Newbie 3 phase question

[shananigans]

Anyone who could give me some direction on tackling this problem would be grwatly appreciated.

I'm a small business owner contemplating moving our fabrication shop out to a barn on the outskirts of town. The barn is right near the street and overhead 3phase lines (presumably 3 phase since there are other newer industrial buildings on the same street.) There is also a farmhouse right on the street with its own overhead 1 phase drop coming from it's own pole mounted transformer...doesn't look like any other draws are on this transformer.

Our fabrication equipment currently draws 30-35 hp. A lot of this...about 20HP is from a 3phase motor running a large vaccum system.

My question is how to go about getting adeqaute 3 phase power to the barn. It's one of those "is it worth it" type questions. The barn is about 75' from the base of the nearest pole (the one with the transformer feeding the house).

The barn is located on the Central Coast of California and local power is supplied by PG&E.

Any direction in how to approach this project would be great...especially any guesses at how much it might cost! I've also considered using a rotary phase converter, but it seems silly when 3 phase is so close by.

Thanks in advance for your help!
Shannon

 

[weh3]

A rotary phase converter is simply a single-phase motor driving a three-phase generator. You don't gain anything with that, and it still has to be as big. Static phase converters are available. Good luck getting three-phase to the barn for a unless you want to pay the capital cost.

William

 

[dpc]

Unless you want to put in a a generator or some type of phase converter, you will have to get it from PG&E. I would first call PG&E and tell them your plans and that you need a three-phase service. Since this is a commercial account, they should be willing to provide three-phase power without much argument - the only question will be how much they will charge. If the price seems too high, you can ask of a copy of their tariffs and rate schedules to make sure they are applying their rules appropriately. If you're still unhappy, you can bring it up with the Cal. PUC.

No point in worrying until you get a price from PG&E. They'll be happy to talk with you - they do this for a living.

 

[jraef]

If 3 phase is already on the street, PG&E will be able to offer it to you at a reasonable cost if you are (or are going to be) truly an industrial or commercial customer. The cost of running that to you will depend on your expected kWH usage, and is often amoritized over a period of time IF your property is zoned as commercial / industrial. If it remains zoned as aggricultural or residential, they may make you pay all the costs up front because the next tennant may not use or want the 3 phase service.

They actually would prefer you to be a 3 phase service (again IF it is already on that street) because load balancing is better that way for them. Where they really sting people is when yu want 3 phase brought in to your garage for 1 or 2 machines that are for hobby work and will only run occasionally. That isn't worth it to them.

"Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more."
Nikola Tesla

 

[EEJaime]

Contact the PG&E commercial Service Planner for the area. He will at no charge to you look at the site conditions. I would imagine that if you are only 75 feet from the existing pole, they will install two additonal pole mounted transformers to provide your service. If your loads are at 208V/3ph or 240V/3ph the costs should not be prohibitive. PG&E is required by PUC to serve commercial customers at commonly available voltages and this sounds like a very typical installation. You will need to provide a service panel with a meter socket and a properly supported rigid conduit mast with a weatherhead or their incomming overhead conductors. PG&E has published service requirements in their "Greenbook". Look at

http://www.pge.com/docs/pdfs/custom...ervices/greenbook/service_requirements/06.pdf

You will find all the info you need. You can get any associated fees from the service planner. The cost for a 200A, 120/208V/3ph/4w.service is shown in the RS Means estimating book System D5010 120 0220 (which includes a service entrance cap, service installation, breakers, metering, 20'of conduit and wire), as:

$1225 for material, $1400.00 installation, for a total of $2625.00. Means tends to be somewhat conservative, and this is a typical installation, yours will have other factors, but that will put you in the ballpark.