minimum clearances distance IEC/BS standards 2

[juanarozo]

What are the designates minimum clearances distance around MV and LV switchgear (indoor switchgear)according with IEC/BS standars?

The MV gear is 11kV and LV is 400V.

 

[ScottyUK]

I suspect if there's an answer in the British standards it will be somewhere in the BS EN 62271 series for HV switchgear, but more probably it will be specified by the manufacturer and likely also by the DNO's own design rules.

You should also review IEC 61936 "Power installations exceeding 1 kV a.c." which definitely contains some clearance and separation information.


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If we learn from our mistakes I'm getting a great education!

 

[Marmite]

I think it's manufacturer specified. For MV switchgear manufacturers quote minimum clearances based on the results of type tests. For example if the operator is stood in front of the gear when it fails catastrophically, all the arc products will be deflected away from the operator usually towards the rear, but to be confident of no arc products coming forwards you would need a specified volume of air at the rear of the gear which would be available for displacement by the arc. The rear clearance and ceiling height would therefore be critical to achieve this.
I did find the following text in the ABB switchgear manual which cites a German DIN standard 0101. "The minimum width of gangways in indoor installations should be 800 mm. For safety reasons these dimensions must not be reduced, not even by projecting parts such as fixed drives, control cabinets, switchgear truck in isolated position. Cubicle doors must slam shut in the escape direction. When the door is open, the gangway width
must still be 500 mm. For service aisles behind metall-enclosed installations; a minimum gangway width of 500 mm is permissible."
Regards
Marmite