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New shop building. 3 phase or single phase option?

EmGo

Diamond
Joined
Apr 14, 2018
Location
Over the River and Through the Woods
Just one piece of I hope helpful advice : don't talk to PG&E. Go somewhere else to investigate all the possibilities, choose what's best for you, then go to PG&E with your story.

Otherwise, if you approach them with something they don't like, they'll remember you later and ka-boom, there goes your updated plan. It's always easier if they haven't already said "no".

I'd actually avoid any talk of commercial service, that's always bend-over time. But 100 amps more for a house, that's common these days when we have electric ass scrubbers and breadcrust-removers. 100 amps will do you easy. You could probably get away with fifty if you had to (for the machines, not the whole package).

For that matter, you just want to replace all your old gas stove and kitchen appliances and hot water heater with modern efficient electric ones so you need an upgraded service, that should fly.

Fly low. Below the radar is best :)
 

BT Fabrication

Stainless
Joined
Nov 3, 2019
Location
Ontario Canada
keep the single phase, run rpc, 200A is plenty. my power co said i could do anything i wanted. like running single phase 600V to the house or anything up to 365A at any voltage, just had to pay for the wire and transformer.
 

Newman109

Diamond
Joined
Sep 4, 2006
Location
Sacramento County, California, USA California
I'm in Northern California and the local power service would quote around $50K for a new 3 phase installation. 30 years ago, they did it for free for my nearby professional machinist friend. I'd certainly go with an RPC, maybe a really good one like a Phase Perfect. I use a home-built RPC in my little home shop. Works for me.
 

amaranth

Aluminum
Joined
Apr 5, 2002
Location
Manchester, MI USA
Or tell them you're putting in a kitchen. A friend did a kitchen makeover with 2 ovens, freezer drawers, refrigerator, multiple cooktops, etc and had to get her service upgraded from 200 to 400 amps to cover it.

The utility had to put in a new feed and transformer and billed her around $3500 for that.
 

Pete Deal

Stainless
Joined
Apr 10, 2007
Location
Morgantown, WV
I’ve lusted for real three phase forever. I told this to a buddy who has real three phase. He said stay with single phase as long as possible. His monthly bills are way higher than mine, like 5 times , and i do a whole lot more in my shop than his.

Personally for those loads I’d just get an American rotary. It’ll run trouble free for years.
 

Gearclash

Aluminum
Joined
Feb 1, 2017
I put a 400 amp service in my shop and have a 30hp rotary phase convertor. 3 phase is not close and the power company said it would be a little of 100k to run 3 phase to my shop. I said thanks but no thanks.
What kind of conductors and panel(s) were used for your 400 amp service? I’ve only seen 400A 1ph service done once and in that install the electrician opted to use 2 parallel runs of 200A ea and 2 200A panels.

I will need to upgrade my shop electrical service at some point to handle a 40hp RPC.
 

Superbowl

Hot Rolled
Joined
Feb 12, 2020
I just upgraded my house to 400 amps. On the Power Company application I stated I was planning to put an addition on the house and add electric car charging. I did not say the addition was for a shop. We used two 200 amp panels. That allows for a smaller wires to feed the panels which are cheaper and easier to bend. 200 amp panels are cheap commodity items. I am sure any 400 amp single panel would be ridiculously expensive.
 

Superbowl

Hot Rolled
Joined
Feb 12, 2020
One tip. I chose to use new panels that took the same breakers I already had to save a few bucks.
 

ncjeeper

Cast Iron
Joined
Jan 20, 2015
Location
SW Virginia
What kind of conductors and panel(s) were used for your 400 amp service? I’ve only seen 400A 1ph service done once and in that install the electrician opted to use 2 parallel runs of 200A ea and 2 200A panels.

I will need to upgrade my shop electrical service at some point to handle a 40hp RPC.
400 amp box on the outside of the shop and we did 2 200 amp panels inside the shop. 60 foot long walls so I have one panel at one end and one panel at the other end.
 

