Eng the point is probably moot now, but do you really not understand my point?

It is not about covering my arse, it is about protecting lives. If someone gets hurt badly, and I did nothing, what kind of person would that make me?
 
I see where you are coming from but if your bosses dont care how unsafe it is they will care nothing to hang you out to dry if you touch it. You have done your job now try to get a better job as these people do not deserve you
 
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I would connect all tanks ect earthing to main earth bar which is then fed to the main earth at the board. This is what we would do installing gen sets with fuel tanks, don't know how much help that is to your situation.
Obviously grading the main CPC correctly.

We would have all tanks, pipes, gennys all earthed to the change over panel them fed back to the main earth @ the main incomer.
If changeover was on the gen set we would put a main earth bar to connect all the different earths before it goes back to the main earth at supply.
Keeping everything at the same earth potential.
 
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Eng the point is probably moot now, but do you really not understand my point?

It is not about covering my arse, it's about protecting lives. If someone gets hurt badly, and I did nothing, what kind of person would that make me?


Embarrass your employers by having a 'whip round' and hopefully with the proceeds install RCD protection then at least you've made it safer than it was.
 
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Originally Posted by Inteificio
Eng the point is probably moot now, but do you really not understand my point?

It is not about covering my arse, it's about protecting lives. If someone gets hurt badly, and I did nothing, what kind of person would that make me?

I think we all see what your trying to do,but their comes a point where you have to start thinking about your own family first. Putting yourself in a position where you become part of any investigation and possible partial blame awarded against you, will have an effect on them. Also, having any conviction of this sort against you, will/can be a killer trying to gain potential employment with any large institutional employer!!
 
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Originally Posted by Inteificio
Eng the point is probably moot now, but do you really not understand my point?

It is not about covering my arse, it's about protecting lives. If someone gets hurt badly, and I did nothing, what kind of person would that make me?

I think we all see what your trying to do,but their comes a point where you have to start thinking about your own family first. Putting yourself in a position where you become part of any investigation and possible partial blame awarded against you, will have an effect on them. Also, having any conviction of this sort against you, will/can be a killer trying to gain potential employment with any large institutional employer!!
Ouch!!! but a reality check and 100% agree with you E54....its a knife edge he walks upon.
 
They do not want me to fix it.

Why do it then? If they don't want it done, don't touch it. If someone gets hurt after you've touched it, the company would have no problem pointing the finger at you. Leave it alone and then they will be liable.

I am slowly repairing it when the boss isn't looking, but I am not paying out of my pocket for the parts.

You won't have to if you don't touch it!


My understanding is that each circuit requires a designated CPC, and you are allowed to share this CPC.
I am using the CPC of an attached circuit.

If each circuit requires its own CPC (as per BS 7671) then how can you also share a CPC? Is it me?

I'm sorry but I am at a loss as to why you are getting involved in this. If the people holding the purse strings say NO and you continue to do work on it (and cut corners in doing so) then you only have yourself to blame.
You must be mad!

Unless there is another side to the story?!?!?
 
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I read it that each circuit requires a designated CPC.
So each circuit must have a fixed path to earth.
I do not think that each designated earth path must be unique.
As in, if you have a factory earth tape, each circuit has a CPC to the earth tape, then the earth tape becomes the CPC for multiple circuits at once.

Unsurprisingly this CPC would need to be marked at every point that it is used by multiple circuits.

If this is not the case, why is there a reg that says shared CPCs need to be rated only for the largest circuit?

p.s, You would also share a CPC on a sub-main.
 
Don't let Markythesparky confuse you ... I don't know why he has put each circuit requires its 'OWN' cpc as this isn't the case If he's under that impression then maybe he can show the REG' where he gets this from, conduit, trunking, steel wire armouring in a sub main supply can all be part of an earth return for multiple circuits.... re-read my previous post ive explained clearly and also reasons why you cant borrow the cpc like you suggested from an adjacent final circuit.
 
Don't let Markythesparky confuse you ... I don't know why he has put each circuit requires its 'OWN' cpc as this isn't the case If he's under that impression then maybe he can show the REG' where he gets this from, conduit, trunking, steel wire armouring in a sub main supply can all be part of an earth return for multiple circuits.... re-read my previous post ive explained clearly and also reasons why you cant borrow the cpc like you suggested from an adjacent final circuit.

