Completing electrical certificates

[tomodo]

Hi all, question on testing and completing certificates inside a large factory in maintenance, a lot of the 3P boards here are full of cables, when we are adding to existing circuits, it would be required to perform the necessary tests, R1 R2 and Zs for instance inside the boards, how do we go about this when we are unable to isolate the board, having to open up an old board rammed with cables opens up risks itself. Is there anyway around this or must we be disconnecting from the earth bar every time we work on the circuit. Thanks

 

[Tom256]

Hi all, question on testing and completing certificates inside a large factory in maintenance, a lot of the 3P boards here are full of cables, when we are adding to existing circuits, it would be required to perform the necessary tests, R1 R2 and Zs for instance inside the boards, how do we go about this when we are unable to isolate the board, having to open up an old board rammed with cables opens up risks itself. Is there anyway around this or must we be disconnecting from the earth bar every time we work on the circuit. Thanks

I will offer some initial thoughts.
A workplace so the EAWR 1989 applies, it is statutory and carries legal consequence drawing its authority for regulation from the Health and Safety at Work Act 1974. Mentioned because such is often overlooked and BS7671 is only refered against. You need to have considerations beyond such.

EAWR 1989 R 14 working on or near live parts - There is a duty to ensure a safe system of work is in place therefore have you spoken with the duty holder or electrical authorised person for the LV electrical installation on the site?
Are there any ARC Flash considerations for the DB?

[Most] Industrial sites operate a permit and sanction system to work as part of the safe system of works. Have the authorised person / duty holder agreed a sanction for works to go about this task of working near live parts? EAWR R4 (3) .
It is the duty holder with control over the electrical installation that you need to be having this discussion with.

Out of interest, BS7671 - fundamental principles - what did you do to ascertain that the circuits and distribution are adequate for the alterations before starting work ? reg 132.16 refers .