main bonding

[ample current]

Is it ok to clamp 10mm earth cable to the gas pipe then to the water pipe and then to the Installation earthing terminal or do the have to be sepatete cables, the cable runs are about 3m.

Many thanks in advance
Mark

 

[malcolmsanford]

Yes you can daisy chain a bonding conductor as you say. It is preferable to leave it as 1 continuous cable, but that is not a regulation just a guide and good practice

 

[Edd]

I always thought it was a reg that it was ok to bond using one cable but couldnt be cut!
must be one of those misconseptions where people read and here something and assume its regs and then it just gets passed along as regs.. thanks learn somthing new everyday..
Saying that I would be unhappy to have a joint just incase it becomes disconected then you loose both bonds and some of them crappy earth clamps just ask for the cables to fall out....

 

[Graeme Harrold]

I was under the impression it could be done, think the word used is "contigious", not got the regs to hand....

 

[telectrix]

that's the exact reason you should only use an uncut cable if using 1 for both gas and water.

 

[Dan23584]

I agree, one continuous cable to both.

 

[Octopus]

This is a great example where BS 7671 should be written in an unambiguous manner. As others have said its good practice and in the guidance notes you don't have too!!!

 

[Guest123]

GN8 only 'recommends' an unbroken conductor.

There isn't a hard & fast reg but it is best electrical practice IMO, just incase one service or the other is altered etc.

528.3.3 could be construed as applicable here, depending on your own interpretation of BS7671.

 

[WDMDL]

My tutor was of the opinion that one cable for both services was acceptable, so long as it wasn't joined at the BS951 or similar. He referred to 528.3.3.

Nothing wrong with through-crimping away from the BS951 though, so that the cable can be looped round the terminal in the spirit of 528.3.3

I chose to do it that way when a renovation on a particular house resulted in the water supply now entering on the opposite side of the house. saved a lot of hassle!

Simon.

 

[Geordie Spark]

I always thought it was a reg that it was ok to bond using one cable but couldnt be cut!
must be one of those misconseptions where people read and here something and assume its regs and then it just gets passed along as regs.. thanks learn somthing new everyday..
Saying that I would be unhappy to have a joint just incase it becomes disconected then you loose both bonds and some of them crappy earth clamps just ask for the cables to fall out....

Unless you crimp or solder lugs onto the cables.

 

[gdr7671]

yes you can but do not​ cut the cable at the first connection

 

[malcolmsanford]

yes you can but do not​ cut the cable at the first connection

Why not?

I think we are stretching the interpretation angle a little if quoting reg 528.3.3 in regards to a bonding conductor having to be continous. In fact if you wanted you could work it the other way and have the reg interpret a reason not to have it so.

The reg relates to electrical services, the bonding, when it is within proximity to one or more non electrical service, the gas and water pipes, and so shall be arranged that any forseeable operation carried out on the other service will not cause Damage to the electrical service or the converse.

It then gives us the options of suitable spacing between the services or use of mechanical or thermal shielding, which having a continous cable, gives neither.

In fact you could say that having the continous cable could cause damage if a plumber was working on a pipe and there was not enough slack for them to be able to work on say braizing, because the cable was continous and he/she could not keep the bonding out the way of the flame.

OK they could disconnect all terminations and take the bond away completely, but would they bother to reconnect, would they go through the chew of trying to fit a 10mm "eye" onto a BS 951 !!. Perhaps yes and perhaps no, but to my mind if the plumber was in two minds to bother to reconnect the bonds, he may feel more inclined to do so if they were lugged.

To be honest I see no problem with running a cable from the MET to a pipe, cutting it and lugging it, then lugging another section of cable and taking it daisy chain to another pipe and so on.

How many sparks have struggled, especially now with trying to "eye" a 10mm cable onto a BS 951 clamp, and to be honest have said that's good enough, when the connection wasn't mechanically as sound as it should be.

Bottom line is preferred method would be a bonding cable for each service then lugged onto a BS 951 clamp. If you have to daisy chain then yes a continous conductor is preferable, but if I saw one that had been cut and lugged as above I would not loose too much sleep over it.

 

[johnboy6083]

whilst on the subject of main bonding, whats your gents opinion on bonding to production pipework, that enters and leaves a building?
I work in pumping stations, and treatement works, and we have pipework that enters and leaves a building. Should it be bonded at entry and exit, as close as possible to the entry/exit? should it be bonded at one end, and assume that it is then at the same potential as the MET?
Can the SWA to the pumps (cable over 50mm2) be used as main bonding, as the pumps and bases are steel, and electrically continious?

Id be interested in your opinion.

John

 

[malcolmsanford]

John if they are extraneous conductive parts then yes they should be bonded, reg 4113.1.2 (iii).

Not sure why you want to bond them on exit mate, but certainly on entry.

