Space clearance around MV and LV switchgear

[davva]

Is there a BS or IEC standard that designates the minimum clearances around MV and LV switchgear (indoor switchgear)?The MV gear is 10kV and LV is 380V.

I am used to providing the minimum clearance as designated by the switchgear manufacturer for maintenance etc.

In particular a Chinese client wants to locate a LV switchboard in close proximity to a MV switchboard and has asked the minimum distance between the rear of the LV switchboard (cable compartment) and front of MV switchgear (breaker housing). This is for a land based application in China where there appears to be no such clearance requirements.

My first instincts were not to colocate the two or fence off the MV switchgear in a access controlled area (but that is based on my past life working in the offshore industry).

In the lack of any BS / IEC standard I was going to apply NFPA 70 clearances.

 

[sslobodan]

We usually make 2 rooms separated by wall, but you can pick:
1. Make 2 rooms.
2. make wall between them (Brick wall that would separate them is sufficient
3. 2.5 meters

I would recommend 2 because you are most certainly using something like Siemens closed quarters solution in this one. That means vacuum circuit breakers on 10KV and closed connected cubicles. That facility is safe enough that you can let children play football inside of it. And 0.4 KV side is also enclosed in cubicles so there is no way you can get arc hazard anywhere (all rails are isolated and ETC)

 

[Hoxton]

IEC61936-1 Power Installations Exceeding 1kV applies, but it is very general and reminds you that local rules may apply. I have just read it again, and it does not actually say that HV and LV boards should be in separate rooms, and it just implies that HV switchgear should be in a building. Guidance is given for building construction: aisles to be 800mm wide, for example.

 

[davva]

Thanks sslobodan.

Hoxton, yes I ended up at HD 637 (aka IEC 61936-1) after reading IEC 60204-11 (I thought I was going to get an answer but I should not have got my hopes up!).