NEC & Transfer Switch mounting

[Dave Morrison]

I am adding a standby generator to my house and have a question about mounting the auto transfer switch. Here is the background, my power enters overhead down a 2" rigid metal conduit into a meter base from there it continues down into a second box with a 200A main breaker service disconnect in it, then it enters a PVC conduit that continues to the ground and runs underground into the house and to the circuit breaker distribution panel. I am putting in a ASCO 200A auto transfer switch in a NEMA 3R enclosure.

Now for the question. The easiest place to mount the switch will be under the main disconnect (just cut the PVC conduit and mount the switch inline). If I do this, the conduit will exit the transfer switch box at 6" to 9" above ground level. Can the top of the conduit and the bottom of the switch box be this close to the ground??? If this won't fly I'll have a few more questions. Dave in Tucson

[HaHaHa]

I don't think it will fly.

(c) Wiring Design and Location. Emergency wiring circuits shall be designed and located to minimize the hazards that might cause failure due to flooding, fire, icing, vandalism, and other adverse conditions.

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[Roy Mottola]

[Dave Morrison]

I am adding a standby generator to my house and have a question about mounting the auto transfer switch. Here is the background, my power enters overhead down a 2" rigid metal conduit into a meter base from there it continues down into a second box with a 200A main breaker service disconnect in it, then it enters a PVC conduit that continues to the ground and runs underground into the house and to the circuit breaker distribution panel. I am putting in a ASCO 200A auto transfer switch in a NEMA 3R enclosure.

Now for the question. The easiest place to mount the switch will be under the main disconnect (just cut the PVC conduit and mount the switch inline). If I do this, the conduit will exit the transfer switch box at 6" to 9" above ground level. Can the top of the conduit and the bottom of the switch box be this close to the ground??? If this won't fly I'll have a few more questions. Dave in Tucson

[m Ransley]

Flooding by a simple pipe breaking could cause problems, why risk a nice unit by placing it so low.

[Greg]

he said 6" to 9" from grade to the bottom of the can. That must be a heluva pipe you are thinking of that can flood the yard to 6" deep. I like the other solution of a gutter and mounting it at the disconnect height for elegance but that probably means another set of splices in the system (from the existing feeder) or pulling in a new 200a 4 wire feeder.

[Dave Morrison]

That pretty well sums up my problem the other solutions would involve splices between the main disconnect and the breaker panel (is that a code issue in itself???) or pulling 60+ feet of new wire. Flooding is not much of an issue in this area, if I have 6" of water at this location someone's loading up an ark. So for the real question: is there a specific code reference to having the conduit with the main feeds to my house end so close to ground level? Thanks, Dave in Tucson

[Greg]

No, not NEC anyway. If there are no breakers in there there are no maximum heights either.