As for the 50mm SWA well normal SWA will give you copper eqiv of about 32mm and XPLE dead on the 25mm required in reg 544.1.1

Had to edit that of course 50mm 2 core XPLE would only be about 22mm copper eqiv and therefore not suitable

 

[gdr7671]

I agree entirely with you. I have had refusals to connect supplies by DNO's for cutting and lugging bonding cables. Their argument being if disconnected by a plumber or gas engineer at the first connection for any reason, the bonding to the final (or following connections would be lost. They have argued reasons about the ESQC regulations 9 & 26 although i can find no mention of this in this document.

 

[malcolmsanford]

Well section 9 is concerning PME supplies and section 26 does indeed appertain to non connection of supplies.

There is a note in section 9(4) concerning and mentioning

Special consideration should be given to the earthing and protection arrangements for certain installations where reliance on the connection of the consumer’s protective conductor with the distributor’s combined neutral and protective conductor could result in more significant risks. For example, installations where it may prove difficult to attach and maintain all the necessary equipotential bonding connections (e.g. farms or building sites),installations at certain wet environments (e.g. swimming pools and petrol filling stations) and certain installations outside the equipotential zone of buildings (e.g. certain types of street furniture). Further advice may be sought from the Health and Safety Executive or the Institution of Electrical Engineers.

Taken from the ESQCR-2002

The above extract and highlighted section maybe what the engineer(??) was referring to, especially as if the engineer, and I use the broadest possible term here, does not have a clue what he is talking about.

 

[ample current]

Thank you for all your replys, i have connected it using one cable not cut, just stripped at the clamp where it passes the water pipe on its way to the cu.
Cheers
Mark

 

[gdr7671]

Well section 9 is concerning PME supplies and section 26 does indeed appertain to non connection of supplies.

There is a note in section 9(4) concerning and mentioning

Special consideration should be given to the earthing and protection arrangements for certain installations where reliance on the connection of the consumer’s protective conductor with the distributor’s combined neutral and protective conductor could result in more significant risks. For example, installations where it may prove difficult to attach and maintain all the necessary equipotential bonding connections (e.g. farms or building sites),installations at certain wet environments (e.g. swimming pools and petrol filling stations) and certain installations outside the equipotential zone of buildings (e.g. certain types of street furniture). Further advice may be sought from the Health and Safety Executive or the Institution of Electrical Engineers.

Taken from the ESQCR-2002

The above extract and highlighted section maybe what the engineer(??) was referring to, especially as if the engineer, and I use the broadest possible term here, does not have a clue what he is talking about.

I agree as i said before. But when you need the supply connecting it is anything for a quiet life. Why argue with a meter fixer even if i am a registered engineer

 

[i=p/u]

ok what about this one....

theres another sink being put into utlity room in house, does this need to be main protective bonded??

ive priced for the socket outlets and ligting in that room... but not bonding.. suppose test it

 

[lardy]

On the 2391 fault board (practical taken last week) one of the faults was the main bonding conductor not continuous. The task was to find “12 non compliances”, not bad practice.
If it was a non-compliance or not, it was what they were looking for!

 

[ringer]

ok what about this one....

theres another sink being put into utlity room in house, does this need to be main protective bonded??

ive priced for the socket outlets and ligting in that room... but not bonding.. suppose test it

Main bonding is to gas and water supplies, not to sinks. You may or may not need to supplementary bond a sink. You did of course check the main bonding existed and was up to scratch, didn't you?

 

[malcolmsanford]

ok what about this one....

theres another sink being put into utlity room in house, does this need to be main protective bonded??

ive priced for the socket outlets and ligting in that room... but not bonding.. suppose test it

Is there a metallic waste pipe?

Is the water supply taken from a different source than from the main water supply?

Is there any extraneous conductive parts on the sink?

Does the utility room also contain a bath or shower?

 

[Spazz]

I see that some have mentioned lugs and eyes on the earthing bond, when I was working as a mechanic (yes with 12v and 24v) you could get a strip of metal with 2 eyes - 1 each end.
You would bend this around the cable and solder it so the 2 eyes met and put a bolt through to connect the earth (neutral on a car) to say the body or the engine. Would this be accepted with 240v as the clip I feel is big enough to handle it plus its only an earth.
The clip is 10mm wide by 50mm long, so it will bend around upto 12mm cable. If I can find a link I will post it.

 

[Guest112]

my mate failed his am2 because he cut the cable seems a bit harsh considering its not a reg but only good practice like

 

[BillyTheSparks]

I'm not sure if I'm making this up, but i believe that you can get 'Y' shaped crimps.

If so would it be acceptable to take one 10mm to where the gas and water pipes are (if they're next to each other) and then crimp in the 'Y' crimp and take two seperarte 10mm leads to each BS951?

I have never done this, just curiosity. :49:

 

[Geordie Spark]

I'm not sure if I'm making this up, but i believe that you can get 'Y' shaped crimps.

