Interesting Regulation of Yesteryear

[denso13]

not ust lights, but

I was being simplistic. For some reason the electrical regs need to be forensically examined at every turn. I don't see this anywhere else to be honest.

 

[morqthana]

For some reason the electrical regs need to be forensically examined at every turn. I don't see this anywhere else to be honest.

Try the IET forums.

 

[securespark]

My CU DB has several of them.

I call them MCBs.

You haven't answered my query yet.

 

[morqthana]

You haven't answered my query yet.

Apologies - I thought I had.

I'll look back at earlier posts now.

 

[morqthana]

I wish you'd explain what you think they did mean.

I suspect they meant that sockets, light fittings, etc should all have switches so that they could be isolated without having to isolate the entire circuit, or functionally controlled in a practicable way, and that they assumed that common sense would prevail. This was in the era when best practice advice to skilled artisans was morphing into definitive prescriptions and proscriptions aimed at those who were less than skilled artisans.

As per my first point...please do explain the difference.

You may not believe it a question of what you think the difference is, but you are advocating very strongly for it, so please unravel it for me.

Basically "every" relates to every member of a group as a whole, and emphasises the group as a whole, and "each" relates to them individually.

 

[securespark]

Yes I guessed that but when was it removed, I thought perhaps it was a throwback to then.

Just gone through the 14th Edition, 1966.

A58.

An appliance or lighting fitting connected to an installation other than by means of a plug and socket-outlet shall be controlled by a switch or switches which shall be arranged to disconnect all live supply conductors.
For an appliance fitted with heating elements which can be touched or into which more than one phase of the supply is introduced, the switch shall be a linked switch arranged to break all the circuit conductors.

NOTE:- For the purpose of Regulation A58, a circuit-breaker may be used as a switch; and a bell transformer is not regarded as an appliance.


Two points here from a personal point of view... This is the first appearance of circuit breakers I have seen in the regs. IIRC, the BS for 3871 hails from 1965.

Second, although not classed as an appliance, I have seen many bell transformers with an adjacent light switch for isolation. Indeed, that is how I was told to install them myself, when I started in 1983.

You'll have to wait for the next thrilling installment as to whether I can find anything in the 15th Edition, 1981...

Chances are, the answer will be no, because the index makes it so hard to find stuff in the 15th onwards, compared to previous Eds.

 

[ericmark]

disconnect all live supply conductors

When did live include neutral? I know neutral and line are classed as live now, but was that the case back them?

 

[ebee]

Indeed, some might say that "Any conductor/part that (normally) carries current as part of its intended function is considered "Live" such as switched L or perm L or such as N (by convention only a shared E & N such as a PEN (CNE) is not considered Live! "

I am not convinced that exception convention is the best of ideas really.

 

[securespark]

When did live include neutral? I know neutral and line are classed as live now, but was that the case back them?

Not sure if they're talking about the neutral being a live conductor or whether they were referring to "more than one phase" in A58.

 

[mikehammer69]

Not sure if they're talking about the neutral being a live conductor or whether they were referring to "more than one phase" in A58.

Don’t think neutral is included in live conductors

They refer to switching all lighting live conductors which presumably has never included a neutral ?

 

[securespark]

An appliance or lighting fitting.

So could include a neutral.

 

[mikehammer69]

An appliance or lighting fitting.

So could include a neutral.

Stop would ya

That means lights and appliances must have all live conducors disconnected

So lighting therefore would need the neutral switched if the definition of 'live' includes N at that time

 

[mikehammer69]

Anyway I just noticed and somebody else I think already said

The rule says a CB can be used as a switch so therefore it can only be line/phase

 

[securespark]

OK, if the appliance has heating elements that can be touched (like the old open element wall-mounted fires), or an appliance fed by more than one phase, the switch has to break all the circuit conductors, ie live(s) and neutral.

Anyway, I'm off to dig out my copy of the 15th, 1981 to see if that reg lives on!