120/208v 3ph for Residential Service

Status
Not open for further replies.
J

jap

Senior Member
Occupation
Electrician
A client has 480v 3ph at his business and is wanting to build a residence roughly 300' away from his business where he eventually wants to run 3ph equipment in his future shop by the house.

The business and the residence will all be under the same meter.

Is there any issues with servicing the residence with a 3ph 120/208v service and panel in the house being fed off of the 2ndary of a 480/120/208v X-fmr located outside the new residence?

I don't know of any but had to ask for such an interesting installation.

JAP>
 
Strictly speaking from an NEC standpoint, there is no problem with a residence having a 120/208V, 3 phase service.

There may be an issue if the service originates from a separate property lot for the residence versus the business (as pointed out, it may also be a problem to have a residence on commercial property)
 
Just keep in mind the 208 voltage. Will effect your appliances and HVAC.
Depending on what 3 phase equipment he is planning on moving to the house, you may want to put a 480v panel there which might help you reduce the size of your transformer..
 
Dennis Alwon said:
Most power company's do not have 3 phase available for a residence and some will not give it to you either
Click to expand...

The 480v Service is already existing at his business.

He's wanting to build the house behind the business and run it off of his business.


JAP>
 
augie47 said:
Just keep in mind the 208 voltage. Will effect your appliances and HVAC.
Depending on what 3 phase equipment he is planning on moving to the house, you may want to put a 480v panel there which might help you reduce the size of your transformer..
Click to expand...

I agree, but, He was wanting to leave the 480 at the business and the Xfmr at the residence to cut down on the larger low voltage feed to the house.

JAP>
 
Maybe consideration on whether your customer wants to pay commercial rate tariff for his residential loads also or go with a seperate residential meter to get dwelling rate tariff.
 
mopowr steve said:
Maybe consideration on whether your customer wants to pay commercial rate tariff for his residential loads also or go with a seperate residential meter to get dwelling rate tariff.
Click to expand...
Business has been paying the bill, and likely to continue to pay the bill. Maybe not entirely kosher with IRS, but not likely to be caught either unless you are being investigated for tax fraud - then this is probably one of the smaller issues they may find out about.

Farmers around here do this all the time - maybe not so much transform from 480 to supply the house, but their farming is their business. They have one meter on the site that supplies farm operations as well as the house. The entire electric bill is likely written off as a farm expense in most cases I would guess. I don't do their accounting so I can't say for certain though.
 
Simply, yes, a residence may be supplied with three-phase. One of my customers lives in a large house with its own three-transformer-supplied service.
 
LarryFine said:
Simply, yes, a residence may be supplied with three-phase. One of my customers lives in a large house with its own three-transformer-supplied service.
Click to expand...

Get into those multi million dollar mansions, the load can possibly be enough that POCO won't want to supply it with single phase. Some items might be better off being three phase as well. Larger HVAC, elevators, some high end/commercial grade kitchen equipment...
 
I work in a lot of large custom homes, and they usually have 3/ph services. Not an issue with NEC. Occasionally we have to use transformers on equipment that won’t work on 208v.


Sent from my iPhone using Tapatalk
 
Status
Not open for further replies.
Top