What are her cables - Lead-sheathed, Rubber or PVC?
I know who wired the house - "cables as short n taut as the crow flies" :-)
Consumer unit change requires an EIC, typical info is... a - IR test & continuity test of any rings b - CPC present (Yes or No) c - Ze measured or assumed from type of supply / DNO enquiry d - Zs limit (80%) from tables for that circuit breaker type (B) & rating (20A) e - Zs measured / calculated for each circuit and within Zs limit (d) f - RCD actual measured trip times are absolutely vital
In replacing the CU, any spark should at least check... a - There is no borrowed live/neutral condition (eg, on hall 2-way lights). A giveaway that there is would be both Lights-UP & Lights- DOWN on the same RCD rather than split between 2 RCD as 17th reg 314.1 would require.
This check takes 5 min.
b - That Light-UP & Light-DOWN have CPC (earth) present in the cable. If not she should have at least been advised plus a quick check that all lights are Class-II, backboxes are plaster or earthed-metal (separate 4mm 6491X earth) or plastic (Class-II), wiring accessories are plastic or M3.5 plastic screws used (not easy to find).
This check takes 5 min.
c - That MEB (Main Equipotential Bonding) is in place to Gas & Water if necessary, plus 17th bathroom requirements met
- Verification that no class-1 lights are in use without a CPC on the lighting circuit. The Green/Yellow 6491X bonding cable. Addtional work is required if the supply is TT (ie, she has her own earth rod).
This check takes 15 min. Earth rod tests & validation can take about
2hrs.
d - There are no obviously unsafe circuits, ie, insulation falling off, blackened & broken kitchen socket, 2-pin cord plug into light fitting (still have one of those myself, predates RCDs too :-)
There are a few more checks, but you get the idea. Most electricians would check for a-b-c before changing the CU as part of a "PIR" or Periodic Inspection Report, or check for them on their own. It is pretty "no-brainer" stuff for any spark as they do it day- in-day-out.
CU type. a - All circuits require RCD protection unless cables are surface run,
mother everything would require RCD protection almost certainly.
b - CU should be a minimum of Split Load with at least 2x RCD. Lights UP should be on RCD #1, Lights DOWN on RCD #2. That is to say not all lights should be on one RCD - if they are I would suspect there is a borrowed neutral/live which has not been corrected and really needs to be re "all lights out and mother down the stairs".
Depends on what was there previously.
If your new circuit was a single socket (outdoor) or light (kitchen) he could run that off an existing final circuit if that circuit would then not be overloaded (by that I mean its functionality not reduced). He would have to run surface wiring from that fuseholder to an external RCD such as a 13A RCD protected fused spur or 20A RCD protected enclosure etc.
If the new circuit was for something like a cooker, the meter tails could have been Henley Block split to a new CU with 32A RCBO protection, then check MEB is correct. There may not have been space in the CU location for this.
CU Change is notifiable to Building Control under Part P.
- Some DIYers do ignore this part, preferring to fix something unsafe and spend the =A3200 notification fee saved on RCBO or smoke alarm or fixing an otherwise unsafe install - but if they break BS7671 or equivalent named standard it is on their head re any faults introduced or potentially not rectified.
- Electricians ignoring it are another matter, not so much re breaking the law but the work *might* not be up to scratch. Realise an industrial spark with C&G 2382 2392 can not legally do a CU change unless he is a member of a competent body such as NICEIC ESC BSI (Electra?) and so on, whereas a 5-day trained NICEIC Domestic Installer can do it and need not actually comply with BS7671 or equivalent named standard in doing so, just be "reasonably safe".
A CU change to 17th should be about =A3450-650 depending on the work (and extending CU tails can be a fair bit of work and added cost re enclosures, checking circuits and so on).
Bottom-line. Do you have a piece of paper with the proper RCD test results on it? Does the CU have at least 2x RCD? Is the persons name on the Part P Competent Installer list? Are the lights on 1 RCD or split between 2 RCD? Is there a green/yellow wire running to the gas & cold water pipes if they are copper (or lead) in the house?
I dont think you are right about that. I am currently revising to take my 2382, and when passed, will not be able to change a CU,or fit a new circuit, but will be able to do minor works such as moving/adding sockets to an existing circuit.
________________________________ A) NON Competent Scheme Members.
People:
- DIYer
- C&G 2382 (2392) etc - but not scheme member
Can do:
- Domestic works may be performed anywhere
Works Non-Notifiable under SI2006 to BC:
- can move or add sockets to an existing circuit anywhere not in a special location
- no fee to pay, just comform with BS7671 or equiv named standard
Works Notifiable under SI2006 to BC:
- can change a CU
- must pay =A3150-200 fee for someone else to perform inspection & testing
________________________________ B) Competent Scheme Members.
People:
- NICEIC Approved Contractor
- NICEIC Domestic Installer
Can do:
- Domestic works may be performed anywhere
Works Notifiable under SI2006 to BC:
- Can move or add sockets to an existing circuit anywhere not in a special location
- Can change a CU
- Fee typically =A32, send paper copy to client, paper copy to BCO
A NICEIC Domestic Installer goes on a 5-day course and as far as I know can do anything subject to ongoing inspections, they do not need C&G 2382 2392 etc. The Domestic Installer tag was how NICEIC argued away the problem of insufficient domestic electricians to make the previous SI2004 work - where DIY could not change anything.
Unless a DI can not change a CU which I doubt because it would make the scheme useless. A DIYer can do anything except installing a new final circuit, adding a socket in a kitchen and changing a CU simply require notification to BC and a fee?
a) Full-scope means they can do a rewire - - without notifying BC by the DIY-route (=A3200 fee). b) Defined-scope means they can wire up a boiler etc - without notifying BC by the DIY-route (=A3200 fee).
I suspect a typical BG boiler servicing bod is defined scope DI for example.
Put simply...
- Domestic - you need to be Competent Scheme member OR pay BC fee for notifiable works.
- Industrial - you need to be Competent with Insurance. Most companies want to see C&G 2382 (2392) etc and a whole lot more if it is say a petrol station.
The former was about a paper trail for dead bodies & undeclared earnings. Sadly domestic cowboys tend to be long gone and a receipt is as scarce as "cheque will do". (The Cash Economy from this weeks experience must be freakin huge :-))
Whilst splitting the circuits by floors might be a separate requirement of the regs, and a shared circuit is thus a bad thing, does this necessarily indicate a borrowed neutral? In particular, can't a borrowed neutral exist anyway, even if the stair lighting is supplied (live anyway) correctly? (i.e. absence of the obvious shared circuit doesn't indicate that there isn't a borrowed neutral).
Last house of mine where I encountered this did have separate circuits for ground and first, but the two stair lights had neutrals from two different circuits. The middle landing's came from the ground floor (actually the rear extension which included both kitchen & bathroom), the upper landing's was from the first floor circuit that supplied the bedrooms.
What's the approved method of checking for a borrowed neutral, and proving that there isn't one?
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