Electric distribution to home and shop.

[GPintheMitten]

I've been going through something very similar at my daughters farm. She currently has a 200 amp service to the house and needs another 200 amps for the new barns and other farm usage.

After considering various options she is going with a 320 meter splitting into 2 200 amp feeders one for existing house and the other for the barn. It will require a disconnect (200 amp breaker) for each at the meter with ground and neutral bonded there.

Then running three 4/0 aluminum wires and 2/0 ground to each panel. The neutral and grounds will need to be separated in the existing panel (a pita) and unbonded. Then similarly floating the neutral on the new subpanel in the barn.

Her pole and transformer is about 100 feet from her house with underground service cables -- aluminum 2/0.

We considered putting the 320 meter near the pole but elected not to for a couple of reasons. We won't be able to use the existing wire because they are undersized 2/0 aluminum and only 3 wires. We would need to replace all that with 4/0. And she has an interuptable meter for central air that would have to have been moved out next to the 320 meter with its wires. Then there would be the siding issues after removing the meter boxes.

Her power company said no meters on the actual pole. They want 5 foot clearance around the pole in case they need to climb the pole. If we put the meter near the pole it would be on unistrut with 2 inch steel pipe supports - no treated lumber.

Also the electric company was very clear about the need to get a 320 meter approved for their specific company.

 

[countrybumpkin]

Thanks for all the ideas and info, I was sitting around over the weekend and had a lot of time to think of possible ways of getting electric to the new shop with as little trouble as possible. First thing I have to do is run by the local coop office and find out what they will require. Hope to do this in the next few days, I'll post what I find out.

 

[GPintheMitten]

Country, after reviewing your original post, I would be inclined to put a 320 meter at or near your transformer pole. See what your local electrical inspector requires. I believe that NEC normally allows you to put the first disconnect at each building. If he allows this, then the ground is established at each panel and is bonded to the neutral.

In my case my inspector said that this was allowed in Michigan in the past but not currently. So for my daughter's installation we need a disconnect at the meter for each 200 amp feeder to the two panels which are then subpanels. So in addition to checking with your coop, check with your local inspector.

 

[countrybumpkin]

Ok thanks, other than the coop we have no inspectors or codes.

 

[GPintheMitten]

Ok thanks, other than the coop we have no inspectors or codes.

No inspector is odd. Maybe the coop inspects? I suspect that you are governed by NEC.

 

[MossRoad]

Install a new meter base and the Reliance transfer switch at the pole. Just cap the now unused meter base at the house. Auto start generators recommended would be Air Cooled Series | Cummins or KOHLER Generators | 20RESAL with Automatic Transfer Switch | Generators | Products | Home Generators. Generac is much improved from years ago with the direct drive units instead of the vertical shaft belt driven gen sets.

He most likely won't be allowed to do that.

 

[MossRoad]

You shuold also find out how much upgrading to 320 service will cost you in both monthly fees and new/upgraded equipment. Unless you are putting a business or massively electrical shop in, there's usually no need for that much service at a residence. It is a rare day that you will be pulling that many amps in both the house and shop at the same time. I only have 100 amp service. I have heat, air, lights, welders, aircompressors, etc.... all them modern things we all enjoy. :laughing: I've yet to pop a breaker.

Anyhow, what loads are you planning to put in your shop? Is more than one person going to be operating any high powered equipment in there at the same time? Are you ever going to be pulling close to 200 amps at any one time? Add up your loads in your house and what you think they'll be in your shop. Are you really going to be running the equivelent of 15 cdentral air conditioners and a few well pumps at the same time? Probably not.