Best Practice Guide No 4 Issue 7

[Murdoch]

Anyone else looked at the latest BPG no 4?

https://www.electricalsafetyfirst.org.uk/media/tx5i50ao/best-practice-guide-4-issue-7.pdf
Some useful clarifications but a couple of items that I found tricky to understand

Thoughts anybody?

 

[ProDave]

The one that stands out for me is "wrong" make of parts used in a CU is ONLY a C2 if certain types of damage are present. If no signs of damage it would appear mixed accessories in a CU are acceptable.

And a plastic CU is at most a C3 even if under an escape stair. Plenty seem to think a plastic CU is reason for an unsatisfactory.

It also makes clear that to perform an EICR you just need to be skilled competent and familliar with the requirements, but does not demand you hold any particular qualifications issued within a certain time. Why do I mention this? Well for at least 2 yeas now the Scottish Government have insisted to perform an EICR for rental properties you must be a member of a competent persons scheme like NICIEC or SELECT. This guidance note makes it abundantly clear that you do NOT.

If it were not for the fact I am retiring, I might take the Scottish Government to task on this one. I gave up doing EICR's for rentals because of this even though I was still doing new builds and Building Control were still accepting EIC's from me, which put me in the silly position I could certify a new install, but could not do an EICR on it in due course if it were used for rental.

 

[binky]

The one that stands out for me is "wrong" make of parts used in a CU is ONLY a C2 if certain types of damage are present. If no signs of damage it would appear mixed accessories in a CU are acceptable.

I though that was an interesting too. So, as I read it, if it fits properly and doesn't display thermal damage it's fine to 'mix and match' - make sense as anything that directly fits is probably from the same manufacturer. The only exception to that I can think of is some Chinese gear that is a direct copy of MK that I have encountered over the years.

Quite like the 'myths' section.

 

[Murdoch]

The C2 that caught my eye is the one for coding sockets that could be used to supply outdoor equipment

So over 20 years since RCDs were necessary for sockets it’s a C3

I have to say I disagree with this 100%

On the plus side having the “wrong” type of RCD is a C3 and not how Napit have tried to dictate a C2

 

[ProDave]

So a 3036 board install as long as it does not have any outdoor sockets and all in good order would only be a C3, so satisfactory.

 

[Murdoch]

So a 3036 board install as long as it does not have any outdoor sockets and all in good order would only be a C3, so satisfactory.

Not if I was inspecting it and definitely not if it’s a TT system

 

[Fleeting]

So a 3036 board install as long as it does not have any outdoor sockets and all in good order would only be a C3, so satisfactory.

Why wouldn't it be satisfactory?

 

[Murdoch]

Why wouldn't it be satisfactory?

Are you real?

 

[Fleeting]

Are you real?

Yes, why are BS3036 semi-enclosed fuses not compliant. For lighting circuits on 5A fuses the maximum Zs is high which could easily compliant for a TT system where there is no absolute requirement in BS7671 for RCD protection.

 

[Murdoch]

Yes, why are BS3036 semi-enclosed fuses not compliant. For lighting circuits on 5A fuses the maximum Zs is high which could easily compliant for a TT system where there is no absolute requirement in BS7671 for RCD protection.

Are you still using the 15th edition?

 

[Fleeting]

Are you still using the 15th edition?

You find where in the 18th Ed. it states it is an absolute requirement for TT systems to have RCD protection, the keyword here being "absolute".

 

[Murdoch]

You find where in the 18th Ed. it states it is an absolute requirement for TT systems to have RCD protection, the keyword here being "absolute".

Use of the word “shall” is the key word

So you would do a new install, TNS or TNCS without any RCDs then?

 

[Richard-the-Ninth]

Gentlemen, "play nicely"

 

[ProDave]

Nobody is suggesting doing a new 3036 install. Just discussing that unless you find a specific fault, there is no reason according to this guide, to fail an install just because it has 3036 fuses and no rcd.

 

[kerching]

Unless I’m reading this wrong, and to be brutally honest I’m not really arsed anymore,


Is NC a sort of dumbed down resurrection of a C4?

Just wondering

 

[Fleeting]

Use of the word “shall” is the key word

So you would do a new install, TNS or TNCS without any RCDs then?

Doesn't say "shall" regarding fault protection.
Would I install TN-S or TN-C-S without RCD protection, without a doubt I will do my utmost to avoid it but the earthing system is not relevant it is the installation method.
I am not pulling you down but your continual criticism of BS7671 may be ******** if you actually made an effort to understand it, your retort to me in #10 highlights your lack of understanding because fault protection by way of an RCD is not an absolute requirement.
If you have an encompassing knowledge of BS7671 then these Guides are not required so if you feel the need to consult them then maybe you need to question whether EICRs are your key strength.

 

[SPECIAL LOCATION]

Unless I’m reading this wrong, and to be brutally honest I’m not really arsed anymore,

View attachment 16535
Is NC a sort of dumbed down resurrection of a C4?

Just wondering

Sir Kerching, I have to assume you are several of these, (or equivalent lubrications), ahead of me and I am truly humbled by my poor performance......!!

But.... I do not believe that "C4" did exist??

New observations are "C1", "C2", "C3", "FI"
Whereas the old identifications were just "1", "2", "3", "4"

Obviously I may be too intoximacated to be right ???
and open to correction?

 

[Fleeting]

1 to 4 were Categories when it was a Periodic Inspection Report, 1, 2, FI and 3 are Codes for the long winded EICR. The former were far more relevant in their meanings.

 

[binky]

You find where in the 18th Ed. it states it is an absolute requirement for TT systems to have RCD protection, the keyword here being "absolute".

if i remember correctly with a rod over X ohms you can't meet requirements for disconnection times without RCD.

Even old versions of regs required VOELD for TT systems - I'm not old enough to remember any versions of those regs

 

[Fleeting]

if i remember correctly with a rod over X ohms you can't meet requirements for disconnection times without RCD.

Even old versions of regs required VOELD for TT systems - I'm not old enough to remember any versions of those regs

There is no absolute requirement in BS7671 for fault protection to be provided by an RCD. Whilst I understand this is the most logical solution it is not quoted as such.