Shop power question - who needs 3 phase anyway?

[lou sansone]

Good morning wood workers

I wanted to take a poll about shop power. As you have seen I am selling my laguna lt 24 band saw ( fair amount of interest ), but I have found that I could have sold it 5 times if it was single phase. The Laguna saw I have is a 3 phase model. I told my wife about it and said that I was suppriesd that more folks did not have 3 phase in their shops. She looked at me with that look that said "lou, only nuts like you have 3 phase" now she didn't actually say anything, but gave me that look. Maybe she really meant some other thing, but you guys know what I mean.

So here is the problem. Am I the only nut out there with 3 phase equipemnt or a 3 phase shop. Would most folks NOT want 3 phase if it was available to them. I need help here!!

here are the poll questions

1. I have 3 phase or 3 phase equipemnt
2. I wish I had 3 phase
3. I don't have any
4. Don't have any and don't want it


thanks
lou

[Ken Fitzgerald]

Lou....first off...most of us drool as you slowly and I mean slowly expose your shop to us......Most of us don't have 3 phase readily or economically available. Myself...it's not readily available.

[Tyler Howell]

Would if I could! In my next life.:o

[Maurice Ungaro]

Lou,

I don't have it, and couldn't justify the cost of getting it and the 3-phase equipment to go with it for my "hobbyist" shop. You, on the other hand....kinda deserve to have it.

Maurice

[Bruce Page]

Lou, I have two 3ph machines but don't have 3ph power, I run them both off of a static converter. I guess if the utility company had 3ph at my door step I might sign up for it, but it wouldn't be a high priority for me.

[Wes Newman]

If they offered it I'd take it in a heartbeat. Lots of machinery for sale is 3-phase and that kind of puts the big kabosh on buying it.:(

[Mark Singer]

For the small furniture and cabinets I build, I haven't found I need it. The machines I have seem to run fine on single phase. I have a friend that builds custom doors and windows and loves the old iron...he has 3 phase and really likes the older machines. Another down the road has a phase converter for an older jointer he has....I don't really miss it...maybe if I had it I would really feel I needed it all along....

[Jeff Sudmeier]

I think there should be another option in the poll, I don't have it but would sign up if it were available. I selected I wish I had it, but it is not a HUGE deal to me. If it were offered I would probably use it.

[Byron Trantham]

In my wildest fantasies about equipment I might want, I haven't come up with anything that would require 3 phase.

[Lynn Kasdorf]

I'd love to have a 3 phase panel in my shop. And I may yet. However, even though it is on a power line cutting right across our property (grrr), I've been told that it would be quite pricey to get a drop to the barn. It is most annoying- there it is, uglifying my property, but I can't get to it.

However, I need to actually talk turkey with our power company. I get the impression that there are no hard and fast rules on the cost- you need to make a good case.

I just acquired a lovely SCMI sliding table saw. I need to power it somehow and I've been weighing my options. It came with a nice 5hp 3ph motor. I have a coupe 5 hp single phase motors, but these weigh about 25% more that the 3phase of the same power.

I could buy a VFD for about $300-$500 that will handle 5hp, and this is a great option. I could make a rotary convertor out of an unwanted 3ph motor. I could make a static convertor, althought this gives about 2/3 the rated power of the motor and is not great for a motor undergoing varying loads.

Or--I could just get actual 3ph power into the barn. Gotta look into that.

I also have a 3phase jointer and pedestal grinder. And I imagine I'll come across a bigger metal lathe one day that will certainly be 3 phase, so having it in the barn woudl be really great, but the initial hookup fee and the monthly fee for the meter could be prohibitive. They charge me $10/month just for the single phase meter that is there now!

[Frank Pellow]

I just recently started to use 220-240 volt (single phase) machines and they are a great improvement over 110-120 volts. :) But, I doubt very much that I will ever have the demand for 3 phase for my small hobiest shop.

[Todd Burch]

I put 3ph power in last year in preparation for the new equipment I purchased that required it.

My going to 3ph wasn't so much a desire for 3ph, but a means to an end - I needed bigger, more powerful equipment than what could be had in single phase.

I purchased a used 10HP rotary phase converter, and it works great, but it would be so nice to not have the noise or the hassle of always having to turn on three pieces of equipment instead of two (converter, dust collector, machine).

Plus, there's no 3ph like utility company 3ph. Wish I had that. I will in the next shop - scheduled for about 5 years away.

Todd

[Bill Lewis]

The only advantage to having 3ph power for a hobbiest shop is that (used) 3 ph equipment is cheaper to buy. Well it is more efficient too.

