200 amp residential service feeding 3 sub panels.

[Dixonchad]

I have a job that is in a rural part of indiana. It has an underground 200 amp base feeding a 200 amp service rated panel mounted adjacent to 200 base mounted on post assembly free standing. I have a pole building 100 amp subpanel inside the building with a 100 amp disconnect on the exterior fed with 4 wire. I also have a barn that is the same exact way. The home has a 200 amp sub panel and also a 200 disconnect mounted on the home 4 wire as well. In summary i have a 12 space service rated panel being fed from the meter base. Then using pass through lugs i feed a 200 amp disconnect exterior of the home then to the 200 amp panel inside the home all 4 wire. I also feed 2 100 amp sub panels from the 12 space pole mounted panel. A home inspector told the home owner i can not feed that many sub panels. If my main 200 amp breaker in the 12 space pole mounted panel feeds everything downstream then the system could not possibly overload. Both barns are lights and outlets minimal load. Home heats with gas 2200 sf. We are never going to need a larger service. Are there codes that would support the allowance of feeding 2 100 amp subs and a 200 amp sub?

 

[kwired]

I have a job that is in a rural part of indiana. It has an underground 200 amp base feeding a 200 amp service rated panel mounted adjacent to 200 base mounted on post assembly free standing. I have a pole building 100 amp subpanel inside the building with a 100 amp disconnect on the exterior fed with 4 wire. I also have a barn that is the same exact way. The home has a 200 amp sub panel and also a 200 disconnect mounted on the home 4 wire as well. In summary i have a 12 space service rated panel being fed from the meter base. Then using pass through lugs i feed a 200 amp disconnect exterior of the home then to the 200 amp panel inside the home all 4 wire. I also feed 2 100 amp sub panels from the 12 space pole mounted panel. A home inspector told the home owner i can not feed that many sub panels. If my main 200 amp breaker in the 12 space pole mounted panel feeds everything downstream then the system could not possibly overload. Both barns are lights and outlets minimal load. Home heats with gas 2200 sf. We are never going to need a larger service. Are there codes that would support the allowance of feeding 2 100 amp subs and a 200 amp sub?

You are correct. There is no limit on how many subpanels you can feed, only how much load you can supply with your 200 amp equipment, and if you are supplying too much load, that is part of what overcurrent protection is about.

 

[david]

A home inspector told the home owner i can not feed that many sub panels. If my main 200 amp breaker in the 12 space pole mounted panel feeds everything downstream then the system could not possibly overload. Both barns are lights and outlets minimal load. Home heats with gas 2200 sf. We are never going to need a larger service. Are there codes that would support the allowance of feeding 2 100 amp subs and a 200 amp sub?

I'm not sure your home inspector has looked at article 547 or 547.9

 

[Dennis Alwon]

I'm not sure your home inspector has looked at article 547 or 547.9

Not sure what 547 has to do with his question.

 

[kwired]

Not sure what 547 has to do with his question.

Maybe can apply but doesn't have to. Bottom line is a 200 amp supply is capable of supplying anything 200 amps or less, even if subdivided into 1000 different sub components.

 

[david]

I have a job that is in a rural part of indiana

It has an underground 200 amp base feeding a 200 amp service rated panel mounted adjacent to 200 base mounted on post assembly free standing.

In summary i have a 12 space service rated panel being fed from the meter base. Then using pass through lugs i feed a 200 amp disconnect exterior of the home then to the 200 amp panel inside the home all 4 wire. I also feed 2 100 amp sub panels from the 12 space pole mounted panel

Not sure what 547 has to do with his question.

Dennis he has a pole service with feed through lugs to a disconnect to the house, the pole service feeds a pole building and a barn and his house.
It just sounds like most central distributions I see on farms all over this part of PA.

The make up of the supply to these additional buildings has a lot to do with what the home inspector is calling sub- panels from this distribution point

My point is it not only compliant but very common on farms

 

[Dixonchad]

Are there any codes that could help me support this installation meets the minimum of code?

 

[david]

Are there any codes that could help me support this installation meets the minimum of code?

The language in this sections sets up the supply to the buildings to be what he is calling sub-panels (feeders)
547.9 Electrical Supply to Building(s) or Structure(s) from a Distribution Point.
(C) Service Disconnecting Means and Overcurrent Protection at the Distribution Point. Where the service disconnecting means and overcurrent protection for each set of feeder conductors are located at the distribution point, feeders to building(s) or structure(s) shall meet the requirements of 250.32 and Article 225, Parts I and II.

As far as if the service or feeder is not large enough the home inspector should explain why it is not especially if non of your feeders or service over current protection is tripping

Edit: if your utility is kind, they may give you a read out over a six month period of what your usage has been

 

[kwired]

Are there any codes that could help me support this installation meets the minimum of code?

Do load calculation according to art 220. If you are under 200 amps nothing wrong with what you have.

 

[infinity]

Do load calculation according to art 220. If you are under 200 amps nothing wrong with what you have.

I agree, this is not complicated and unless the home inspector actually did the calculation he has no idea if the 200 amps is adequate or not. Regarding the number of sub-panels he just wrong.

 

[Dennis Alwon]

I would ask the home inspector to back up his claim and do a calculation. The only way he can confirm what he says is to do a calculation. As stated many times you can have 100 subpanels as long as the load is not greater than the service disconnect

 

[winnie]

If my main 200 amp breaker in the 12 space pole mounted panel feeds everything downstream then the system could not possibly overload. Both barns are lights and outlets minimal load. Home heats with gas 2200 sf. We are never going to need a larger service. Are there codes that would support the allowance of feeding 2 100 amp subs and a 200 amp sub?

You system _might_ be overloaded and thus a violation.

As kwired said: do an article 220 calculation. If the number comes out above 200A, for all of the structures fed by the 200A panel, then per code it is overloaded.

It is known that article 220 gives high results, meaning that if you calculate out (say) 250A then in reality the load will probably be less than 200A...but if the calculation gives you more than 200A then the service is 'officially' overloaded.

There is no limit on the number or size of the 'subpanels' fed from this 200A service. You could have an 800A panel at each of the 3 buildings fed from the 200A service, and be totally kosher. All that matters is the calculated load.

-Jon

 

[david]

You system _might_ be overloaded and thus a violation.

As kwired said: do an article 220 calculation. If the number comes out above 200A, for all of the structures fed by the 200A panel, then per code it is overloaded.

It is known that article 220 gives high results, meaning that if you calculate out (say) 250A then in reality the load will probably be less than 200A...but if the calculation gives you more than 200A then the service is 'officially' overloaded.

There is no limit on the number or size of the 'subpanels' fed from this 200A service. You could have an 800A panel at each of the 3 buildings fed from the 200A service, and be totally kosher. All that matters is the calculated load.

-Jon

I would make the OP aware of his options since this is an existing installation

220.87 Determining Existing Loads.
The calculation of a feeder or service load for existing installations shall be permitted to use actual maximum demand to determine the existing load under all of the following conditions:

V. Farm Load Calculations
220.100 General.
Farm loads shall be calculated in accordance with Part V.