Service disconnect grouping question

[P.A.Lin-Z]

I have a huge house that we are wiring.
There are 3–200-amp single phase panels in separate location throughout the house.
The service is NOT attached to the house and is located about 150 feet in front of the house by the driveway in the location of the transformer.
There will be a CT meter, a CT junction box, and 3–200-amp service rated ATS's for a generator system.
Will there still have to be service disconnects grouped and located on the house? We are currently under 2017 NEC.

 

[don_resqcapt19]

It appears that the transfer switches are the service equipment. That means you are supplying the house with 3 feeders and that would be a violation of 225.30.

 

[paullmullen]

@don_resqcapt19, wouldn't 225.30(B)(2) apply?


I'm not totally sure what 225.30(E) means by "Documented Switching Procedure", but does that open another hole in the base 225.30 requirement?

Also, a note that some jurisdictions may have different rules. In Wisconsin SPS316.225(2)(a) modifies 225.30 to redefine Number of Supplies.

 

[jaggedben]

I was going to say that in my opinion 600A is not big enough to invoke that section, but I guess Wisconsin disagrees. It's an AHJ call if there is no similar local ammendment at the relevant location.

 

[packersparky]

@don_resqcapt19, wouldn't 225.30(B)(2) apply?
View attachment 2572448

I'm not totally sure what 225.30(E) means by "Documented Switching Procedure", but does that open another hole in the base 225.30 requirement?

Also, a note that some jurisdictions may have different rules. In Wisconsin SPS316.225(2)(a) modifies 225.30 to redefine Number of Supplies.

View attachment 2572449

The OP stated that the feeders were located at different locations throughout the house, so it would not be compliant with that section of SPS 316.

 

[P.A.Lin-Z]

@don_resqcapt19, wouldn't 225.30(B)(2) apply?
View attachment 2572448

I'm not totally sure what 225.30(E) means by "Documented Switching Procedure", but does that open another hole in the base 225.30 requirement?

Also, a note that some jurisdictions may have different rules. In Wisconsin SPS316.225(2)(a) modifies 225.30 to redefine Number of Supplies.

View attachment 2572449

It comes down to AHJ and his interpretation. some jobs need to be designed a different way. In my case because the house is so spread out there will be voltage drop issues. I'm trying to eliminate that by having panels in their specific areas.

 

[roger]

It comes down to AHJ and his interpretation. some jobs need to be designed a different way. In my case because the house is so spread out there will be voltage drop issues. I'm trying to eliminate that by having panels in their specific areas.

There could still be grouped disconnects for the panels on the exterior of the house. In my experience multiple services or feeders to different locations and not grouped were in buildings that were acres under roof. The written procedures were for maintenance staff and emergency personnel.

 

[paullmullen]

The OP stated that the feeders were located at different locations throughout the house, so it would not be compliant with that section of SPS 316.

I believe you, but I don't see the "different locations" language in SPS316. Teach me?

 

[P.A.Lin-Z]

They want me to group disconnects at both locations....citing 225.30.
I am going to put the monstrosity on the house and bring the utility to the house because that's what the government needs more than the will of the homeowner.
I can't take the risk of having two different groupings of disconnects.

 

[electrofelon]

They want me to group disconnects at both locations....citing 225.30.
I am going to put the monstrosity on the house and bring the utility to the house because that's what the government needs more than the will of the homeowner.
I can't take the risk of having two different groupings of disconnects.

What about shifting gears a bit and using a single 400 or 600 A ATS and then a MLO distribution panel on the side of the house with three 200 amp breakers to serve your subs? Probably be less equipment and a little smaller and cleaner overall.

 

[Elect117]

What about shifting gears a bit and using a single 400 or 600 A ATS and then a MLO distribution panel on the side of the house with three 200 amp breakers to serve your subs? Probably be less equipment and a little smaller and cleaner overall.

I was going to ask why 3 ATSs were necessary.

Similarly,

Why not hit the one ATS then use the parallel 3/0s or higher wire size, then a wire way with a tap, polaris taps or something, to 3 fused DCs that are grouped. Then go to the 3 sub panels?

