Multiple Voltages to a single building

[cville1617]

The power company is allowed to provide multiple voltages to a single structure. In our case we have an existing 1000A single phase service. We are adding HVAC equipment that requires 3 phase 208V. Is there a reason that this additional voltage characteristic can not be added to serve this equipment? All distribution will be in the same electrical room and will be adjacent. Each will have code compliant means of disconnect.

 

[jumper]

In general, only one service to a structure/building unless you can meet the other requirements.

230.2 Number of Services. A building or other structure
served shall be supplied by only one service unless permitted
in 230.2(A) through (D).

 

[ceb58]

Most of the time they will not allow it unless you have need for diff. voltages. Say you have 120/240 and need 480 for equipment. Then they will allow it.

 

[cville1617]

This was my premise. We have 120/240 and need 208 to operate a large AC System that can not operate on 1P 240V. So this would meet the criteria

 

[pete m.]

According to 230.2(D) I believe it would be permitted.

Pete

 

[jumper]

NEC wise, maybe,

D) Different Characteristics. Additional services shall
be permitted for different voltages, frequencies, or phases,
or for different uses, such as for different rate schedules.

POCO may have a different opinion depending on who is paying.

 

[pete m.]

POCO may have a different opinion depending on who is paying.

This is true.. best to check with the POCO

Pete

 

[cville1617]

Thanks to all.

BTW - what does POCO stand for?

 

[jumper]

POwer COmpany.

 

[hurk27]

very common around here to see a single phaes service then a 200 amp 3-phase service, allowed all the time.

 

[cville1617]

Great help on this. Thanks to all. Our POCO allows this design and I felt like the code intended this application but always good to get those with bigger propellors to help.

 

[hillbilly1]

The POCO would probably love adding the three phase service, because they can charge more per KW! Around here if the service is single phase they charge residental power rates regardless if it is residental or commercial. I had to build a 1200 amp single phase service for a store because the owner wanted the cheaper single phase rate. He even converted his warehouse to single phase when the service burned up with old age.