Minimum disconnect height, in environments subject to snow

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Carultch

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Is there an NEC requirement about the minimum height of a disconnect, where it is in a region subject to snowfall?

What about readily accessible, in the NEC2014 definition? Does snow count as an obstacle you need to remove, in order to access a device that is otherwise "readily accessible"? What about "within sight"?

I have a situation where NEC690.15 applies to inverters mounted on a rooftop, and the person reviewing my drawings is challenging me on mounting the inverters 2 ft above the finished roof surface.
Certainly they are not "readily accessible" from the ground, but in the event that inverters are not readily accessible from the ground, NEC690.15 requires that the corresponding disconnects be "readily accessible" and "within sight" from the inverters.
 
The NEC has no provisions regarding equipment-of-topic placement in relation to snow accumulation.
 
This is what "readily accessible" means according the the NEC.

Accessible, Readily (Readily Accessible). Capable of being
reached quickly for operation, renewal, or inspections
without requiring those to whom ready access is requisite
to actions such as to use tools, to climb over or remove
obstacles, or to resort to portable ladders, and so forth.
Click to expand...

I think a very good argument could be made that enough snow could be an "obstacle".
 
Smart $ said:
The NEC has no provisions regarding equipment-of-topic placement in relation to snow accumulation.
Click to expand...

Is a device no longer considered "readily accessible" or "within sight" when it is covered in snow? When in summer weather, it is both "readily accessible" and "within sight".
 
Carultch said:
Is a device no longer considered "readily accessible" or "within sight" when it is covered in snow? When in summer weather, it is both "readily accessible" and "within sight".
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There is nothing in the NEC which accounts for seasonal weather changes on the matter. It falls on AHJ interpretation, as you are experiencing, and you'll have no means to challenge it IMO.
 
Smart $ said:
There is nothing in the NEC which accounts for seasonal weather changes on the matter. It falls on AHJ interpretation, as you are experiencing, and you'll have no means to challenge it IMO.
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I'm not actually sure who it is, who is challenging me on this. And I don't have the authority to talk to the AHJ.

So you're telling me, that if I'm in a region where it could snow a height of 7 ft, and the NEC dictates the famous 6'-7" maximum, that this puts it in a Catch 22 where it cannot be installed at this location?

I'm exaggerating to make my point. Obviously there has to be some way of objectively knowing what an acceptable minimum height is.
 
Snow could be an obstacle, but in most temperate regions it's not a predictable one and placement based on the greatest snowfall ever seen in a region would likely make the equipment inaccessible for all other times. In my opinion the only person who should be taking snowfall into account is the engineer determining what the roof load will be.
 
can you mount them immediately adjacent to the inverter? That would appear to make them readily accessible from the inverter and that is what the provision requires.
 
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