Shower Cable in wall

[EFLImpudence]

TBH. something pulled out of GN3 which I now can't find.

0.05Ω in GN3 is the accepted value for negligible impedance so would be more the result of bonding rather than the need for it.

 

[Electrifying]

Have you a test/multimeter?

If, from your main earth terminal (usually in the CU) to structural metalwork (pipework) has a resistance of greater than 22ohms then 'earthing' is not required.

John, this statement is 10 x worse than the one about the '0.05' ........you're slipping.

And 'Scoby_Beasley', you really need to make sure of your facts before posting advice.

 

[JohnW2]

0.05Ω in GN3 is the accepted value for negligible impedance so would be more the result of bonding rather than the need for it.

Indeed ....

Hmmm. You seem to be talking about two things that are already very effectively 'bonded'.

Kind Regards, John

 

[JohnW2]

If, from your main earth terminal (usually in the CU) to structural metalwork (pipework) has a resistance of greater than 22ohms then 'earthing' is not required.

John, this statement is 10 x worse than the one about the '0.05' ........you're slipping.

Whoops Indeed! I confess that, in haste, I read that at 22kΩ - which didn't sound too far off the mark.

And 'Scoby_Beasley', you really need to make sure of your facts before posting advice.

Very much so - that was crazy 'advice'.

Kind Regards, John

 

[Scoby_Beasley]

Have you a test/multimeter?

If, from your main earth terminal (usually in the CU) to structural metalwork (pipework) has a resistance of greater than 22ohms then 'earthing' is not required.

John, this statement is 10 x worse than the one about the '0.05' ........you're slipping.

And 'Scoby_Beasley', you really need to make sure of your facts before posting advice.

yup that busy finding the ohm symbol, which I didn't I forgot the (capital) K as in 22KΩ

Using an MFT:
I = V / R;
I = 500V / 22000Ω = 0.023Amp

If the fault was on a single phase 230V supply the current that would flow between the conductive parts would be only 0.0115Amp or 11.5 mA. Just above the 'let go' of 10mA.

This is unlikely to give a fatal shock.

 

[EFLImpudence]

I = 500V / 22000Ω = 0.023Amp

It's the other way round.
10mA is used to determine the resistance.

230V / 10mA = 23,000Ω

Never see the point of deducting 1,000Ω for the human body.
It's not going to be 21,999 or 23,001 is it?
More likely to be 240V anyway, so 24,000Ω

 

[Scoby_Beasley]

I = 500V / 22000Ω = 0.023Amp

It's the other way round.
10mA is used to determine the resistance.

230V / 10mA = 23,000Ω

Never see the point of deducting 1,000Ω for the human body.
It's not going to be 21,999 or 23,001 is it?
More likely to be 240V anyway, so 24,000Ω

True. Sometimes my head hurts. Where's my medication???