Clearance Between Building and Switchyard or Substation

[CBryant]

My plant is wanting to add on to one of our main office buildings and we are needing to know how close to our switchyard we can build. The swityard has two transformers that step 138kV power down to 4160V power. I have dug around in the NEC 2014 edition but am not finding any tables or anything that give a required distance. The table that makes the most sense to be me right now is Table 490.24.

Any guidance or direction will be appreciated.

Thanks

 

[Fnewman]

If the switchyard belongs to your POCO, they will have input for you based on their perimeter grounding plan and possibly the original service agreement. To answer more directly, I have seen customer buildings as as close as 4-5 feet from a substation fence. I don't know of any specific code limitations as they would not apply to the POCO anyway.

 

[CBryant]

Thanks for your reply. The yard belongs to the plant and after a little more looking around in the code book the closes thing I could find were tables 110.34(A) and 110.34(E) for clear working space and elevation above working space. Since we have 138kV power coming in it looks like we just need to stay 10 ft ( we have a ground fence around the yard which puts into Condition 2 of the table) away from that bus and there are no lines running over head of where we are wanting to build so we are in the clear there as far table 110.34(E) goes.

Since the fence that surrounds the yard is required to be 15 ft from exposed electrical equipment and meets this requirement (table 110.31) we should be able to build all the way up it, but don't need to get that close fortunately.

Thanks again.

 

[north star]

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CBryant,

Your question regarding the addition onto your
existing building is a Building & Fire Code question.
There are requirements for Fire Dept. access &
clearances, not to mention egress requirements,
...Zoning Ordinances, [ possible ] fire rated wall
assemblies and their proximity to property lines,
and on and on and on.

I strongly recommend that you schedule a meeting
with the AHJ Bldg. Official & Fire Code Official to
discuss your project. :happyyes:


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