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NozSpark

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I have a little quandary regarding a Inspection and test that I carried out over the last few days at a house that's been converted to flats

Now there's a CU that has a 30mA RCD main switch supplying the sub mains to the flats,,,,,, what code would you say???

IMHO... lets say that someone in the top floor flat receives an electric shock for some reason which trips the RCD.... now both the other flats lose power and the downstairs flat goes to the CU to investigate and sees that the RCD has tripped so he resets it...... unfortunately the occupant of the upstairs flat is still touching the cable/appliance that gave them a shock and gets another one :eek: .... so for me it's a C2 unless someone can convince me otherwise...

I realise that this would only get a C3 at most in a domestic,,, but that's usually under the control of a single occupant who you'd hope would investigate the cause

 
I can understand your thinking but unfortunately it is not a C2, but a C3.

A 30mA RCD would not cause sufficient harm to a "healthy person" and the repeated shocks would not cause alarm.

Having said all of that, the inspector ie YOU are the one calling the shots. If you believe that a danger exists then you have to code how you see fit.

For myself it would be a C3. I would also advise that it is changed at the earliest opportunity to avoid the scenario that you suggest.

 
I can understand your thinking but unfortunately it is not a C2, but a C3.

A 30mA RCD would not cause sufficient harm to a "healthy person" and the repeated shocks would not cause alarm.

Having said all of that, the inspector ie YOU are the one calling the shots. If you believe that a danger exists then you have to code how you see fit.

For myself it would be a C3. I would also advise that it is changed at the earliest opportunity to avoid the scenario that you suggest.




A C3 can mean a satisfactory report so for me it's a clear C2

A C3 with a comment can be ignored!

 
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Ok, so what if the flats have an rcd in their own CU's?? That solves that one... The Submain might require an RCD of its own due to cable routes [50mm etc] or type of earthing. So that would give two RCD's in series so what, although it might cause inconvenience, it would be safer!!

john..

 
The sub mains are buried T&E so they need 30mA protection..  and none of the flat CU's have local RCD protection

However adding local protection might not make any difference as only the remote one will trip,,,, unless they are active RCD's...that's a thought

However there are 10 CU's in the flats so that could become more expensive than individual RCD protection from the supply

The flats were previously split into bedsits..

 
At best you have inconvenience,

That's a C3 at most, imho,

You don't go round coding non RCD lighting circuits as C2 if they were installed to 16th,

Active or passive RCDs will make no difference as to which trips faster, the flat RCD might never trip,

What edition was the conversion carried out to could make a massive difference here 

 
At best you have inconvenience,

That's a C3 at most, imho,

You don't go round coding non RCD lighting circuits as C2 if they were installed to 16th,

Active or passive RCDs will make no difference as to which trips faster, the flat RCD might never trip,

What edition was the conversion carried out to could make a massive difference here 


It doesn't matter what edition it was installed to, the EICR is still a report on the condition when compared to the standards of the current edition of the regulations. 

A lighting circuit which has no RCD but requires one for buried cables will ordinarily be a C3 regardless of the date of the installation.

this is one of the reasons an EICR is unsuitable for assessing new installation work (despite what some labc departments appear to believe)

 
It doesn't matter what edition it was installed to, the EICR is still a report on the condition when compared to the standards of the current edition of the regulations. 

A lighting circuit which has no RCD but requires one for buried cables will ordinarily be a C3 regardless of the date of the installation.

this is one of the reasons an EICR is unsuitable for assessing new installation work (despite what some labc departments appear to believe)
It does matter what edition it was installed to,

A lighting circuit with NO RCD installed last year would warrant a C2, (possibly even a C1 depending on other factors)

Installed in 1993 it would warrant a C3

Why oh why did the great and good decide to eliminate the C4,,,?!?!?!

 
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It does matter what edition it was installed to,

A lighting circuit with NO RCD installed last year would warrant a C2, (possibly even a C1 depending on other factors)

Installed in 1993 it would warrant a C3

Why oh why did the great and good decide to eliminate the C4,,,?!?!?!


A lighting circuit with no RCD installed last year would not warrent a C2 at all. 

And to answer the op. C3 for me. 

 
I have an EIC for 2008 for "entire installation" but I think it was only a CU change at the supply and maybe some additions as the majority of the installation is red/black... 

When I get my head around it I'll start another post with some of the other gems that I've found... there are some good (bad) ones... and most of these are a definite C2

 
A lighting circuit with no RCD installed last year would not warrent a C2 at all. 

And to answer the op. C3 for me. 
Why not,?

If the cables(T&E) were buried <50mm deep then it didn't comply at the time of installation,

by default, imo, that has to be unsatisfactory. 

 
Why not,?

If the cables(T&E) were buried <50mm deep then it didn't comply at the time of installation,

by default, imo, that has to be unsatisfactory. 


Would you C2 a cpc with no green/yellow sleeving?

 
That's entirely different, it's not likely to constitute a danger, 

I would C2 a coloured cable being used as a CPC with no clear marking as to its purpose, just the same as I would C2 a G/Y being used for a purpose other than an earth, whether marked otherwise or not.

 
G/Y is not to be used as anything other than an earth, and if its in T&E then it could be a danger since its only sheathed and not insulated, so i would agree with C2,  but any other conductor used as an earth but not marked as such would be C3 at worst. same as a blue used as a live but not marked would only be C3

 
I've used the earth in a 3 core flex for the SW-L of a double insulated occupancy detector but adequately identified. Is that so bad? 

 
It does matter what edition it was installed to,

A lighting circuit with NO RCD installed last year would warrant a C2, (possibly even a C1 depending on other factors)

Installed in 1993 it would warrant a C3

Why oh why did the great and good decide to eliminate the C4,,,?!?!?!


The presence of danger or potential danger doesn't change purely based on the age of the installation. 

If something is potentially dangerous then it will be the same regardless of when it was installed.

the point of the EICR is to identify any defects or possible improvements relating to safety, bs7671 being the standard which defines what is, or is not, safe.

a lighting circuit wouldn't warrant any code on its own, but if it was installed in T&E buried less than 50mm deep it would be a C3, if it's in a bathroom without supplementary bonding it's a C2 and if supplementary bonding is in place it's a C3. 

Why not,?

If the cables(T&E) were buried <50mm deep then it didn't comply at the time of installation,

by default, imo, that has to be unsatisfactory. 


An EICR is not assessing compliance at the time of installation, it is assessing safety at the time of the inspection and test.

 
That's entirely different, it's not likely to constitute a danger, 

I would C2 a coloured cable being used as a CPC with no clear marking as to its purpose, just the same as I would C2 a G/Y being used for a purpose other than an earth, whether marked otherwise or not.


What is the potential danger from an unmarked cpc (assuming sound connections and acceptable Zs) ?

potentially dangerous describes a situation where something would become dangerous under fault conditions, which this would not.

yes. 7671 clearly states that a G/Y must not be used for anything other than a CPC

you should have used 4 core flex


What about the regulation which allows a g/y core to be over sleeved or otherwise marked up for another purpose? Or do you just ignore the regulations which don't agree with your opinion?

 
iirc, G/Y cannot be over sleeved and used as something else, unlike other conductors. i guess it could be over sleeved cream, but thats it

EDIT: 514.4.2

 
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