Plumbers. Bless them.

[JohnW2]

On a new install there is no excuse at all for sleeving an earth.
I suspoect the exclusion is to cover the 50 years of bad practice that have left probably millionsd of households with this issue. It is unrealistic to expect a sparky or a plumber to rewire the heating controls in old houses. Its just not going to happen.
Better to give in - and get the conductors sleeved so at least the next bloke will see what's happening. ....

I agree - that pragmatic approach is probably the best one can hope for (for existing installations). As I wrote previously:

If one is dealing with pre-existing, buried, 3-core cable, then I can see that some people might think that ripping out and replacing the cable was rather too much of a hassle. However, if it's a new instal, or surface mounted (or otherwise easily replaced) cable, I can't see any excuse for not using 4-core (or 'more-core').

However, one has to accept that, even if one interprets the regs as saying that the oversleeving of the ends of G/Y insulation is just about acceptable, as EFLI has pointed out, such an arrangement probably remains non-compliant with 412.2.3.2 of the regs, which requires all cables to have a CPC.

Kind Regards, John

 

[doitall]

Why would the Information Engineering Technology know

The Institution of Engineering and Technology publish BS 7671.

I know.

the big green book, BS 6771:2008 amd 1 2011 17th edition
£60 quid to you

 

[doitall]

Ok I fired of an email to theiet.org technical dept.

May take a week.

Johnw2.

The question came about for an existing room stat that was being changed, like most I would never dream of over sleeving a new installation, when all you need is a multicore 5-6 wires normally does it.

 

[JohnW2]

Ok I fired of an email to theiet.org technical dept. May take a week.

Did you make it clear to them that, in addition to using a G/Y-insulated core (oversleeved, just at ends) as a live conductor, you're also talking about a cable that would have no CPC?

Kind Regards, John

 

[doitall]

Most modern room stats don't have an earth or docking post for one. In addition it's quite common for heating controls to be volts free.

 

[JohnW2]

Johnw2. The question came about for an existing room stat that was being changed, like most I would never dream of over sleeving a new installation, when all you need is a multicore 5-6 wires normally does it.

I'm glad that we at least agree on that.

Kind Regards, John

 

[EFLImpudence]

Most modern room stats don't have an earth or docking post for one.

It matters not, back to 412.2.3.2

In addition it's quite common for heating controls to be volts free.

Oxymoron, some volt free contacts have 240V connected to them.

 

[doitall]

Ok I fired of an email to theiet.org technical dept. May take a week.

Did you make it clear to them that, in addition to using a G/Y-insulated core (oversleeved, just at ends) as a live conductor, you're also talking about a cable that would have no CPC?

Kind Regards, John

I sent the same letter to everyone, requesting information about over sleeving the insulated green and yellow when used for heating controls.

I've also sent another letter to Napit disagreeing with their reply, with an explaination of how I read the regs.

 

[JohnW2]

Most modern room stats don't have an earth or docking post for one. In addition it's quite common for heating controls to be volts free.

Yes, but that's not the point - the requirement for a CPC in all cables is (a) in case something which does require an earth connection is subsequently connected to the cable and (b) to afford additional protection to the cable (in case it is penetrated or melts). Just as with Class II light fittings etc., there often is nothing in the fitting designed for termination of a CPC, so in those cases one has to terminate it in a bit of connector block, or something like that.

Kind Regards, John

 

[doitall]

Most modern room stats don't have an earth or docking post for one.

It matters not, back to 412.2.3.2

In addition it's quite common for heating controls to be volts free.

Oxymoron, some volt free contacts have 240V connected to them.

And as many don't have any volts.

The regs are certainly not as clear cut as you like to believe.

We shall see wont we, one way or the other.

 

[JohnW2]

I sent the same letter to everyone, requesting information about over sleeving the insulated green and yellow when used for heating controls.

OK - but as EFLI and myself keep telling you, that's only half of the issue - the other thing about which you should be seeking opinions is having a cable without a CPC. If they do not regard that as acceptable (per 412.2.3.2 of regs), the the question about colours/sleeving of the insulation becomes irrelevant.

Kind Regards, John

 

[doitall]

So if we look at requirement 514.4.2
It says
A bi colour combination green and yellow shall be used exclusively for identification of a protective conductor and this combination shall not be used for any other purpose.

I think that is self explanatory and the mention of single core cables should not devalue this.

As has been pointed out.

but it's not saying what you think it does
It's saying that a cable identified by the Bi colour combination green and yellow will be a protective conductor and nothing else
It does not say that you can not over sleeve said conductor and use it for a live conductor


Read the regs very carefully, not blinkered[/i]

 

[doitall]

I sent the same letter to everyone, requesting information about over sleeving the insulated green and yellow when used for heating controls.

OK - but as EFLI and myself keep telling you, that's only half of the issue - the other thing about which you should be seeking opinions is having a cable without a CPC. If they do not regard that as acceptable (per 412.2.3.2 of regs), the the question about colours/sleeving of the insulation becomes irrelevant.

Kind Regards, John

No John, it's the only issue.

Can the green and yellow be over-sleeved or not ? NIC say yes for heating controls.

 

[EFLImpudence]

And as many don't have any volts.

Then how do they work ?

The regs are certainly not as clear cut as you like to believe.

I think this one (412.2.3.2) is.

We shall see wont we, one way or the other.

If you find someone apparently in authority who agrees with you how will that change anything?

Why will you believe them and not us?

Oh yes, because they agree with you.

 

[EFLImpudence]

Can the green and yellow be over-sleeved or not ? NIC say yes for heating controls.

Then what will you use for the cpc?