Use of Isolator Switch on a Live Plant
Use of Isolator Switch on a Live Plant
(OP)
Hi,
This question is related to a site in the UK.
I designed electrical power supplies for the site security swiping system. Some of the supplies were for control panels and auxiliaries 300m away from the power source.
I always include local isolation in my design for electircal consumers located exeternally in plant however in this instance I have been asked if the isolators can be removed. I am not confortable with this and want to back the intent up with an IEC or BS standadrd.
Does anyone know the applicable standard(s) for use / selection of electrical isolator switches please.
This question is related to a site in the UK.
I designed electrical power supplies for the site security swiping system. Some of the supplies were for control panels and auxiliaries 300m away from the power source.
I always include local isolation in my design for electircal consumers located exeternally in plant however in this instance I have been asked if the isolators can be removed. I am not confortable with this and want to back the intent up with an IEC or BS standadrd.
Does anyone know the applicable standard(s) for use / selection of electrical isolator switches please.






RE: Use of Isolator Switch on a Live Plant
I don't think you'll find anything in UK law which makes a local isolator mandatory - the law requires a means to provide safety from the system, a phrase which has specific meaning in law, but the law does not define how to achieve safety from the system. In this respect the law really isn't much help.
RE: Use of Isolator Switch on a Live Plant
For general guidance, I suggest that you look at HSE Electricity at Work : Safe Working Practices on the following link.
http://www.hse.gov.uk/pubns/priced/hsg85.pdf
Download is free
Isolation is not the only issue, there must be a safe system of work, risk assessments, permits to work etc etc
RE: Use of Isolator Switch on a Live Plant
(OP)
1. " I am not comfortable with this and want to back the intent up with an IEC or BS standard. "
I suggest you may look up the following documents on this matter:
a) BS 7671 : 2008 Clause 537.2.2.5 , or later editions, and
b) IEC 60364-5-53 :2002 Clause 536.2.1.2 and Clause 536.2.2.6 , or later editions.
2. Please inform me if the above mentioned documents are not available in your location.
I am able to furnish the [full text of the above clauses] from both Standards.