earthing conductor csa

[martinxxxxxx]

I don't believe that BS7671 allows you to determine the size of THIS conductor by calculation.As the regs only refer to calculating the main bbonding conductors.
Agreed?

 

[davelx]

543.1.1 The cross sectional area of every protective conductor, other than a protective bonding conductor, shall be:

i) calculated in accordance with Regulation 543.1.3, or

(ii) selected in accordance with Regulation 543.1.4

and reg 544.n which deals with Protective Bonding Conductors makes no provision for calculating their size - it is prescriptive.

so, no, don't agree - I think it's the other way round!

 

[Spark123]

PME has additional requirements too, see 542.3.1

 

[martinxxxxxx]

543.1.1 The cross sectional area of every protective conductor, other than a protective bonding conductor, shall be:

i) calculated in accordance with Regulation 543.1.3, or

(ii) selected in accordance with Regulation 543.1.4

and reg 544.n which deals with Protective Bonding Conductors makes no provision for calculating their size - it is prescriptive.

so, no, don't agree - I think it's the other way round!

OK I see that - I needed to check the definition of Earthing COnductor first though so if it results in less that 6mm, would you be content to leave a 6mm Earthing Conductor or would you upgrade and if so why

 

[GaryMo]

If you prove by calculation that a 6mm2 earthing conductor is sufficient then there's no need at all to to replace it with a larger conductor.

If you're unsure about using the adiabatic equation correctly then install a larger conductor!

 

[martinxxxxxx]

Interesting, I have no problem with that simple calc. But I wonder if I feel comfortable with just a 6mm conductor as the main tie to earth

 

[GaryMo]

Even if it's sufficient with the British Standard we work to?

 

[martinxxxxxx]

I think that is whst i said