Strostkovy

Titanium
Joined
Oct 29, 2017
Easy and cheap to build an RPC. But I suspect the powerco's nearby lines are at capacity. Where I used to live and work we were told some insane number ( I think $70k) to get 200 amp service and were laughed at when we asked about 3 phase.
 

Strostkovy

Titanium
Joined
Oct 29, 2017
I’ve lusted for real three phase forever. I told this to a buddy who has real three phase. He said stay with single phase as long as possible. His monthly bills are way higher than mine, like 5 times , and i do a whole lot more in my shop than his.

Personally for those loads I’d just get an American rotary. It’ll run trouble free for years.
When I switched to a 3 phase building it was such a relief. Going from a weak 100 amps single phase to 1200 amps of three phase. Power is more expensive because you can actually run your equipment.
 

david n

Diamond
Joined
Apr 13, 2007
Location
Pillager, MN
I’ve lusted for real three phase forever. I told this to a buddy who has real three phase. He said stay with single phase as long as possible. His monthly bills are way higher than mine, like 5 times , and i do a whole lot more in my shop than his.

Personally for those loads I’d just get an American rotary. It’ll run trouble free for years.
This all depends on the Power Co/CoOp and where you live.....................

My 3PH here was very reasonable..................$12K to run 1/8 mile down my drive. And part of that $12K was also for my house..........................
 

Pete Deal

Stainless
Joined
Apr 10, 2007
Location
Morgantown, WV
When I switched to a 3 phase building it was such a relief. Going from a weak 100 amps single phase to 1200 amps of three phase. Power is more expensive because you can actually run your equipment.
I can run everything I need to on my single phase. The op’s stated load would too. So this argument doesn’t apply here.

David N…. My post related to cost of operation not installation. You don’t mention your monthly cost operation vs monthly cost of a single phase service. I’m sure it’s probably another “it depends “. My point is/was that monthly cost difference can be very big.
 

drcoelho

Stainless
Joined
Feb 19, 2017
Location
Los Altos
I would pay the $50K and get 3-phase. Any issues and the utility will fix em. You still might need step transformers depending on your equipment, but they are inexpensive. Of course, this presumes you'll be in your shop over a long period to amortize the cost. But again, my view is that having utility supplied 3-phase is the way to go.
 

lucky7

Titanium
Joined
Sep 6, 2008
Location
Canada
Don’t think there’s a hard and fast rule. Situations, both individual shop, and utility specifics will vary and need consideration on their own merits. In my case, there’s no way to justify paying $50thou for 3ph. Or even $10thou. Make my own works just fine.
 
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Phil in Montana

Stainless
Joined
Jul 31, 2007
Location
Missoula Mt
Be carefull, just because you have a 200amp service DOES NOT MEAN THERE IS 200 amps there to use from the power co, there might be if your next door is not using 100 amps ect...Phil
 

Superbowl

Hot Rolled
Joined
Feb 12, 2020
If you have your own transformer serving just your house you will have the full 200 amps. If you share a transformer with neighbors then who knows.
 

Garwood

Diamond
Joined
Oct 10, 2009
Location
Oregon
If you have your own transformer serving just your house you will have the full 200 amps. If you share a transformer with neighbors then who knows.

Lol. Sure

I have a 45kva transformer for a 400 amp 240v single phase service. That's 187 amps. Not even half. And that's a bigger transformer than most get with a residential service.

With a 60hp rpc I can run 100 amps 3 phase continuous or 150 amps for about 30 seconds from that transformer.
 

Strostkovy

Titanium
Joined
Oct 29, 2017
Lol. Sure

I have a 45kva transformer for a 400 amp 240v single phase service. That's 187 amps. Not even half. And that's a bigger transformer than most get with a residential service.

With a 60hp rpc I can run 100 amps 3 phase continuous or 150 amps for about 30 seconds from that transformer.
In the US you are only supposed to use 80% of breaker capacity continuously, or 100% at reduced duty cycle (exceptions apply, I am sure). Which would be fine if you said 200 amps like I thought you did, but I just reread that you said 400 amps.
 








 
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