Design feedback

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moresi

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Looking for some feedback on a supply system that I am designing for a project. Our firm is not typically a design build firm but given the fairly simple nature of this project I figured we would design in-house. Just looking to see if anything jumps out as an NEC violation to anyone.

Scenario - Have a 400 amp UG meter pedestal remote mounted with 2 - 200 amp MB's 120 / 240 single phase service. We are supplying a Main lodge building, a maintenance shop and 2 small out buildings used for material processing. Feeders off of meter pedestal both enter into basement of main lodge where 1 feeder hits a 200 amp fused disconnect switch at point of entrance and then goes on to hit a 200 amp non-service rated generator ATS and then main lug 200 amp panelboard to supply circuits in that building. Other feeder hits a 150 amp fused disconnect switch and then is piped through basement of lodge exiting basement - serves no loads in that building, continues on to maintenace building. At maintenance building feeder hits a 150 amp non-fused safety switch inside building at point of entrance then a 200 amp non-service rated generator ATS then a 150 amp main lug panel to serve loads in that building. Also off this panel is a 100 amp feeder to another outbuilding where a 100 amp Main Breaker panel is served inside building at point of entrance of conductors. Another smaller building is also served off of the 150 amp panel where a 6 circuit panel board is located. Ground conductors run with all feeders and rods and / or concrete encased electrodes at all buildings. Long pulls of wire but I believe I have this design as compliant.

Thanks
 
electrofelon

electrofelon

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Location
Cherry Valley NY, Seattle, WA
moresi said:
Looking for some feedback on a supply system that I am designing for a project. Our firm is not typically a design build firm but given the fairly simple nature of this project I figured we would design in-house. Just looking to see if anything jumps out as an NEC violation to anyone.

Scenario - Have a 400 amp UG meter pedestal remote mounted with 2 - 200 amp MB's 120 / 240 single phase service. We are supplying a Main lodge building, a maintenance shop and 2 small out buildings used for material processing. Feeders off of meter pedestal both enter into basement of main lodge where 1 feeder hits a 200 amp fused disconnect switch at point of entrance and then goes on to hit a 200 amp non-service rated generator ATS and then main lug 200 amp panelboard to supply circuits in that building. Other feeder hits a 150 amp fused disconnect switch and then is piped through basement of lodge exiting basement - serves no loads in that building, continues on to maintenace building. At maintenance building feeder hits a 150 amp non-fused safety switch inside building at point of entrance then a 200 amp non-service rated generator ATS then a 150 amp main lug panel to serve loads in that building. Also off this panel is a 100 amp feeder to another outbuilding where a 100 amp Main Breaker panel is served inside building at point of entrance of conductors. Another smaller building is also served off of the 150 amp panel where a 6 circuit panel board is located. Ground conductors run with all feeders and rods and / or concrete encased electrodes at all buildings. Long pulls of wire but I believe I have this design as compliant.

Thanks
Click to expand...

It seems ok to me, although I could see doing it with less equipment. I dont see what purpose the 150 amp switch in the first building does, unless you are reducing wire size and cant meet a tap rule. My second thought - and you may be ahead of me on this - is whether you can use the transfer switches as your building disconnecting means thus eliminating those two disconnects. What Im not sure of so you or someone else will have to check me, is even though these are clearly feeders and not service conductors, I remember something about the disconnecting means for a structure having to be service rated, so maybe you need the disconnects ahead of the ATS since you say the ATS are not service rated?
 
Smart $

Smart $

Esteemed Member
Location
Ohio
electrofelon said:
...I remember something about the disconnecting means for a structure having to be service rated, so maybe you need the disconnects ahead of the ATS since you say the ATS are not service rated?
Click to expand...
See below...

225.31 Disconnecting Means. Means shall be provided
for disconnecting all ungrounded conductors that supply or
pass through the building or structure.

....

225.36 Suitable for Service Equipment. The disconnect-
ing means specified in 225.31 shall be suitable for use as
service equipment.

Exception: For garages and outbuildings on residential
property, a snap switch or a set of 3-way or 4-way snap
switches shall be permitted as the disconnecting means.
Click to expand...
 
Smart $

Smart $

Esteemed Member
Location
Ohio
electrofelon said:
Yup ok. Guess it would have been worth the walk out to the truck in the rain to grab the codebook;)
Click to expand...
But since you did not, you are not worthy of true fanatic status, and hereby stripped of all rank and privileges.. :lol:

don't remember pass thru conductors needing a disconnect
Click to expand...
They don't... but a purely bad design without.
 
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moresi

Member
Thanks All-
One final question. Regarding the maintenance shed. This is a 2 bay garage structure which will be for storage of tractors, tools, 4 wheelers, etc. for maintaining the grounds. No work on vehicles except for perhaps the lawn mowers and 4 wheelers. My plans call for wiring all interior receptacles and lighting in EMT to regular steel boxes and raised covers. All GFCI protected receptacles. Would you agree that this method is acceptable for the given use of this building?
 
Smart $

Smart $

Esteemed Member
Location
Ohio
augie47 said:
Would the original set-up not be a violation of 225.30
Click to expand...
Any particular portion of the set-up?

If you are referring to the second feeder... it does not supply the main building... simply passes through on its way to another.
 
M

moresi

Member
If I am reading the text of the code correct there should be no issue nor need for me to run the plan to have the other feeder running through basement of primary building. Both sets entering building have their disconnects grouped together at point of entrance and the running of the second feeder, as long as it serves no loads in that building, is compliant with the NEC. How can this not be accepted? Regarding the ATS - the models we are using are service rated however I for one do not like the design where the means for disconnect are located inside the switch. The first building has a disco. where the feeder enters and then the electrical room is about 60' feet away. The second building all enters and ATS are at same point however I prefer to see a very simple obvious disconnect switch there. For the small cost I found it to make more sense. I am just not a fan of the ATS disconnect means for the model we are using.

Finally - the main lodge is a true log cabin - commercial use single story with an attic. Can anyone make an argument for not using Romex here but rather MC? Just curious.
 
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