320A Electrical service - workshop and house

[sfelter1]

I am in the process of building a new home and separate workshop. I am coming across issues when figuring out how to run the wiring due to location the power is coming onto the lot. It will be less than 100 feet to the garage but approximately 350' to the house.

Utility service Poles will be feeding transformer (pole mount).
I have a couple options and would like to get feedback on the best option from others experienced with this more than I.

I believe I can:
1)mount the meter remotely - close to the utility pole and run each service from there.
2) mount on garage and split out from there
3) Mount meter remotely closer to the house within 100' and garage would be close to the same.

Garage and house are in similar directions from where the power will be coming onto the land. Garage is obviously closer to incoming power.

Stipulation with the serving power company, the total capacity of disconnects can not exceed 300A and no buss fusing more than 300A. Only equipment approved is a standalone meter - no combo panels are approved.

The biggest question I have: Is there a way to legally get power from the remote meter to a 200A panel to the house and 100A panel to the workshop?

Would mounting on the workshop make it an easier way to split the power?

Local authority is subject to 2017 NEC

I understand most of the basic requirements for electrical install and they allow homeowners to wire primary homes after a test is taken and passed.


Thanks.

 

[dcg9381]

I have 320A service to my home/shop. In my case, I have 2 x 200A panels (on 320A service) in the yard. One panel feeds the house (200A) and the other panel feeds the shop (100A) and an RV sub-panel (50A).

> Stipulation with the serving power company, the total capacity of disconnects can not exceed 300A and no buss fusing more than 300A. Only equipment approved is a standalone meter - no combo panels are approved.

It sounds like you can't do what I'm doing, as my disconnects total 350A. You could, however, do it as 200A to the shop and then 100A to the shop.... If you put a panel on the house (300A bus) and then sub out to the shop, you're limiting yourself to 300A - which is the max throughput of that bus. I do it with 2 panels - this is what my POC suggests:

 

[mike93lx]

If the garage is on the way to the house, it seems like it would be cheaper to put the meter on the garage and then make the house a subpanel off that.

Is a backup generator a factor here? If you do what I listed above, you can't have the generator at the house and also backing up the shop, if that matters

 

[sfelter1]

I have 320A service to my home/shop. In my case, I have 2 x 200A panels (on 320A service) in the yard. One panel feeds the house (200A) and the other panel feeds the shop (100A) and an RV sub-panel (50A).

> Stipulation with the serving power company, the total capacity of disconnects can not exceed 300A and no buss fusing more than 300A. Only equipment approved is a standalone meter - no combo panels are approved.

It sounds like you can't do what I'm doing, as my disconnects total 350A. You could, however, do it as 200A to the shop and then 100A to the shop.... If you put a panel on the house (300A bus) and then sub out to the shop, you're limiting yourself to 300A - which is the max throughput of that bus. I do it with 2 panels - this is what my POC suggests:

Do you have details of how this was done or pictures of it? I think even if I were to mount on the garage, this would be very similar, just mouting differences.

If the garage is on the way to the house, it seems like it would be cheaper to put the meter on the garage and then make the house a subpanel off that.

Is a backup generator a factor here? If you do what I listed above, you can't have the generator at the house and also backing up the shop, if that matters

If I do a backup generator, it will be at the house and would only keep the necessary power on.

One reason I want to keep the meter closer to the garage is due to the future addition of solar (ground mount) and it would be easier due to open space up by the incoming power pole area.

 

[theoldwizard1]

Would mounting (the meter) on the workshop make it an easier way to split the power?

YES ! Possibly a combination meter pan/load center. What ever load center you use will need a main disconnect (breaker) and then a disconnect (breaker) for the feed to each building load center.

Remember, the POCO need access to the meter.

 

[u2slow]

If the garage is on the way to the house, it seems like it would be cheaper to put the meter on the garage and then make the house a subpanel off that.

Agreed. That's what my folks did at their place. 400A service to the shop, and subfeed 200A to the house.

What I like about the piggyback arrangement is you don't short-change yourself with only 100A at the shop. You have *all* the service capacity there, less what you're actually drawing at the house.

 

[dcg9381]

Do you have details of how this was done or pictures of it? I think even if I were to mount on the garage, this would be very similar, just mouting differences.

That's the spec from my POC. As I built it, yes, I've got additional photos. It's basically a meter panel that has dual lugs that power 2 x 200A panels... PM me if you want the details of how I wired it.

What I like about the piggyback arrangement is you don't short-change yourself with only 100A at the shop. You have *all* the service capacity there, less what you're actually drawing at the house.

I can see doing this using a single 300A capable panel with fed-through lugs. IMHO, 100A at a shop is more than enough for most of us that aren't running fabrication businesses.

 

[kj_mustang]

My main power feed comes to my pole barn, goes to two 200 amp disconnects, one feeds 100 amp panel in barn and also goes to the house, the other disconnect only runs to the house. Have 2 - 200 amp panels in the house.

 

[sfelter1]

My main power feed comes to my pole barn, goes to two 200 amp disconnects, one feeds 100 amp panel in barn and also goes to the house, the other disconnect only runs to the house. Have 2 - 200 amp panels in the house.

I believe this is my best option. That looks pretty clean and simple enough. I thought I read in the NEC about splitting from double lugs to an uneven distribution, but now I think that meant going to one service instead of two in one building.

So with NEC 2017, would I be able to run to meter - split to 200A breaker service entrance and use a through lug type panel to run to the house and then use another 100A interiror panel on opposite side of the mounted meter and feed the workshop from there or do I need to have an external mounted service entrance type shutoff?

Thanks for the help so far everyone. I know I will need to get approval from the local authority, but this gives me a concrete plan to provide them before going to them.

 

[Bopbop]

When I built my new garage I had a new 400 AMP underground service ran to the house. It was the closest to the service. At the house the 400 AMP service was split with (2) 200 amp disconnects. My service looks just like KJ_Mustangs service. ! 200 amp service serves the house and the pump house. The second feeds the shop and the pole barn. It works really good. I can isolate either service. With the hurricanes and power outages i have a sent up so that i can isolate the house and pump house and back feed power from a generator to operate the well and refrigerator and freezer. Now I just need a whole house generator.