A co-worker's father had the opprotunity to run 3 ph power to his (home/farm) shop druing construction. Apparently it would have only cost him a couple of hundred more to do so at the time. They didn't think they needed it, and now are sorry they didn't. He picked up a 3ph mill really cheap, and now have to come up with a converter.

BTW, Lynn, If I'm not mistaken, you still only get 2/3 power with a rotory contverter too.

I used to know someone who built a rotory converter using an old 3ph motor. To use it, he had to wind a cord on a pulley, turn it on, then pull the cord to get the (converter) motor going, then turn on the machine (14" radial arm saw). What a trip!

[lou sansone]

I'd love to have a 3 phase panel in my shop. And I may yet. However, even though it is on a power line cutting right across our property (grrr), I've been told that it would be quite pricey to get a drop to the barn. It is most annoying- there it is, uglifying my property, but I can't get to it.

However, I need to actually talk turkey with our power company. I get the impression that there are no hard and fast rules on the cost- you need to make a good case.

I just acquired a lovely SCMI sliding table saw. I need to power it somehow and I've been weighing my options. It came with a nice 5hp 3ph motor. I have a coupe 5 hp single phase motors, but these weigh about 25% more that the 3phase of the same power.

I could buy a VFD for about $300-$500 that will handle 5hp, and this is a great option. I could make a rotary convertor out of an unwanted 3ph motor. I could make a static convertor, althought this gives about 2/3 the rated power of the motor and is not great for a motor undergoing varying loads.

Or--I could just get actual 3ph power into the barn. Gotta look into that.

I also have a 3phase jointer and pedestal grinder. And I imagine I'll come across a bigger metal lathe one day that will certainly be 3 phase, so having it in the barn woudl be really great, but the initial hookup fee and the monthly fee for the meter could be prohibitive. They charge me $10/month just for the single phase meter that is there now!


Dear lynn and others

Lots of good comments from all of you. Here are a couple of thoughts and potentially some clarification.

1. I am not lobbying for folks to "convert" to 3 phase. I just wondered about the demographics of the Creek and what the mindset was in regard to this question.

2. I do have a seperate shop with 3 phase. When costing out the whole job, I went through a number of possible configurations with the power company. To my recollection there was no "big cost" difference either way. The only thing you really pay for is the wire and the hook up. They don't charge for transformers or anything else. My service is an underground service and the requirements are the same if it is single phase or 3 phase. The load center and meter socket are a little more, but not by about 200 dollars.

3. From what I can tell by comparing my home bill and kwh usage and my shops kwh usage ... the cost per kwh is essentially the same ( just take the total kwh and divide it by the bill... the misc charges and recovery fee for who knows what just gets thrown into the mix.)

4. Lynn is right about making a case for the Power company. All I had to do is make a list of the motors that I would someday have and that was enough! So just make that list and they should be happy. make sure to include a 20 hp motor for your wide belt sander that you will drag into that big barn!!!

lou

[markus shaffer]

I have 3 phase power supplied to me. But then again, almost every building in Manhattan has it from what I understand. At least most newish buildings.. We'll see how things go if I ever move out of this shop being that I've got three machines here that run on it.. That might prove to be a problem.

-Markus

[Mike Elo]

I could see it for a commercial shop with large motors that are in continuouse use.
If used 3 phase equipment is cheaper it's because there is no demand for it.
I just don't see any other advantage. Am I missing something? Do the people who want 3 phase all have commercial shops? Mike.

[Bob Nieman]

I actually have three phase to my house, but not to my shop, which is in a detached garage. The three phase is for my air conditioner. the electrician suggested that I have it because early AC units were three phase and the owners of the house were early adopters (and live in the center of town). Can't say I have any intention of wiring the garage with it though. My shop is way too small for industrial equipment. I have a 220 line, but I realized that the electrician used half for the 110 circuit, so it isn't dedicated 220. (which I want for a DC)

[lou sansone]

I could see it for a commercial shop with large motors that are in continuouse use.
If used 3 phase equipment is cheaper it's because there is no demand for it.
I just don't see any other advantage. Am I missing something? Do the people who want 3 phase all have commercial shops? Mike.

Good question mike and I think that you have answered it in a way. Three phase helps in lowering the single line amperage load to a motor. Take for example a 10 hp single phase motor and a 10 hp 3 phase motor.

the 10 hp single phase motor = 44 amps @ 230 and about $750
the 10 hp 3 phase motor = 23 amps @ 230 and about $400

There is a big difference also in the motor control contactors as well with the higher amperage draw in the single phase case. All in all the 3 phase motors really have a total overall cost.

The problem becomes real accute once you go over the 10 hp range. It is very hard to find any single phase motor above the 10 hp range.

For a wood worker the worse offender is the wide belt sander. It is not unusuall for them to have at a minimum 20 hp motors and many have 30 or more. There is just no way to run them with single phase motors.