If so would it be acceptable to take one 10mm to where the gas and water pipes are (if they're next to each other) and then crimp in the 'Y' crimp and take two seperarte 10mm leads to each BS951?

I have never done this, just curiosity. :49:

There's a thread about it here:

Can you crimp more than 2 cables? - DIYbanter

Post #6 briefly mentions "y" shaped crimps.

 

[BillyTheSparks]

There's a thread about it here:

Can you crimp more than 2 cables? - DIYbanter

Post #6 briefly mentions "y" shaped crimps.

I have seen that before, but the only methods the posts go into are Wagos and through crimps; with two wires shoved into one end and a doubled wired shoved in the other.
I'm sure I've seen them on a wab site for earthing, but cant remember the name and cant find it at the moment.

 

[Engineer54]

whilst on the subject of main bonding, whats your gents opinion on bonding to production pipework, that enters and leaves a building?
I work in pumping stations, and treatement works, and we have pipework that enters and leaves a building. Should it be bonded at entry and exit, as close as possible to the entry/exit? should it be bonded at one end, and assume that it is then at the same potential as the MET?
Can the SWA to the pumps (cable over 50mm2) be used as main bonding, as the pumps and bases are steel, and electrically continious?

Id be interested in your opinion.

John

The answer to this question is ''YES!!'' In every Hospital building as well as many other types of buildings, i've been involved with, where metallic pipework of any kind, enters and leaves the building. Where that pipework has a value that requires bonding under normal situations, you would bond at entry and exit points!! Example ..medical gas pipes, steam pipes, HVAC chilled water and return pipes, etc, etc!!

And as the conversation is covering linking services with single bonding cables, ...for instance Medical gases will generally all enter the building (and probably exit the building) as a group and would therefore be linked via a single bonding conductor, similarly this would also generally apply to Chilled water pipework etc, too. Can you imagine taking a separate conductor to each pipe, hell you'd need a 6''X 6'' trunking system just to hold all these bonding conductors, let alone a very extended MET or earthing bar...lol!!!

 

[BillyTheSparks]

Earth Crimp Connectors – Earth Bonding, Earth Crimp, Earth Clamp » Products

Anyone seen these before?

It doesn't look like you could get 2x 10mm in them but useful in their own way i guess

 

[i=p/u]

1..plastic waste pipe
2..il assume is copper piping from main water supply at first sink
3. the sink itself would be extraneous
4. no bath or shower

and doesnt require suplementry bonding if has main bonding.. which i havent looked yet. i put on my quote confirm price after site visit...

Is there a metallic waste pipe?

Is the water supply taken from a different source than from the main water supply?

Is there any extraneous conductive parts on the sink?

Does the utility room also contain a bath or shower?

 

[La Poste]

Is there a metallic waste pipe?

Is the water supply taken from a different source than from the main water supply?

Is there any extraneous conductive parts on the sink?

Does the utility room also contain a bath or shower?

Just a quick question, why are you asking if the utility room also contains a bath or a shower?

Thanks.

 

[jamie-spark]

John if they are extraneous conductive parts then yes they should be bonded, reg 4113.1.2 (iii).

Not sure why you want to bond them on exit mate, but certainly on entry.

As for the 50mm SWA well normal SWA will give you copper eqiv of about 32mm and XPLE dead on the 25mm required in reg 544.1.1

Had to edit that of course 50mm 2 core XPLE would only be about 22mm copper eqiv and therefore not suitable

It is my. Understanding when swa is used as a bonding conductor we work out its copper equivelent which for a 50mm 2core xple works out at about 8.5mm when its used as an earthing conductor it is 22mm .

 

[R4BOE]

i think your correct on this point jamie-spark

 

[i=p/u]

theres a data sheet on the forum for this, or you can use the (bgb) book to work this out..

 

[R4BOE]

Where can we find it on the forum I=p/u would be mega handy !

 

[i=p/u]

hmm not you got me blood pumping, ''now where did i come across that..

 

[i=p/u]

i think its a sticky...

 

[i=p/u]

http://www.electriciansforums.net/e...ulations/23288-can-we-use-armour-swa-cpc.html here, i was shown how to do it from the regs book and is real easy

 

[jamie-spark]

Thats as a cpc mate not a bonding conductor

 

[R4BOE]

hi thanks for the chart

I=P/u but that chart is for the use with armouring as a CPC not a bonding conductor, as a bonding conductor the copper equivelent is less as that shown on this chart chart on the forum, i think it is to do withy the resitivity of the steel etc a bonding conductor the csa must be 8 times the value of the Copper equivelent thesfore a 10mmsq copper bond requirews the armouring to be 80mm steel CSA, see the top of page 42 of GN8 as this is where this is stated !

if you have access to it the electrical saftey council techincal manual A 57-21 goes into the subject in some depth