New Consumer Unit

[crystal ball]

No Eric, you do not take a chance, you test appropriately first.
I am not against using a clamp meter they can be quite a useful aid, however a 1mA resolution does not imply 1mA accuracy I`m afraid, still cvarry out appropriate tests with appropriate test gear as per C & G 2391 etc.
Yes I favour RCBOs one per circuit as you suggest - some point out it will not insure your total leakage per installation is not exceeded but neither will no RCD present as per rewireable fuses/plain MCBs either . Like you I would prefer not to fit a dual RCD board and favour RCBOs as stated (and I come from a time when an up front RCD was the single option really).
the "Borrowed Neutral " on lighting is usually the "Old Chestnut" that makes frequent visits upon us but the installation really should be tested first.
Yes caravans usually have a one RCD scenario .- in fact a one and one (one at the supply end and one in the caravan really).

So an "Emergency CU Change" negates testing for safety does it? No - You can always put some temporary lighting and power in if need be then do the testing of the dead existing tomorrow before the CU change.

Normally I don't carry lengths of festoon lighting and numerous extension leads, which have their own SAFETY issues, by the time I had done all that the new CU would have been fitted and tested. Leaving vulnerable people without adequate power and light overnight is not my idea of "professionalism"

 

[EFLImpudence]

I have never understood the timing and costing of these EICRs prior to a CU change.

Therefore am I right in thinking that all CU changes are a two day job and cost a couple of hundred pounds more than they otherwise would even when no problems are found?


Also, what are the problems shown by an EICR which would prevent a CU change and in such cases is the customer usually happy with just an EICR and a couple of hundred pounds bill instead of the CU change which they wanted?

 

[SUNRAY]

What about an "emergency" CU change, I have had a few of those when there is no time to do an EICR beforehand (pointless anyway) and sort out testing/remedials later

So an "Emergency CU Change" negates testing for safety does it? No - You can always put some temporary lighting and power in if need be then do the testing of the dead existing tomorrow before the CU change.

Let's get this into perspective before it heads south.

I totally agree with Flameports list as the way to go.

However is that really required on a small CU such as a garage with one light and one socket?

So putting this into perspective a small flat with say: Ring, lights and cooker circuits is only one more and very unlikely to have serious issues unless very old or botched.

Having dealt with several emergency CU changes where failures have occurred resulting in no service, I'd say the priority is to get some sort of service restored and as long as the supply, including bonding, is adequate and safe the next step is getting a CU in place followed by adding whatever circuits are healthy.

One doesn't tell a patient in the middle of dialysis Or a venue with a large freezer they have to wait until the following day. OK yes extreme circumstances but I have both T-shirts.

This is one of those topics where the lines between black and white turn a little grey. Ultimately the test and inspection has to be done and it is nice to get that and the repairs out of the way early. It's very likely the repairs will be completed by the assistant at the same time as the CU change and save time.

 

[ebee]

An appropriate amount of Inspect and test must be carried out.
Whether that amounts to a full EICR or a large part thereoff or just a bit is up to you.
Safety must not be compromised.
The installation may have been unsafe and unsatisfactory for years, that is out of your control.
However, when you change CU and power up then the installation must be safe and satisfactory for continued service and you may well decide that further testing and inspecting is appropriate/advisable .
You have no guarantee that the customer will allow you to proceed/ pay the bill for further testing.
So you must leave it safe.
It is no good saying "Well I left it as safe/safer than I found it and I left the customer with power and lighting but I intended to make it safe but the customer would not let me/events conspired against me and hence someone has now been injured despite my best efforts".
When you face a man wearing a wig and you are gripping the rail you must be able to show that you left things in a proper way.
If that means that the customer expires along with his iron lung then so be it.

 

[SUNRAY]

An appropriate amount of Inspect and test must be carried out.
Whether that amounts to a full EICR or a large part thereoff or just a bit is up to you.
Safety must not be compromised.
The installation may have been unsafe and unsatisfactory for years, that is out of your control.
However, when you change CU and power up then the installation must be safe and satisfactory for continued service and you may well decide that further testing and inspecting is appropriate/advisable .
You have no guarantee that the customer will allow you to proceed/ pay the bill for further testing.
So you must leave it safe.
It is no good saying "Well I left it as safe/safer than I found it and I left the customer with power and lighting but I intended to make it safe but the customer would not let me/events conspired against me and hence someone has now been injured despite my best efforts".
When you face a man wearing a wig and you are gripping the rail you must be able to show that you left things in a proper way.
If that means that the customer expires along with his iron lung then so be it.

I don't believe I have written anything different to that.

 

[crystal ball]

An appropriate amount of Inspect and test must be carried out.
Whether that amounts to a full EICR or a large part thereoff or just a bit is up to you.
Safety must not be compromised.
The installation may have been unsafe and unsatisfactory for years, that is out of your control.
However, when you change CU and power up then the installation must be safe and satisfactory for continued service and you may well decide that further testing and inspecting is appropriate/advisable .
You have no guarantee that the customer will allow you to proceed/ pay the bill for further testing.
So you must leave it safe.
It is no good saying "Well I left it as safe/safer than I found it and I left the customer with power and lighting but I intended to make it safe but the customer would not let me/events conspired against me and hence someone has now been injured despite my best efforts".
When you face a man wearing a wig and you are gripping the rail you must be able to show that you left things in a proper way.
If that means that the customer expires along with his iron lung then so be it.

All very well in a perfect world, I got a call one November, power off to lights, elderly lady out in the sticks, her son described the fuse boxes,(pre war by the look) I picked up a CU and got it installed before the light failed, certainly safer than the previous set up, certainly safer than leaving the old dear with a torch and extension leads. Went back next day to test etc. You say safety must not be compromised but you would be ok leaving someone with inadequate light and power overnight, with trailing leads all over the shop.

 

[Murdochcat]

Rarely?
How many board changes have you done?

Hundreds

 

[securespark]

If that's the case, I'm highly surprised you have not come across more issues changing non RCD boards.

I would certainly not deviate from flameport's advice.

 

[crystal ball]

If that's the case, I'm highly surprised you have not come across more issues changing non RCD boards.

I would certainly not deviate from flameport's advice.

Not even in the situation I described

 

[securespark]

I have been in that situation myself. If the wiring bells out OK, no worries. Where it hasn't, I have run a couple of temporary lights and sockets from a temporary board.

In these cases, it was only overnight or until Monday morning when the installation could be fully appraised and a decision made on how to proceed.

 

[crystal ball]

I have been in that situation myself. If the wiring bells out OK, no worries. Where it hasn't, I have run a couple of temporary lights and sockets from a temporary board.

In these cases, it was only overnight or until Monday morning when the installation could be fully appraised and a decision made on how to proceed.

Ok so with failing light and no heating you would carry out an EICR before installing a CU

 

[securespark]

It seems like you're on the attack: chill out!

I think whatever I say, however I try and defend my approach to this, you are going to pick holes in it, so in the words of Dragons' Den, "I'm out".

 

[ebee]

Pick one of the following as a defence for manslaughter.

1/ I was unable to safely put an electrical supply back on so the customer died.

or

2/ I put the electrical supply back on as best I could but the customer got electrocuted, his dog was injured and his house was burnt to the ground

 

[EFLImpudence]

This is silly.

Would someone like to answer my questions?

 

[ebee]

OK
Well if you do not follow :-
1 - Test and inspect the entire installation
2 - Repair all of the problems found
3 - Test again to ensure the repairs didn't introduce more problems
Then how do you know you will not be facing the questions I asked by the bloke in a wig?