I'll go with the definition of 'circuit' in BS 7671.
No - the circuit is already installed - no requirement to make the circuit comply with the regs for circuits in the 17th.
Oh come on...
Mine too.
We'll just have to agree to disagree then.
17th complying
- Thread starter ezekiel
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Practical comment.
If you extend a f.c. in a bathroom the cable might predate 13th wiring regs re zones or even lack a CPC. The problem with the former was realised with a cable being drilled whilst stood in a cast-iron bath.
It is unfortunate that we have regs & part p which allegedly try to help safety, but in reality it might have been better to target just that. Instead as many perceive a means to increase PAYE revenue.
Someone commented that BS7671 defines a circuit as that which is protected by a CPD? Does it not define a circuit as "a length of cable" and rather a final circuit as "a complete circuit protected by a CPD"?
Anyone got a 17th reg which defines "circuit" explicitly?
If you extend a f.c. in a bathroom the cable might predate 13th wiring regs re zones or even lack a CPC. The problem with the former was realised with a cable being drilled whilst stood in a cast-iron bath.
It is unfortunate that we have regs & part p which allegedly try to help safety, but in reality it might have been better to target just that. Instead as many perceive a means to increase PAYE revenue.
Someone commented that BS7671 defines a circuit as that which is protected by a CPD? Does it not define a circuit as "a length of cable" and rather a final circuit as "a complete circuit protected by a CPD"?
Anyone got a 17th reg which defines "circuit" explicitly?
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The definitions define "circuit".
An assembly of electrical equipment supplied from the same origin and protected against overcurrent by the same protective device(s).
An assembly of electrical equipment supplied from the same origin and protected against overcurrent by the same protective device(s).
I would have agreed with this until a spanner was thrown in the works :-
Mark Coles of the IET giving a seminar at Elex Harrogate,
this article also appeared in Wiring Matters issue 7 Spring 09
"Mark Coles also had some intersting ideas ref 17th compliance.
Take the ring final addition of a point to an existing ring final.
His take was that if adding to a ring final then the whole of that ring final must comply )including RCD protection) so the example given by some of the scheme providers of just RCDing the new cable and point was wrong. The whole of the circuit must comply, not just the addition.
He also pointed out that the whole "line of sight" back to the supply , including the suppliers bit must also comply , including such things as the Earth clamp scenario being corrected prior to the addition.
He was asked about installing say a shower in the bathroom, his answer was that not only should a new shower circuit comply but you then become responsible for the whole of that location too therefore you must RCD the lighting in the bathroom and any other such circuits even if you had not intended touching them just to do the shower install. When pressed about just doing a 17th compliant shower cct and then supp bonding all bathroom ccts he said no. "
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I wish someone had asked him how he thought householders would react to being told that if they wanted a new socket, or a new light, then their walls would have to be ripped apart, ceilings taken down and/or floors lifted so that the electrician, who according to him has become responsible for the compliance of the entire circuit, can check that all concealed cables are in the correct places, the right depth below the tops of joists, don't contain any concealed JBs, don't have sections which are the wrong size cable...
You guys are going to have to start carrying the other sort of breaker too - the ones that you use on concrete so that you can dig up patios and driveways etc to check on the compliance of the buried cable to the shed when you're asked to put a light over its door.
I'm not a qualified doctor, but I don't hesitate much in saying that Mark Coles is barking mad.
You guys are going to have to start carrying the other sort of breaker too - the ones that you use on concrete so that you can dig up patios and driveways etc to check on the compliance of the buried cable to the shed when you're asked to put a light over its door.
I'm not a qualified doctor, but I don't hesitate much in saying that Mark Coles is barking mad.
Thanks securespark re definition.
Coles comments are interesting.
MEB & validation of origin Ze etc are a requirement of ESQW and long known by anyone competent to be job #1 before you do anything.
The problem is the regulations are not prescriptive.
That creates an opportunity for cowboys, an opportunity for extreme interpretation, and a black hole of subjective but reasonable interpretation.
JPEL made an absolute dogs dinner of the 17th, gov't likewise Part P.
