Question regarding isolation.

[Davey1988]

I installed a 3 phase distribution panel and i had to prove safe isolation for my NVQ level 3 (working with a qualified electrician)

i only had to isolate one circuit. But theres a small sticker saying main switch isolated before removing cover. This wasn't required to isolate for the job in hand at the time on a separate circuit. Is it against the regs or we to remove the cover with one circuit isolated as i needed to prove isolation.

Cheers guys

 

[Richard Burns]

When you are considering electrical work and levels of isolation you are now coming under the Electricity at Work Regulations 1989.
The key extracts from them are as follows:
Every work activity, including operation, use and maintenance of a system and work near a system, shall be carried out in such a manner as not to give rise, so far as is reasonably practicable, to danger.


No person shall be engaged in any work activity on or so near any live conductor (other than one suitably covered with insulating material so as to prevent danger) that danger may arise unless -
(a) it is unreasonable in all the circumstances for it to be dead; and
(b) it is reasonable in all the circumstances for him to be at work on or near it while it is live; and
(c) suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

The HSE provide guidance on these issues through the leaflets safe working practices, Electrical test equipment for use by Electricians and the Memorandum of guidance on the Electricity at Work Regulations.

The ideal situation is to ensure that all circuits that you will be working on are proved dead and all circuits near which you may be working that have exposed live parts are proved dead. However it is possible in some cases to provide insulating barriers to protect against danger from adjacent live parts. A suitable risk assessment would need to be carried out to ensure that you were not exposed to danger.
Any electrical circuits on which you are working directly must be suitably isolated, locked off and barriers (if applicable) and warning signs erected.

 

[Davey1988]

Cheers richard