Part P question

[JohnW2]

but that the schemes require their members to comply totally with BS7671.

Is this because the scheme operators cannot themselves evaluate the merits of an installation designed using common sense, basic principles and manufacturers data about components and cables ? They pass the buck for safety onto British Standards people.

That seems like a rather unfair suggestion. The scheme operators clearly need to require their members to operate to some set of detailed written standards and it would make no sense for them to re-invent the wheel by creating their own standards. They are, of course, as free as everyone else to make their own interpretation of BS7671 when there is less than total detail/clarity

It is ironic that an installation designed to a higher standard of safety than BS7671 requires cannot easily be installed by a member of a scheme yet can be installed by a DIYer where the LABC can evaluate using common sense, basic principles and manufacturers data about components and cables.

I'm not sure that's fair, either. In general, BS7671 indicates only minimum standards and actually says that other approaches are acceptable if they exceed the requirements of BS7671. I think that it is the people who make judgements about compliance in less-than-straightforward situations that are potentially an issue in situations such as you describe.

Kind Regards, John.

 

[JohnW2]

the Draft for Public Comment of Amendment 1 contained the following...

Yes, I read that, but since none of the 'now contains' exceptions mentioned actually made it into the final version of Amendment 1, I wondered if you really meant what you had written. I was also confused by the fact that what you were quoting clearly was not, per se, a draft of Amd 1, since the wording is that of a commentary about proposed changes, not a draft document.

If, as seems to be the case, you are confirming that you did mean what you wrote, it seems a little odd that all three of those draft changes were rejected following public comment. I wonder why?

Kind Regards, John.

 

[ban-all-sheds]

I was also confused by the fact that what you were quoting clearly was not, per se, a draft of Amd 1, since the wording is that of a commentary about proposed changes, not a draft document.

I don't think the actual DPC document is available any more.

If, as seems to be the case, you are confirming that you did mean what you wrote, it seems a little odd that all three of those draft changes were rejected following public comment. I wonder why?

I wonder too.

Does anybody know if they published the results of the consultation?

 

[JohnW2]

I was also confused by the fact that what you were quoting clearly was not, per se, a draft of Amd 1, since the wording is that of a commentary about proposed changes, not a draft document.

I don't think the actual DPC document is available any more.

So what were you quoting from - a commentary on the draft for consultation?

Kind Regards, John.

 

[ban-all-sheds]

Yes

 

[EFLImpudence]

I must admit, thinking as a scheme member, I have not before considered that the "departures from BS7671" box on the EIC should contain anything but 'none' although its size obviously allows for more than this.

Could I enter something which was contrary (perhaps the wrong word) to BS7671 but perfectly designed and safe and would that be considered acceptable (by the scheme operator)?

In other words, as long as the departure is noted, I can install as I see fit as long as it is safe and complies with an alternative or better standard.

Is this another can of worms?

 

[ban-all-sheds]

It's not the scheme operator signing the certificate, it is you.

It is not whether the scheme operator considers it acceptable which matters, it's whether you, being the person responsible for the Design, Construction, Inspection & Testing of the electrical installation, having exercised reasonable skill and care when carrying out the Design, Construction, Inspection & Testing, consider that the work for which you have been responsible is to the best of your knowledge and belief in accordance with BS 7671 apart from the departures which matters.

BS 7671 does have requirements for departures, so as long as yours comply with those then overall you have complied with BS 7671.

 

[JohnW2]

Could I enter something which was contrary (perhaps the wrong word) to BS7671 but perfectly designed and safe and would that be considered acceptable (by the scheme operator)?

The answer to the first part of that question is obviously 'yes' (you could write anythging you wanted!) - but you'd obviously have to ask the scheme operator whether they would consider it acceptable.

In other words, as long as the departure is noted, I can install as I see fit as long as it is safe and complies with an alternative or better standard.