 

[P.A.Lin-Z]

I was going to ask why 3 ATSs were necessary.

Similarly,

Why not hit the one ATS then use the parallel 3/0s or higher wire size, then a wire way with a tap, polaris taps or something, to 3 fused DCs that are grouped. Then go to the 3 sub panels?

There is no room on the house and the customer doesn't want anything utility wise on the house. The customer doesn't want a 600 amp service with a CT cabinet on the house and because of the design and size there's no place for a service that large and there's also voltage drop issues with feeders that long.
One of the ATS's was going to be a feed thru so we could put a well and a barn out at the transformer location which is the location of the natural gas and the generator.

 

[jaggedben]

Funny, you said the house was huge...

When clients want things that aren't code compliant I tell them they can't have it, or if something is borderline at least that there needs to be a Plan B. You need grouped disconnects.


Also I don't think you really read Elect117's suggestion carefully, he didn't suggest bringing the service to the house. And that bit about voltage drop does not seem to make any sense.

 

[packersparky]

I believe you, but I don't see the "different locations" language in SPS316. Teach me?

The language you cited in SPS 316 requires the disconnects to be grouped at the same location.

 

[P.A.Lin-Z]

They are grouped in the same location and now there will be two groups of disconnects.

 

[P.A.Lin-Z]

Funny, you said the house was huge...

When clients want things that aren't code compliant I tell them they can't have it, or if something is borderline at least that there needs to be a Plan B. You need grouped disconnects.


Also I don't think you really read Elect117's suggestion carefully, he didn't suggest bringing the service to the house. And that bit about voltage drop does not seem to make any sense.

Well dang, I should've consulted with you to begin with.

 

[P.A.Lin-Z]

Funny, you said the house was huge...

When clients want things that aren't code compliant I tell them they can't have it, or if something is borderline at least that there needs to be a Plan B. You need grouped disconnects.


Also I don't think you really read Elect117's suggestion carefully, he didn't suggest bringing the service to the house. And that bit about voltage drop does not seem to make any sense.

The disconnects are grouped, now there are two groups of disconnects.

 

[david]

They want me to group disconnects at both locations....citing 225.30.
I am going to put the monstrosity on the house and bring the utility to the house because that's what the government needs more than the will of the homeowner.
I can't take the risk of having two different groupings of disconnects.

If this house has a basement, I'd grouped the disconnects in the basement and give the owners what they want as far as the clean look on the outside of there very expensive house.

It would also make bonding the grounding electrode system cleaner looking in the basement.

You didn't say it but I imagine one of your distribution panels in your planning was going to be in the basement alresdy.

 

[P.A.Lin-Z]

There's no basement. The service is going to be 180 feet from the front of the house. There are 3 different 200-amp panels in the house. The house is one floor and is spread out 150 feet wide and is shaped like a U and is about 130 feet deep from front to back. Panel "A" is on the left side of the housed to serve the main kitchen, a dirty kitchen, laundry, and front garage area. Panel "C" is in the rear wing of the left side and is serving a 3-care garage, playroom, pool equipment, a/c equipment, a pet grooming wash down area, and about 1500 sq feet upstairs. Panel "B" is 140' in the other direction and is serving the master bedrooms, master bath, huge living area, other bedrooms, a/c units on that end and two sunrooms, etc.
The main electrical service will be 3–200-amp SER Transfer switches with one of them being a Load center type ATS to serve the well and then feed panel "B' in the house.
the main service is grouped and will be a 600-amp CT meter. There will be a second group of disconnects at the house where the panel feeders enter the house. No basement.

 

[jaggedben]

And we have explained why that design's compliance with the NEC is questionable. If it doesn't pass inspection don't blame us, we're just trying to help.

Again, why not parallel the three 200A feeds into a single 600A feeder to the house on a single ATS, and then tap that to three 200A disconnects which then feed the subpanels? You seem to have described something like 430ft of house perimeter on three sides and you're saying that nowhere in those hundreds of feet is there a >6ft wide space for three 200A disconnects or breaker enclosures? I mean, I also hate it when the architects don't think of necessities but part of my job is to tell people what's needed for a compliant installation.