Part-P

[micky p]

So do I.....I think we are ok to swap like for like but I believe we are not allowed to alter or add anything to an existing electrical circuit.That`s my understanding.

Spot on with what your understanding however as a boiler is a fixed appliance it should be hard wire and not on a plug and flex.when the spark rewires it to the fuse control unit you should then have to go back and ensure it complies with the MI cos the spark wont give a hoot.

The addition of an FCU would need a minor works certificate so to carry out this task you would need to be part p registered with level C.

i was told by a tutor at a college when i went on a Combi course approx 2 years ago that they prefer you to put a boiler on a plug and flex so that it can be totally isolated from the supply and you can see that it has been disconnected. you can also plug your socket tester in to check the supply.

 

[Paul Barker]

Err hemm, socket testers? Whose idea was it to let plumbers loose on electrics?

 

[arfurrrr]

corgiman quote

CORGI told me we have to record at least the earth loop impedance every time we work on the sparky side of a heating system

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where does it say that in the regs ? and what do they mean sparky side of heating ?

Are you saying if you remove the cable from a fused spur and refit it you have to carry out an ELI test?

Or what if you change pump on a system , thats in a special location ??

As I understand it these come under minor works and don`t require an ELI test and there for you don`t have to be part p registered to carry out repairs after the spur/socket.

If they are saying its good practice this is where they (CORGI) confuss the gas engineer .

And as for the sparky changing a plug to a spur and the gas engineer having to go back out and re-commission the appliance i think thats a load of tosh .

Are you saying the electrian can`t wire a spur !!!!!!!!

arf

 

[Paul Barker]

I can't give you the answer because I can't devote the time to fine combing the documents for the answers.

What I will say is that a Martindale plug socket tester is a very poor method of checking the installation to which you are about to attach new equipment. I would test it fully with low ohms test (if it's on a ring check the ring) insulation resistance test polarity confirmation loop impedance rcd's and other functional checks. I would also have to ensure that EEBADS is in good order and put it right before I did anything on the supply.

It is now a very common site on my jobs to see me unraveling 10mm earth cable half way round the house. Long gone are the days we slapped a sticker on the meter.

 

[corgiman]

corgiman quote

CORGI told me we have to record at least the earth loop impedance every time we work on the sparky side of a heating system

--------------------------------------------------------------------------------

where does it say that in the regs ? and what do they mean sparky side of heating ?

Are you saying if you remove the cable from a fused spur and refit it you have to carry out an ELI test?

Or what if you change pump on a system , thats in a special location ??

As I understand it these come under minor works and don`t require an ELI test and there for you don`t have to be part p registered to carry out repairs after the spur/socket.

If they are saying its good practice this is where they (CORGI) confuss the gas engineer .

And as for the sparky changing a plug to a spur and the gas engineer having to go back out and re-commission the appliance i think thats a load of tosh .

Are you saying the electrian can`t wire a spur !!!!!!!!

arf

I have no idea if it is or not in the regs but when I rang CORGI to ask them they said the We should be carrying out a Earth doings test on the circuit.

Who am I to reason why?

 

[oilman]

I can't give you the answer because I can't devote the time to fine combing the documents for the answers.

What I will say is that a Martindale plug socket tester is a very poor method of checking the installation to which you are about to attach new equipment. I would test it fully with low ohms test (if it's on a ring check the ring) insulation resistance test polarity confirmation loop impedance rcd's and other functional checks. I would also have to ensure that EEBADS is in good order and put it right before I did anything on the supply.

So do you have to go round and switch off or disconnect all equipment which might be plugged into the sockets? Then turn off the power to the ring?

 

[Biggles..]

The method i'd use for checking the ring(these methods vary from spark to spark and book to book) would be to isolate the ring split the tais in the meter, cross conect live1 cpc 2 & live 2 cpc 1, then go round each socket using low reading ohm for continuity .(dead check but there are more)This will indicat the consition of the ring(including spurs) and the cpc. Id repeat with L&n and cpc&n.
insulation resistance checks
Rebuild CU
Ze would then be measured, calculated or formed from enquiry usually no more than 0.35PME 0.8 TT(first live check)
Measure Zs at the socket with highest r1+r2 and ensure is no more than 3/4 of the tabulated value in the reg.
Check my maths Zs=r1+r2+Ze(which is why you need a tester that will give you values).
Check polarityPSC,PFC,checkRCD
Use socket tester for conformation.
Then id start work and recheck all on completion.

If in any doubt about what to do you dont need 2391 but guidance notes 3 would give you all you need to know.

As for minor works, on the form it asks under characterusucs of supply for Ze and the work under taken Zs so a loop tester would be needed.

As for sparks not being able to wire spurs, i know a few that cant wire heating jobs, so if ever a spark wired one of my boilers id go back and check as its my name on the benchmark and my name on corgi's registration form.(just my opinion)

 

[Paul Barker]

You have it lcgs, it's as you say.

Ring test is workaday knowledge even for part p quialified people let alone beyond. The veryt idea of getting any true measure of the condition of a supply from a Martindale plug in tester is proposterous. Since we can't use it to properly test a circuit why do we need it? Rhetorical question, to whic the answer is polarity. However during our continuity teste we check polarity, so now it serves no useful purpose, hence my abhorrence.

 

[Biggles..]

During r1+r2 you are checking the polarity with respect to the correct wiring orintation of the circuit under test, however true polarity is determined during Ze and Zs measurments.Usually indicated on your test equipment by leds. The polarity on many service heads have been known to be wired the wrong way by the LEC which until making an install live cannot be determined by coninuity checks alone.
Lee

 

[oilman]

.................. The veryt idea of getting any true measure of the condition of a supply from a Martindale plug in tester is proposterous. .................

I trust you have taken this up with Martindale, and reported them to trading standards for providing a misleading and consequently dangerous piece of equipment.

 

[corgiman]

My god I have awoken a monster

RUUUUUUUUUUUUUUUUUUUUUUUUUNNNNNNNNNNNNNN

 

[Paul Barker]

During r1+r2 you are checking the polarity with respect to the correct wiring orintation of the circuit under test, however true polarity is determined during Ze and Zs measurments.Usually indicated on your test equipment by leds. The polarity on many service heads have been known to be wired the wrong way by the LEC which until making an install live cannot be determined by coninuity checks alone.
Lee

Yes I have heard of this especially on new estates. Can't happen on pme though can it, because if it did all of the three phase supplies off that sub station would be in a hell of a mess?

I always confirm that neutral is near enough ground potential you don't need the martindale tester to tell you that.

My objection to the animal is that it is used instead of the prescribed procedure avialable to evryone in the osg. No point anybody buying gn3 (unless as a study aid for 2391, or to satisfy and inspector) it's loo paper, no additional information to what is in 7671 and osg.

For a plumber osg and an mft is adequate.

 

[JohnD]

...Yes I have heard of this especially on new estates. Can't happen on pme though can it, because if it did all of the three phase supplies off that sub station would be in a hell of a mess?...

It has been known to happen on PME, and the plug-in tester was not able to detect it (hence the safety bulletin banning reliance on plug-in testers). The case I am thinking of was an overhead supply to a rural building, but I imagine there would have been a fair current flowing through the main bonds, once they were installed.

 

[Paul Barker]

I didn't know there was a bulletin banning them but the Faraday centre staff where I did my eal level 2 and 2381 said it wasn't to be used as any kind of test, was mightily frowned upon by people who know what they are doing.

 

[JohnD]

Sorry - this was a company-specific in-house bulletin. I was at the time working for a company in the Electricity trade based in Ipswich, employing lots of people who would have been equipped with "better" testgear.