Given that even BS7671 itself says (IIRC) that anything to an equal or better standard is acceptable, then one would hope so - but again it comes down to whether the scheme operators are knowledgeable and sensible, on the one had, or mindlessly blindly 'word-of-BS7671-obsessed jobsworths' on the other hand!

Kind Regards, John.

 

[EFLImpudence]

I have just thought of a good example.

Can I omit the totally unnecessary 3A fuse on extractor fans as this directly disregards the regulation as the manufacturer has stated I should fit one.

As the circuit is obviously perfectly satisfactory without said fuse then would noting the omission in the departures satisfy the scheme operator.

The above assumes that the customer is happy to waive the valuable warranty (should the manufacturer ask) in favour of one box fewer on their wall.

Edit - written before I saw the replies.

 

[JohnW2]

Can I omit the totally unnecessary 3A fuse on extractor fans as this directly disregards the regulation as the manufacturer has stated I should fit one.
As the circuit is obviously perfectly satisfactory without said fuse then would noting the omission in the departures satisfy the scheme operator.

In such a situation, I think it probably depends upon what one regards (or knows) is the reason for the manufacturer's instruction. The fixed wiring of the circuit is, as you say, perfectly satisfactory without the fuse. However, what if the manufacturer is thinking beyond protection of cable of the installation and knows that there are conductors within the fan that could become a fire risk if, under fault conditions, a lot more than 3A flowed through them? I know that the manufacturer should cover that possibility with a fuse within the product, but I'm sure that many don't.

In other words, I don't think one can necessarily be sure that the circuit (including the fan) will be satisfactory, let alone 'safe', unless one has an understanding of the reason for the manufacturer's instruction. Hence, if one doesn't have that information, I think it would be difficult to be sure that the omission of the fuse was BS7671 compliant - or even 'safe' in a more general (e.g. Part P) sense.

Kind Regards, John.

 

[EFLImpudence]

Can I omit the totally unnecessary 3A fuse on extractor fans as this directly disregards the regulation as the manufacturer has stated I should fit one.
As the circuit is obviously perfectly satisfactory without said fuse then would noting the omission in the departures satisfy the scheme operator.

In such a situation, I think it probably depends upon what one regards (or knows) is the reason for the manufacturer's instruction. The fixed wiring of the circuit is, as you say, perfectly satisfactory without the fuse. However, what if the manufacturer is thinking beyond protection of cable of the installation and knows that there are conductors within the fan that could become a fire risk if, under fault conditions, a lot more than 3A flowed through them? I know that the manufacturer should cover that possibility with a fuse within the product, but I'm sure that many don't.

In other words, I don't think one can necessarily be sure that the circuit (including the fan) will be satisfactory, let alone 'safe', unless one has an understanding of the reason for the manufacturer's instruction. Hence, if one doesn't have that information, I think it would be difficult to be sure that the omission of the fuse was BS7671 compliant - or even 'safe' in a more general (e.g. Part P) sense.

Yes, I wouldn't think the wiring inside the fan is only rated for 4A or 5A.

It's more likely because it is a motor.

 

[bernardgreen]

With no 3 amp fuse for the fan a motor whose winding melts out to a short circuit will blow the 6 amp fuse / MCB for the lighting circuit. House in darkness. High risk of injury if there is someone in the shower when the extractor fan motor takes out the lighting fuse / MCB leaving the person in sudden darkness.

The 3 amp provides bit of discrimination by going open circuit before the MCB can trip and thus leaving lights on.

 

[EFLImpudence]

With no 3 amp fuse for the fan a motor whose winding melts out to a short circuit will blow the 6 amp fuse / MCB for the lighting circuit. House in darkness. High risk of injury if there is someone in the shower when the extractor fan motor takes out the lighting fuse / MCB leaving the person in sudden darkness.

The 3 amp provides bit of discrimination by going open circuit before the MCB can trip and thus leaving lights on.

Yes, plus if it just gets stuck with years of talc. and dust.

As said, I think it negligent of the manufacturer not to fit an integral fuse which, usually, could even be a 1A.