Many believe the 17th was written as though DIYers would operate in ignorance of Part P - I think more correctly it was written as though *cowboys* would operate in ignorance of Part P, the real problem.
Cowboys (and that includes QA who just collect the money and employ people who can't even terminate the sheath inside a wiring accessory) are worst because the ignorant customer *believes* it was done correctly, whereas a DIYer has some incentive to future question & improve work (they are physically present to do so & subject to its risk for the most part).
Hopefully the next gov't & IEE regs improve matters, however that would require a removal of the Stakeholder Bus-Writes Govt-Stamps culture. With business long boasting how it writes gov't policy, it could get worse. When will we have to rip-out PVC as "deadly in a fire" (ignoring wool based carpets, vinyl wallpaper fire propogation) or use sheathed CPC like France. A lot of opportunity for fake-economy creation here, gov't desired, business rewarded, socialisation of the costs without cost-benefit analysis. Too many charities fronting business interests, globally.
Coles comments are interesting.
MEB & validation of origin Ze etc are a requirement of ESQW and long known by anyone competent to be job #1 before you do anything.
The problem is the regulations are not prescriptive.
That creates an opportunity for cowboys, an opportunity for extreme interpretation, and a black hole of subjective but reasonable interpretation.
JPEL made an absolute dogs dinner of the 17th, gov't likewise Part P.
Many believe the 17th was written as though DIYers would operate in ignorance of Part P - I think more correctly it was written as though *cowboys* would operate in ignorance of Part P, the real problem.
Cowboys (and that includes QA who just collect the money and employ people who can't even terminate the sheath inside a wiring accessory) are worst because the ignorant customer *believes* it was done correctly, whereas a DIYer has some incentive to future question & improve work (they are physically present to do so & subject to its risk for the most part).
Hopefully the next gov't & IEE regs improve matters, however that would require a removal of the Stakeholder Bus-Writes Govt-Stamps culture. With business long boasting how it writes gov't policy, it could get worse. When will we have to rip-out PVC as "deadly in a fire" (ignoring wool based carpets, vinyl wallpaper fire propogation) or use sheathed CPC like France. A lot of opportunity for fake-economy creation here, gov't desired, business rewarded, socialisation of the costs without cost-benefit analysis. Too many charities fronting business interests, globally.
Some useful answers here
http://www.esc.org.uk/forum/forum_ed_thread.html
...and as usual at IET as many people disagree & agree with each point
...main switch one currently upsetting many.
http://www.esc.org.uk/forum/forum_ed_thread.html
...and as usual at IET as many people disagree & agree with each point
...main switch one currently upsetting many.
Up until attending his seminar and subsequently reading his article in Wiring Matters, I had no qualms about either :- 1/ adding and making the addition only comply fully or 2/ If practical making the whole circuit comply or 3/ Alternatively creating a new circuit just for the addition.
He argues 1/ is not allowed as the regs are presently written.
Similarly if adding say a shower to a bathroom I would have included a RCD on this circuit only and if no RCD on the other existing bathroom ccts I would ensure supp bonding was in place.
Actually I still supp bond in bathrooms because of the possible 7% failure rate on RCDs does not make me happy - but that is another story for another day.
His arguement was that it what the Regs say when you are certifying to the 17th and not given the option of certifying to a hybrid of the 17th & 16th (or earlier). He never said he agreed it should be written so but just that this was the way it was written.
He argues 1/ is not allowed as the regs are presently written.
Similarly if adding say a shower to a bathroom I would have included a RCD on this circuit only and if no RCD on the other existing bathroom ccts I would ensure supp bonding was in place.
Actually I still supp bond in bathrooms because of the possible 7% failure rate on RCDs does not make me happy - but that is another story for another day.
His arguement was that it what the Regs say when you are certifying to the 17th and not given the option of certifying to a hybrid of the 17th & 16th (or earlier). He never said he agreed it should be written so but just that this was the way it was written.
