Bonding of services

[phawk]

Can somebody help me here please?

Just finishing a domestic rewire, TN-C-S, RCD split board etc. The problem I have is that at the beginning of the works I ran 10mm bonding cable to the services, now all the building work etc is finished, I've gone to connect the water bonding near the incoming supply and the builders have replaced all (visible) copper pipes with plastic! How does this affect me in regards to bonding services? This is always a contentious issue with me anyway as I see builders replacing more and more copper with pvc making the bonding effectively useless, unless you pull the house apart running bonding cable everywhere.

Also, is there a minimum ohm reading I should be achieving for my bonding? It's a long run, 15m or so? Tried the regs book but can't find anything useful....aidiabatic equation maybe?

I am using this as my Napit assessment, and I'd like to have a definitive answer for him.

Thanks

paul

 

[Octopus]

If the incoming water is plastic then no bonding required. That said if you've run the cable and you can attach it to copper you may as well do it!

 

[tuckermot]

main bonding 0.05 ohm,s to achieve touch voltage of max 50 volt potential ,with a fault current of 1000 amps

 

[phawk]

The incomer is copper, then plastic straight after the stopcock.

 

[tuckermot]

hard one this ,cross bond near the boiler 10mm then bond as suggested at the stop cock then contiual bond across the plastic pipe work ( not cut ) and bond again on the copper pipe all metal work can become live under fault conditions (230vs) then test with low ohms across pipe work ,between socket screws to radiators ect you are looking for a max of 0.05 ohms this will show that all the metal work is bonded and will achieve a fault path of 50v and pop the breaker in the required time

 

[ferg]

I would think that the ideal solution is to put a short length of copper after the stopcock and bond to that.
I genuinely don't know the reason for not being allowed to bond before it is.
I'm sure someone will educate me fairly quickly

 

[Jimmy Boy]

Can somebody help me here please?

Just finishing a domestic rewire, TN-C-S, RCD split board etc. The problem I have is that at the beginning of the works I ran 10mm bonding cable to the services, now all the building work etc is finished, I've gone to connect the water bonding near the incoming supply and the builders have replaced all (visible) copper pipes with plastic! How does this affect me in regards to bonding services? This is always a contentious issue with me anyway as I see builders replacing more and more copper with pvc making the bonding effectively useless, unless you pull the house apart running bonding cable everywhere.

Also, is there a minimum ohm reading I should be achieving for my bonding? It's a long run, 15m or so? Tried the regs book but can't find anything useful....aidiabatic equation maybe?

I am using this as my Napit assessment, and I'd like to have a definitive answer for him.

Thanks

paul

Refer to the regs.....the 17 Th!

Am I going to recite them no ! RCDs, max Zs, 1667 ?, disconnection times ? bonding requirements ? Do you actually know how to carry out a test for an Extraneous conductive part ? Do you know what it is ?
J

 

[ferg]

I've just recently read somewhere about the conductivity of water being poor and that the object of bonding is to bond the pipework that is extraneous.
I'm doing something rare here and sticking my neck out waiting for a potential barrage

 

[Jimmy Boy]

Explain to me what is an Extraneous Conductive Part ? And why is is it dangerous ?
J

 

[ferg]

Me or the OP?

 

[Jimmy Boy]

Either I'm easy Tiger
J

 

[tuckermot]

not part of the circuit but can become live under fault conditions or when the plumbers been lol

 

[WayneL]

Can somebody help me here please?

Just finishing a domestic rewire, TN-C-S, RCD split board etc. The problem I have is that at the beginning of the works I ran 10mm bonding cable to the services, now all the building work etc is finished, I've gone to connect the water bonding near the incoming supply and the builders have replaced all (visible) copper pipes with plastic! How does this affect me in regards to bonding services? This is always a contentious issue with me anyway as I see builders replacing more and more copper with pvc making the bonding effectively useless, unless you pull the house apart running bonding cable everywhere.

Also, is there a minimum ohm reading I should be achieving for my bonding? It's a long run, 15m or so? Tried the regs book but can't find anything useful....aidiabatic equation maybe?

I am using this as my Napit assessment, and I'd like to have a definitive answer for him.

Thanks

paul

You've got a Napit assessment and yet you are asking a question like the one I have highlighted???...............and you think the adiabatic equation applies to bonding????

They're going to seriously go down in my estimation if they pass you!

hard one this ,cross bond near the boiler 10mm then bond as suggested at the stop cock then contiual bond across the plastic pipe work ( not cut ) and bond again on the copper pipe all metal work can become live under fault conditions (230vs) then test with low ohms across pipe work ,between socket screws to radiators ect you are looking for a max of 0.05 ohms this will show that all the metal work is bonded and will achieve a fault path of 50v and pop the breaker in the required time

Is this a wind up - you must be having a laugh.

Cross bond near the boiler and then cross bond across every plastic insert.

What regs have you been reading.


What I don't get is how 'Jimmy Boy' can ask 'Paul' if he knows what an 'extraneous conductive part' is, yet proceeds to tick that he likes this post by you.......when you obviously don't know what an 'extraneous conductive part' is.

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not part of the circuit but can become live under fault conditions or when the plumbers been lol

Wrong..........completely!!

 

[Jimmy Boy]

You've got a Napit assessment and yet you are asking a question like the one I have highlighted???...............and you think the adiabatic equation applies to bonding????

They're going to seriously go down in my estimation if they pass you!





Is this a wind up - you must be having a laugh.

Cross bond near the boiler and then cross bond across every plastic insert.

What regs have you been reading.


What I don't get is how 'Jimmy Boy' can ask 'Paul' if he knows what an 'extraneous conductive part' is, yet proceeds to tick that he likes this post by you.......when you obviously don't know what an 'extraneous conductive part' is.

- - - Updated - - -




Wrong..........completely!!

wayne on the I Pad ticked wrong box genuine mistake dude
J

 

[ferg]

In this case the metal incoming service could introduce a different potential to that of the MET. Potentially increasing the touch voltage under fault conditions.
Hence recommending a short length of copper after the stop cock as regs state bond after it.