
Problems being stored up for the future.

 

[flameport]

My parents had the same wylex rewirable comsumer unit for 40 odd years until recently no trouble.

But if trouble had occurred, they might have preferred something more recent with additional safety features.

Like driving a 40+ year old car with no seatbelts, no airbags, no antilock brakes and a mixture of cross ply and radial tyres.
All perfectly fine and safe until it isn't.

 

[Murdochcat]

All solar PV requires that, and solar cannot be on an RCD shared with other circuits

Reg number?

 

[JohnW2]

Some brands have an indicator flag that changes colour depending if overcurrent or earth leakage tripped it.

As I've been saying for a long time, that would be good, but I have to say that I've never seen any of the devices usually used in domestic installations that has such an indicator - which brands did you have in mind?

 

[JohnW2]

bit of a tangent now but what are your thoughts regarding DIY Solar that'll be available soon? It's very unlikely the average punter will be expected to know about the intricacies of their consumer unit- they'll be plugging their kit in to the closest most convenient socket and that'll be it. .... How could this be addressed?

As you probably indend to imply, if they become widely available and widely purchased by the general public then I would think that those issues will be essentially 'un-addressable' - as you say people will simply buy them and plug them in (to whatever).

If that happens, I suppose it might constitute an interesting, albeit 'unplanned', experiment to determine the actual importance (if any) of the sort of issues to which you refer!

 

[Echo the husky]

As I've been saying for a long time, that would be good, but I have to say that I've never seen any of the devices usually used in domestic installations that has such an indicator - which brands did you have in mind?

Schneider iC60 certainly do, I don't do much domestic stuff now. I thought the Eaton domestic stuff also did but the indicator is only on the RCBOs with AFDD combined.

I don't really look for an indicator when I'm fault finding I just grab the test meter.

 

[JohnW2]

Schneider iC60 certainly do, I don't do much domestic stuff now. I thought the Eaton domestic stuff also did but the indicator is only on the RCBOs with AFDD combined.

OK. As I said, I personally have never seen one with an indicator, but my experience is almost entirely in relation to domestic installations.

I don't really look for an indicator when I'm fault finding I just grab the test meter.

I'm not sure what sort of test meter would always tell you what an indicator could

 

[flameport]

Reg number?

Bidirectional devices is 530.3.201 which was added in Amendment 3 of BS7671 18th edition.

For PV not connected to RCDs which supply multiple circuits, in BS7671 this is mainly covered under disconnection times 411.3.2.1 where if the PV inverter is connected to multiple circuits, when the RCD disconnects the inverter will continue to supply power until it detects the loss of grid connection, which for most inverters is longer than 0.4s, so none of the other circuits connected to the shared RCD will comply on disconnection time.
The other item in BS7671 is excessive leakage current from the inverter, which together with leakage from the other circuits is very likely to be over the 30% (9ma) maximum for the RCD, 531.3.2

As for it being specifically stated as not permitted, that is in the IET Code of Practice for Solar PV, as discussed here: https://engx.theiet.org/f/wiring-and-regulations/31539/solar-pv-into-load-side-of-rcd

 

[Murdochcat]

Bidirectional devices is 530.3.201 which was added in Amendment 3 of BS7671 18th edition.

For PV not connected to RCDs which supply multiple circuits, in BS7671 this is mainly covered under disconnection times 411.3.2.1 where if the PV inverter is connected to multiple circuits, when the RCD disconnects the inverter will continue to supply power until it detects the loss of grid connection, which for most inverters is longer than 0.4s, so none of the other circuits connected to the shared RCD will comply on disconnection time.
The other item in BS7671 is excessive leakage current from the inverter, which together with leakage from the other circuits is very likely to be over the 30% (9ma) maximum for the RCD, 531.3.2

As for it being specifically stated as not permitted, that is in the IET Code of Practice for Solar PV, as discussed here: https://engx.theiet.org/f/wiring-and-regulations/31539/solar-pv-into-load-side-of-rcd

So it’s not a reg then.

Very few people have the COP

Why don’t the muppets that update 6761 simply as the reg like it’s written for EVs

And of course the regs aren’t retrospective , so a C3 on a EICR then

 

[ebee]

And of course the regs aren’t retrospective , so a C3 on a EICR then

Not always by default - a C1,C2, C3 etc is not defined as when it was allowed but now it is not allowed (that might have some effect on an inspectors judgement as to what extent something is considered safe or unsafe though) but must be based upon how safe or unsafe something actually is.
Purely because something was allowed 5,10, 100 years ago does not effect how safe it is .
Therefore something could be a C1 or C2 or C3 etc according to the problem you see in front of you.
Ask 3 different inspectors to look at one defect and you might well get 4 different answers but each inspectors answer should really be the same regardless of how long ago something was allowed or not allowed.

 

[Murdochcat]

Not always by default - a C1,C2, C3 etc is not defined as when it was allowed but now it is not allowed (that might have some effect on an inspectors judgement as to what extent something is considered safe or unsafe though) but must be based upon how safe or unsafe something actually is.
Purely because something was allowed 5,10, 100 years ago does not effect how safe it is .
Therefore something could be a C1 or C2 or C3 etc according to the problem you see in front of you.
Ask 3 different inspectors to look at one defect and you might well get 4 different answers but each inspectors answer should really be the same regardless of how long ago something was allowed or not allowed.

The vast majority are C3’s then

Just imagine the utter chaos if each version of the regs meant people HAD to upgrade their installations

 

[robinbanks]

DIY Solar

Please use the phrase “plug-in solar”; DIY solar is a different, more encompassing concept

 

[flameport]

So it’s not a reg then.

If you want a single specific item in BS7671 that states 'do not connect solar to multiple circuits' then no, there isn't.
If that type of thinking was continued, BS7671 would be thousands of pages of specific entries attempting to cover every situation possible.
Fortunately standards are not written like that.

Very few people have the COP

Very few people in the general population install solar. Those that do install solar certainly should have it.

And of course the regs aren’t retrospective , so a C3 on a EICR then

There is no requirement to update older installations to the current version of BS7671.

However the original enquiry was about installing RCBOs instead of what was there, so the choice of updating has already been made. Whatever is installed as the replacement should comply with BS7671 and other relevant standards.