I certainly wouldn't use trunking as my earth return for a 500kva gen! They also don't allow armor (steel bit) to be used as a CPC anymore it has to be separate conductor (client based).

Run everything in the same size it has supplied to it to a big earth bar on the wall. Run the largest size +50% for earthing goodness from this bar to the main earth at the incoming DB - job done.
All your trunking and tray ect will be earthed from the main board or boards anyway.
 
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I certainly wouldn't use trunking as my earth return for a 500kva gen! They also don't allow armor (steel bit) to be used as a CPC anymore it has to be separate conductor (client based).
With all due respect im replying regarding the OP's situe' and other than yourself there has been no mention of a Generator had this been the case then my advice would differ but as far as what ive put ill stand by my advice as its within the BS 7671
 
With all due respect im replying regarding the OP's situe' and other than yourself there has been no mention of a Generator had this been the case then my advice would differ but as far as what ive put ill stand by my advice as its within the BS 7671

I would still go separate CPC, every job I would run a separate CPC doesn't matter if its a light or a MVA gen.
What happens if one of your return trunking bends falls off the full system is kapoot?
They do get 'shared' though, just not using the mechanical protection of the install.
 
Im not nor have I ever said anything against the preferred method of having separate cpc's for each circuit, I was merely commenting on OP's confusion with the regs regarding cpc's been used for multiple circuits and using conduit, trunking etc always has been and is still a perfectly acceptable way to provide an earth and just because you practice other methods through preference doesn't mean its in anyway poor practice to use conduit or trunking as earth, im confused at your comment about the trunking bending or falling off ...you can say that about anything ...what if the earth terminal comes loose, or the earth breaks ....approaching the debate with that kind of thinking won't help the OP it will only lead to more confusion ....as I said im referring to the BS 7671 and if you do have a look it does stress that trucking, conduits etc should be mechanically sound so I cant see anyone having a problem if they decided to use it for earthing... to note though you cant just use anything metal as an earth path it has to meet criteria set in the regs.
 
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I'm going to stick my neck out a bit here and side (partially) with the op here.

I see darkwoods argument about the danger of borrowing a cpc from another circuit but I am struggling to find an actual regulation that says you can't. Plus I had exactly this problem with a domestic (class 1 lights without a cpc on the cct) where I was doing a CU change. I asked elecsa's helpline and got a clear answer - "yes you can borrow the cpc from another circuit as long as you make a note of it on the cert, after all you are just making it safer".

As long as you are making things safer (and safe to an acceptable level) and have documented what you have done and why then why not if it is all the customer/boss with accept? If you are worried about someone disconnecting the other circuit then stick a nice big label on the DB.

Having said all that, I do worry about doing the work without it being authorised by the management. That does leave you a bit open if the **** starts flying, especially if some pedant can show you have actually made things worse in some way (eg further compromised the IP rating etc).
 
Sympathies with the OP but maybe the company is having to make cuts due to the money they have wasted having inspections carried out only to ignore the findings...
 
I read it that each circuit requires a designated CPC.
So each circuit must have a fixed path to earth.
I do not think that each designated earth path must be unique.
As in, if you have a factory earth tape, each circuit has a CPC to the earth tape, then the earth tape becomes the CPC for multiple circuits at once.

Unsurprisingly this CPC would need to be marked at every point that it is used by multiple circuits.

If this is not the case, why is there a reg that says shared CPCs need to be rated only for the largest circuit?

p.s, You would also share a CPC on a sub-main.


I'm not going to get further involved in this argument, i've clearly made my veiws on this matter in earlier posts on this thread.


What i will say here, is that earthing tapes, around a factory wall are not provided as a means of supplying circuit CPC's, they are there as a supplementary means of bonding equipment and isolated extraneous metalwork and the like.
 
Personally I'd phone HSE if I were the op as this sounds like a timebomb waiting to go off.

that way it MUST be fixed,I'm sure one of the directors can keep his 2 year old BMW M5 another year rather than changing it for new.
 

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Industrial earthing problems - again deadly
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