How do you test main bonding when it's several meters long?

[Capn Ahab]

CU in hallway, water pipes into house are out the front door and round the other side of the house. Probably a 6 -7m main bonding conductor.

a) Is this safe?

b) Is there a way of testing it without using really long leads?

Cheers,

Ahab

 

[jonnyboy1]

a wander lead connected from met out 2 pipe

bingo

 

[IQ Electrical]

CU in hallway, water pipes into house are out the front door and round the other side of the house. Probably a 6 -7m main bonding conductor.

a) Is this safe?

b) Is there a way of testing it without using really long leads?

Cheers,

Ahab

You answered your own question, you use an R2 long lead test to ascertain the resistance of the bonding conductor.

This should be within approximately 0.05 Ohms

Your 'is it safe' question is quite surprising, what experience do you have?

 

[telectrix]

long lead. null leads with long lead in circuit. test bond, job done

 

[Concept]

Yes basically "method 2 - R2" we had to do this in an old peoples home when it was empty, just make sure you null the whole lead.

 

[tonys]

Unless you can physically trace the cable, then you should really isolate the supply to the installation in question and disconnect the cable at both ends and then carry out the continuity test.

This is only my opinion, so please don't take it literally as being correct.

 

[Concept]

lol that why I said it was empty because we had to disconnect the supply which we made sure it was safe to do.

 

[IQ Electrical]

Unless you can physically trace the cable, then you should really isolate the supply to the installation in question and disconnect the cable at both ends and then carry out the continuity test.

This is only my opinion, so please don't take it literally as being correct.

Just for 2391-10 students, the installation should always be isolated when testing main protective bonding conductors.
The method in Guidance Note 3 recommends the disconnection of one end of the conductor to avoid parallel paths.

 

[Capn Ahab]

Your 'is it safe' question is quite surprising, what experience do you have?[/QUOTE]

Thanks for the answer. I suppose it was a bit of a dumb question with hindsight as a little thought process would tell me that as long as the ohms are low enough it is safe. What I meant was, since I don't know anything other than the 17th ed, is there anything that was allowed in previous editions of the regs that wouldn't be now, e.g. Is running the main bonding conductor along the outside of the house acceptable? I'm just starting out to be honest and want to get things right, but don't know the BRB back to front yet.

Thanks to all for the surprisingly quick answers BTW.

 

[tonys]

Just for 2391-10 students, the installation should always be isolated when testing main protective bonding conductors.
The method in Guidance Note 3 recommends the disconnection of one end of the conductor to avoid parallel paths.

I disconnect it at both ends to identify as well as the continuity test so I can cable tie a tag displaying the words Gas or Water or Steelwork and that's in all honesty and that was a requirement of the nic for a new install so I used to carry it out on remedials while carrying out pirs.

 

[IQ Electrical]

Your 'is it safe' question is quite surprising, what experience do you have?

Thanks for the answer. I suppose it was a bit of a dumb question with hindsight as a little thought process would tell me that as long as the ohms are low enough it is safe. What I meant was, since I don't know anything other than the 17th ed, is there anything that was allowed in previous editions of the regs that wouldn't be now, e.g. Is running the main bonding conductor along the outside of the house acceptable? I'm just starting out to be honest and want to get things right, but don't know the BRB back to front yet.

Thanks to all for the surprisingly quick answers BTW.[/QUOTE]

It's unusual, the bond is normally carried out at the point of entry to the building.

 

[telectrix]

as long as the cable is not prone to be damaged, no problem. any chance of mechanical damage, it should be protected in conduit. are there hungry squirrels about the property?

 

[Capn Ahab]

Nah, just crack squirrels!

 

[ukpablo]

yes, running it outside of the house is accectable too!

 

[Des 56]

The outside cable can be made squirrel proof by

A, Enclosing the cable in conduit or
B, Make sure the squirrel has an abundance of nuts or
C, Buy a cat