Testing extraneous conductive part

[Ian1981]

but in those cases, the "suspect" metal is already bonded due to it being bolted/welded/etc. to the bonded extraneous parts.

No it maybe earthed by being in contact with exposed parts but not necessarily bonded which is different

 

[telectrix]

No it maybe earthed by being in contact with exposed parts but not necessarily bonded which is different

earthed if connected to exposed conductive parts, but bonded if connected to already bonded extraneous parts.

 

[Ian1981]

earthed if connected to exposed conductive parts, but bonded if connected to already bonded extraneous parts.

Something like that ha
I’ve always gone down the route of testing it with the installation isolated, earthing conductor disconnected from the earthing terminal in the CU but connected to the means of earthing,then from the disconnected earthing conductor to the suspect metal.
In practice tho I’ve only ever done this at a domestic level, a commercial or industrial installation already in service, I find is impossible to do the test.

 

[Midwest]

Here's something I've read, they might be wrong of course.
SO HOW DO WE MEASURE IT?

And Does Metallic Cable Tray Require Bonding? - https://professional-electrician.com/technical/bonding-time/

 

[ipf]

earthed if connected to exposed conductive parts, but bonded if connected to already bonded extraneous parts.

Like in a factory, say, where you have the bonded main steel structure and take off a bond for any other required...

 

[Ian1981]

Here's something I've read, they might be wrong of course.
SO HOW DO WE MEASURE IT?

And Does Metallic Cable Tray Require Bonding? - https://professional-electrician.com/technical/bonding-time/

Yeah i would that’s fair enough as long as you haven’t earthed the tray by ways of fixing exposed conductive parts to it or say fixed the tray to steel which has metallic conduit fixed to it also, this would then earth all metallic parts concerned, so it wouldn’t be easy to test to see if it was extraneous ( which I can’t see how it would be in most circumstances)

 

[telectrix]

Like in a factory, say, where you have the bonded main steel structure and take off a bond for any other required...

Egggsackly. free range. ( 3 friggin' words)

 

[Midwest]

Yeah i would that’s fair enough as long as you haven’t earthed the tray by ways of fixing exposed conductive parts to it or say fixed the tray to steel which has metallic conduit fixed to it also, this would then earth all metallic parts concerned, so it wouldn’t be easy to test to see if it was extraneous ( which I can’t see how it would be in most circumstances)

And the other one?

 

[Ian1981]

And the other one?

Same principle, as long as you haven’t earthed it.

 

[Midwest]

Hmmm, I think your wrong about this concept. The principal of the test is simple; no one mentions disconnecting anything.