Should I install 3 phase?

Brian Altop

Member
Messages
274
Location
Tacoma, WA
After almost 10 years working for someone else I am going into bus. for myself after being laid off. Right now I am finishing up my shop, changing it into a production shop. I will be purchasing a shaper and a new table saw (saw stop). I have the option then of choosing 3phase machines and it is an option to have 3phase installed. I was told by the Elec. Comp. that they just had to drop a line to the house. (haven't heard back on the cost of that yet).

I understand the theory behind the 3phase, just wondering if it was truly worth it and if there was truly that much of a diff in performance.

I will be doing custom floors, cabinets, trim, and other specialty projects including furniture. Probably making my own flooring for individual rooms/hallways and milling my own lumber for cabinets will be the biggest 'production' task I will be putting through the machines. I'm sure the standard 1phase 220 machine will handle it just fine.

Also, since there are only 2 or 3 machines that I'm going to upgrade that have the option of 3 phase would it be worth it?(table saw, shaper, planer):dunno:

Just curious if it was worth looking into.

Thanks,

Brian
 
I think it will depend on how much production you're planning to turn out and will there be on-going increased costs?

When my in-laws upgraded the ice company there was a huge difference, but the electric company was going to charge them around $22k for the upgrade. A friend of my FIL had worked for the electric company as engineer. He told them that basically they needed to show how much additional electricity they were going to use to show it was to the electric companies benefit to install the line for free, which in the end they did.
 
when i built my shop i too was gonna look into it and did,, i was gonna need new service anyway,, it was gonna cost me an additional $68 a month over the regular kw cost of use..i opted out of it and if yu run across a good 3 phase machine way cheaper than a single phase one yu can get transformers and have the best of both world cheaper..
 
For the size shop your talking about I would say pass on the 3 phase.
1 as Larry said you can get a phase converter Or make one that will run the machines just fine.
2 resale of the equipment is going to be higher if it's single phase.
 
I would only look at getting 3 phase, if you are planning on getting some larger equipment and hiring on more help. My current shop as no 3 phase within 10 mile of it. So this summer when we upgrade the power we are stuck useing a very large phase coverter which will supply all the 3 phase. My main reason for doing it is simple. I make alot of molding and flooring and all that type of equipment needs 3 phase or just hope the farm next door doesnt start the milkers while your starting up the molders.:D
 
across a good 3 phase machine way cheaper than a single phase one yu can get transformers and have the best of both world cheaper..

Sorry Larry, but unless 3 phase converters are way cheaper there in US than here it will not work, besides apart from the third phase one has to take into account the amperage needed. Unless I understood your comment the other way around.

I've been thinking about using a converter I have to only run a 3 phase blower to make a cyclonic dust collector and I gave up on it.

My next move (some day) will be get three phase current and power both the shop and my home with it. The home wil run single phase and the shop machines 3 phase, that can be done but the other way around is waaaay to difficult and expensive.
 
Toni, a 20 HP converter is around$ 2500 plus wireing and subpanel. In total if you do most of it yourself your looking at about $4,000.
 
My shop has six 5 hp motors, and will probably go to 7. Yes, single phase works fine. But IMHO 5 hp is about the limit you should consider for single phase. I don't recall ever seeing a 10 hp or larger single phase motor.

The big deal in my mind is how often you stop/start the motors. Some vendors recommend no more than 3 times per hour with a 3-5 hp motor, others say no more than 6 times per hours. The starting current is higher longer on single phase, so you are building heat in the motors each time you start them.

When you go to three phase, some power companies put you on commercial service. The cost per KWH drops (sometimes as much as to half price) but you start to pay a demand charge, based on the peak load you put on the power system in the last few months. If you can manager your demand (wait a few seconds between turning motors on, be sure your AC/Fan/Compressor doesn't kick on the same instant you start something else) then the demand cost can be small, and the commercial power rate can be a net savings. But if you have occasional spikes in use, even for a few seconds, you will be punished. Be sure you have magnetic starters so everything doesn't come on at the same time following a power blip.
 
As always guys, thanks for all the input. I will be calling the power company tomorrow to find out what the cost diff is going to be and exactly what the charges will be. I will post an update with prices FYI and curiosity. This is for the city of Tacoma at a residence (I've got a 550sf shop behind the house).

I'll keep you updated.

Thanks!

Brian
 
I have no hope of ever having 3 ph at my new shop. I have a 50hp RotoPhase converter I bought new some time ago in preperation for this day. I paid $2600 for it. It requires 100 amp at startup, and will of course run a total of 50 hp.

That being said, if I had to do it over again I would, and still may, buy a Phase Perfect converter. Better power that is clean, cleaner than the power comeing in, and is good for all size motors, something that rotarys are not great at, and it makes very little noise. Turn it on in the morning and forget it. Seems like a 20 hp unit was around 3K, but don't quote me. I know the one I wanted was $4600, but it was larger.

How much you give me for my 50 hp?;)
 
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