It seems as though the way I thought RCD protection was required (i.e. to cover an addition) is the same way the ESC answer EDQ2.
http://www.esc.org.uk/forum/forum_ed_thread.html which Mark Coles says is wrong
Will have a read up on the wiring matters article cheers ebee
At work we have showers, we also have our own substations and our own generating plant. How far up the tree do we have to go to find the origin of a circuit? Some of our final circuits probably go through at least 4 or 5 different distribution boards from a sub station before reaching their destination i.e. the final circuit for the lights in the shower. Where will the RCD go?
Similar if there is a sub main in a domestic supply?
http://www.esc.org.uk/forum/forum_ed_thread.html which Mark Coles says is wrong
Will have a read up on the wiring matters article cheers ebee
At work we have showers, we also have our own substations and our own generating plant. How far up the tree do we have to go to find the origin of a circuit? Some of our final circuits probably go through at least 4 or 5 different distribution boards from a sub station before reaching their destination i.e. the final circuit for the lights in the shower. Where will the RCD go?
Similar if there is a sub main in a domestic supply?
His argument says that if you change a light switch in a bedroom and that lighting circuit also goes to the bathroom you have to put the circuit on an RCD.
His argument says that if you put a surface mounted spur supplying a light on a socket circuit you have to RCD the entire circuit.
His argument says that if you put a light over the shed door you have to dig up the patio to check how the cable is buried.
Because his argument is that if you do anything to an existing circuit you have to ensure that the entire circuit complies with all of the 17th.
So here we are, ladies and gentlemen, in the home of the archetypal little old lady pensioner.
The pull switch for her bathroom light has broken. She has a Wylex rewirable with no RCD in sight.
As well as the light in the bathroom, there's an immersion heater, with a heated towel rail spurred from it (naughty, I know, but it's only 200W).
There's also a radiant heater on a spur from a socket circuit.
How much are you going to charge her to replace her broken pull switch?
Replacing a light switch is a maintenance task, no certification etc is necessary.
You may still advise them on any shortcomings of their installation but you are not forced to carry out any modifications to them.
You may still advise them on any shortcomings of their installation but you are not forced to carry out any modifications to them.
Somehow I don't think that a guy who tells you that if you alter one circuit in a bathroom you MUST update all the other ones that you hadn't even looked at, let alone touched, is going to agree with you.
I don't agree with the concept of having to upgrade all the other circuits in the bathroom which you haven't touched, I personally think that is way OTT.
Supplementary bonding wise they will have to be taken into account.
I'll have to read up on this guy!
Supplementary bonding wise they will have to be taken into account.
I'll have to read up on this guy!
For those of you who do not have a copy you should find it here
(Hope it works)
Download Wiring Matters issue 30.
Pasge 6 Alterations and Additions
Particularly the conclusion on page 11
http://www.theiet.org/publishing/wiring-regulations/mag/index.cfm
(Hope it works)
Download Wiring Matters issue 30.
Pasge 6 Alterations and Additions
Particularly the conclusion on page 11
http://www.theiet.org/publishing/wiring-regulations/mag/index.cfm
It's been mentioned here before.
His conclusion is that if you use surface wiring to add a surface mounted FCU to a socket circuit you have to put the whole circuit on an RCD because you are not simply taking responsibility for the newly installed or reconfigured element of the installation but all parts of the circuit.
His conclusion is that if you add a new luminaire, not in a bathroom but on a circuit which also supplies the bathroom, you have to put the whole circuit, or at least the bathroom segment, on an RCD because you are not simply taking responsibility for the newly installed or reconfigured element of the installation but all parts of the circuit.
And as I mentioned before, IMO he's barking mad.
His conclusion is that if you use surface wiring to add a surface mounted FCU to a socket circuit you have to put the whole circuit on an RCD because you are not simply taking responsibility for the newly installed or reconfigured element of the installation but all parts of the circuit.
His conclusion is that if you add a new luminaire, not in a bathroom but on a circuit which also supplies the bathroom, you have to put the whole circuit, or at least the bathroom segment, on an RCD because you are not simply taking responsibility for the newly installed or reconfigured element of the installation but all parts of the circuit.
And as I mentioned before, IMO he's barking mad.
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