I have often wondered... who writes these regs'??? 

A committee of course (or possibly a committee of committees) - the members of the main committee - JPEL/64 - are listed on page 13 of the current regs (although I gather there are few sub-committees too).

  - Andy.

Thanks, Andy... makes sense! BTW, do you know if these 'committee' people have ever worked on a building site, ,(OR, as domestic electricians'), as sparks'? Thanks!

Tomgunn said:

Thanks, Andy... makes sense! BTW, do you know if these 'committee' people have ever worked on a building site, ,(OR, as domestic electricians'), as sparks'? Thanks!

Well, I can't speak for everybody, but watch this from about 2:31 (minutes), which is where the link should take you: https://www.youtube.com/live/70PCl6XYjt4?feature=share&t=151

Hello, very good video! Pleased to note that some have worked onsite! You do realize... my post was part 'tongue in cheek?' It just amazes me, without upsetting anyone... you understand, the confusion that many electricians' find... trying to work out what some of the regs' actually mean.

Hi Tomgunn, yes, understand it was tongue-in-cheek, but a fair question all the same.

Tomgunn said:

It just amazes me, without upsetting anyone... you understand, the confusion that many electricians' find... trying to work out what some of the regs' actually mean

Appreciate that. I guess it starts early on .. school and college, when we learn 'V=IR' ... when in BS 7671 speak (well, in electrical engineering in general) it should be taught as U=IR.

We are constrained by standards drafting rules these days, and in fact have been for some time - Regs have been a British Standard for over 30 years now! But I guess that's one of the reasons the IET and other organisations produce guidance to help.

gkenyon said:

Appreciate that. I guess it starts early on .. school and college, when we learn 'V=IR' ... when in BS 7671 speak (well, in electrical engineering in general) it should be taught as U=IR.

R or Z? 

(Edited for typo.)

It may be better in terms of teaching, or more accurately learning, as it is the usually recipient of the knowledge that has to do most of the thinking work,  if instead of agonizing over the choice of Roman letters (or Greek symbols in some cases) for a specific quantity as if rigidly defined and then learning formulae by rote, more effort went into the understanding of the concepts.

Far more use to know the orientation of magnetic flux about a current carrying conductor or  line of moving charges, and how its alternation only introduces currents in suitably aligned adjacent conductors, rather than memorising that " B equals mu zero Mu R times H, without a feel for the units or direction of either.

That particular one avoids worrying about 'eddy currents' in thin steel boxes with exit holes, when the problem is one of magnetic hysteresis.

Mike

The first question in my C&G 2360 exam required me to use a pencil to draw the magnetic flux about a current carrying conductor on a piece of paper without any clues or hints, that is not possible with on-screen multiple choice exams in which the correct answer is always one of several possibilities presented to you.

In my mind... "errr, Tom. Run a 4 core 16mm SWA from the 6" x 6" trunking / busbar / switchgear, etc... to a TP&N CCU." OK... job done but HOW can this be??? Experience, perhaps? Learnt from some college works, and great foremen.. in the past? 

OK, I'm not having a go but, there seems to so much confusion how to interpret the current, (NO 'pun' intended),  IEE regs... somewhat 'ambiguous,' to say the least, at times. A simpler, haha, (am I asking for trouble here), set of regs that everyone can understand? 

All the best! 

In my mind... "errr, Tom. Run a 4 core 16mm SWA from the 6" x 6" trunking / busbar / switchgear, etc... to a TP&N CCU." OK... job done but HOW can this be??? Experience, perhaps? Learnt from some college works, and great foremen.. in the past? 

OK, I'm not having a go but, there seems to so much confusion how to interpret the current, (NO 'pun' intended),  IEE regs... somewhat 'ambiguous,' to say the least, at times. A simpler, haha, (am I asking for trouble here), set of regs that everyone can understand? 

All the best! 

Well that is the command to a wire-man, installer or technician. Somewhere calm, someone, and it may be the same chap doing it, but now with his 'design authority' or 'senior engineer' hat on.

 Maybe he now puts on a hat with the steel dome and the 'Viking horns' perhaps, instead of the baseball cap ? (*)

 The rated load, the route length and what it passes through on the way has been digested and a decision made if that 16mm cable is the best thing for the application.
That decision needs quite a lot of understanding and experience of environments and things like how cables get damaged, and not that much maths. But it is easy to set exams that ask about maths, and hard to test depth of understanding.

Mike

(*)We have a chap at work who really does this when he is editing the library of approved parts and their design rules in the CAD that could affect everyone's designs...  we know not to interrupt him then.