Consumer Unit Change

[Nickj]

Hi All,

I am tomorrow going to be changing a consumer unit ahead of my Elecsa assessment next week.

Just wanted to check that I'm not missing anything with regards to amendment 3.

I'm going to be using a BG consumer unit supplied with RCBOs.

It has a cut out at back for cable entry and so I am going to pass all cables through that using a grommet strip around the metal edges. Do I need to seal the entry hole? I believe not however I have heard arguments that it needs to be sealed. Passing all cables through the rear entry may require de-rating cables due to grouping however the cables enter the current board (3036's) through the rear. Can i therefore assume ratings are fine?

I am going to attach the consumer unit to the wall using dewalt wall dogs which require no anchor in wall meaning I don't have to worry about plastic wall plugs falling out in the event of a fire.


If the cables are too short (I sincerely hope they won't be) I'll use an adaptable box above the board to mount a din rail to extend wiring. Does this adaptable box need to be non-combustible too? (associated switch gear covers this possibly?)

Thanks in advance

Nick

 

[SparkyChick]

The advice I received from my scheme (NAPIT) was "it is recommended that you carry out an EICR before a board change to ensure there are no issues that could bite you in the buttocks" (somewhat paraphrased, but you get the picture). Note, recommended, NOT required.

I asked them because I did some basic checks (IR, Zs) on the circuits including an RFC all of which were good during my quote visit, did the board change and found an RFC had an r1 of 11.8kOhms and consequently had the pleasure of figuring out where the problems were before I could finish up and issue the cert, thankfully the customer was understanding, but could have cost me.

So I would add RFC end to end continuity to the list of checks to do. It's worth the time in the long run.

 

[Midwest]

Think this is getting some what overhyped. Whilst it might be prudent to carry out some rudimentary checks before replacing a CU, you don't want to be in a position of installing a bran sparky new dual RCD or RCBO populated CU, but can't turn it on 'cos its got some neutral earth fault, but I'm not spending my free time carry out some freebie 'EICR'. If the property has faults, that's extra, as mentioned in my T&C's.

 

[SparkyChick]

In general @Midwest I agree with you and it would be very easy to go way over the top, but personally, I don't do anything too onerous (basic checks at the DB, IR of as much as I can, Zs at a selection of places, Ze and PFC if poss, RFC continuity and a quick visual of as much as I can - this list has grown over time because I've been stung by issues previously), besides while I have the power off, I'm having a chat with the customer about any issues they may have with the current installation, or anything they might like changing while the work is going on, finding out more about the installation (age, any paperwork etc.) and hopefully enjoying a cuppa if they offer one before the power goes off.

I'd much rather have a good idea upfront of what I'm getting into and I'm pretty certain it goes down much better with the customer if you can warn them there may be a problem that will cost to fix rather than being stung with that on the day of the work. It just means both parties are better prepared for the final outcome.

Anyhow, you don't need to do an EICR, it's a personal choice and this is how I choose to operate because I don't look on it as wasted time, I look on it as building a relationship with a potential client.

 

[TheCodboy]

In general @Midwest I agree with you and it would be very easy to go way over the top, but personally, I don't do anything too onerous (basic checks at the DB, IR of as much as I can, Zs at a selection of places, Ze and PFC if poss, RFC continuity and a quick visual of as much as I can - this list has grown over time because I've been stung by issues previously), besides while I have the power off, I'm having a chat with the customer about any issues they may have with the current installation, or anything they might like changing while the work is going on, finding out more about the installation (age, any paperwork etc.) and hopefully enjoying a cuppa if they offer one before the power goes off.

I'd much rather have a good idea upfront of what I'm getting into and I'm pretty certain it goes down much better with the customer if you can warn them there may be a problem that will cost to fix rather than being stung with that on the day of the work. It just means both parties are better prepared for the final outcome.

Anyhow, you don't need to do an EICR, it's a personal choice and this is how I choose to operate because I don't look on it as wasted time, I look on it as building a relationship with a potential client.

Thats another thing i need to start doing..... Getting the kettle on before i knock the power off.

 

[Midwest]

In general
I'd much rather have a good idea upfront of what I'm getting into and I'm pretty certain it goes down much better with the customer if you can warn them there may be a problem that will cost to fix rather than being stung with that on the day of the work. It just means both parties are better prepared for the final outcome.
QUOTE]

USER]

At quotation stage I wouldn't carry out any tests whatsoever. I would however inform my prospective customer, that if my quotation was agreeable, before replacing the CU, I would indeed carry some testing (akin to what you mentioned), as well as the required tests when replacing the CU. My T&C's in my quotation, state it doesn't include rectifying existing faults, and I make that fully clear. This may actually be what you are referring to.

I would deal with each prospective installation on it's own merits. I have declined a few CU changes, because the existing installation appeared it such a poor state, that some or all of it might need replacing. I don't do EICR's & I don't do occupied rewires, I'll recommend someone else.

I think the point is, for the OP, a documented certified EICR is not required before replacing a CU, but obviously an EIC would be issued, which may include results of preliminary testing.

 

[Midwest]

PS somehow messed up my reply with SparkChick's quotation. Didn't mean to underline everything I said. Its not that important

 

[TheCodboy]

With regards to Test results sheet, What about ref method? Obviously on an existing install there is no way to verify this, so do we leave it blank or go with worst case senario??

 

[Midwest]

In a domestic property, it would be in walls, covered with insulation etc?

 

[SparkyChick]

I would try and make an informed assessment. The last one I did, the only place that was insulated was the loft, the rest was floor voids and cables in the gap between blockwork and plasterboard so it was fairly straightforward to make an informed decision.

Failing that I'd go for worst case, verifying the OCPD are still fine for the de-rated current carying capacity and possibly make a note on the EIC that it's not been possible to verify installation methods so you've assumed worst case and verified the OCPD are still suitable.

 

[HandySparks]

Thats another thing i need to start doing..... Getting the kettle on before i knock the power off.

Oh yes. If I'm turning the power off for more than a few minutes, I always ask the customer if they need to boil the kettle first. It quite often prompts an enquiry as to whether I'd like a cup of tea.

 

[TheCodboy]

I would try and make an informed assessment. The last one I did, the only place that was insulated was the loft, the rest was floor voids and cables in the gap between blockwork and plasterboard so it was fairly straightforward to make an informed decision.

Failing that I'd go for worst case, verifying the OCPD are still fine for the de-rated current carying capacity and possibly make a note on the EIC that it's not been possible to verify installation methods so you've assumed worst case and verified the OCPD are still suitable.

Makes sense, assume the worst, covers your back!

 

[Dave OCD]

Oh yes. If I'm turning the power off for more than a few minutes, I always ask the customer if they need to boil the kettle first. It quite often prompts an enquiry as to whether I'd like a cup of tea.

Me too, although it occasionally doesn't work, then I'll get cheeky and say something like 'a nice cuppa would be much appreciated' .

 

[Des 56]

Me too, although it occasionally doesn't work, then I'll get cheeky and say something like 'a nice cuppa would be much appreciated' .

I said those words once where the clients gobby teen son was left to look after the house
His reply was " I got better things to do than make you Tea" or more precisely two words to that effect

 

[Dave OCD]

It must have been tempting to give the little tw@t a slap !