I think for the serious hobbiest that single phase is really the right choice, unless they are nuts like me! Like I said in the beginning of the post, I just wanted to provide some fodder for discussion and to see where folks are comming from.

thanks for your response
lou

[Frank Bertrand]

Lou, I have 3 phase. I'm even more interested in your saw now ;)

[Steve Stube]

At the time I built my shop 3 ph underground and a transformer mounted outside my shop was < $800. plus a monthly commercial minimum charge. I came close to having it installed but couldn't quite justify the monthly charge as I wasn't using that much power on rotary converters. That monthly charge is nearly 4X greater now and I'm downsizing (no more big motors) which makes me glad I didn't get the 3 ph in the first place. Another factor that has completely eliminated the need for power company 3 ph (for my operation at least - one man hobby shop) was the adoption of VFD's. I smile and pat myself on the back every time I think about avoiding the noisy transformer and extra monthly bill.

[Dennis Peacock]

I wouldn't mind having 3ph power at my shop....but the last time I checked, I would have to pay them $35K to run it to my house for about 1 mile of power line, purchase all my own powerline poles, purchase the transformer and then change out my panel, meter base and power connection over to 3ph. For me, single phase is fine.

[lou sansone]

I wouldn't mind having 3ph power at my shop....but the last time I checked, I would have to pay them $35K to run it to my house for about 1 mile of power line, purchase all my own powerline poles, purchase the transformer and then change out my panel, meter base and power connection over to 3ph. For me, single phase is fine.

dear dennis

Wow that is a lot of money. The big problem with 3 phase is getting it. Once you have it at your shop then it is great. I wouldn't spend the 35 k either.

lou

[Rob Russell]

3-phase for me means a rotary pase converter. The new machies I bought are 3-phase because that's what they use once you hit 7.5HP.

[Richard Wolf]

I have 3 phase in my shop but do not use it. I just don't like buying equipment that will have a very limited market when I want to down size or upgrade or move or retire or my family to sell when I'm gone. I am a two man shop and never could justify needing a machine that was so powerful it only was avaible in 3 phase.

Richard

[Alan Turner]

I like old iron, and tried to get 3 ph. to my home basement shop. The utility would not even have a serious discussion about it. But, in the new industrial building that myself and a couple of friends acquired, there is 3 phase and 2 phase (which is a bit local to the Philadelphia market, I think). There are several motors in the shop that are 2 phase, such as the overhead steel door, and the conveyor belt motor.

With 3 phase, I am in the process of tooling up the new shop, and except for a saw stop, will probably go with 3 phase equip. I think that any large jointer is a direct motor drive 3 phase, and the DMD makes it hard to change out the motor.

I actually have acquired title to a couple of larger pieces, but have not yet picked them up. More to come, when I can post a pix or two.

[John Renzetti]

Hi Lou, I have three phase power via two Kay Phasemasters. There are 6 machines in the shop that are three phase. Once the phaseconverters are set up it's really no big deal.
take care,
John

[Charlie Plesums]

If I'm not mistaken, you still only get 2/3 power with a rotory contverter too.


Pull out the old electrical engineering cobwebs...

Three phase power in a motor gives much smoother power, including substantial starting torque, without the tricks required to start a single phase motor. With smaller motors, no big deal. With bigger motors, it is a big deal, which is why industrial areas have it for the larger motors. Most residential areas only have single phase (1/3 of the 3 phases that are generated and run on the transmission lines), so the power company gets cranky if you want them to do the rest of the wiring in residential areas.

A static converter only provides single phase, but applied to the motor in a way that provides .707 power (70%).

A rotary converter actually uses a single phase motor to power a 3 phase generator, so you get real 3 phase power. The electric bill increases by the cost of the electricity to make the noise and heat of the converter - as little as 1-2% with high efficiency units. But the motors powered by the rotary converter run at full efficiency.

Hope I remembered the EE classes right!

[Paul B. Cresti]

Made the switch back in April 04. Sold all of my single phase machines and now am in three phase. All but two of my machines are three phase now and that may soon be all but one. My three phase is brought in via a 15hp Kay rotary phase converter, very quite and efficient.

[lou sansone]

I like old iron, and tried to get 3 ph. to my home basement shop. The utility would not even have a serious discussion about it. But, in the new industrial building that myself and a couple of friends acquired, there is 3 phase and 2 phase (which is a bit local to the Philadelphia market, I think). There are several motors in the shop that are 2 phase, such as the overhead steel door, and the conveyor belt motor.

With 3 phase, I am in the process of tooling up the new shop, and except for a saw stop, will probably go with 3 phase equip. I think that any large jointer is a direct motor drive 3 phase, and the DMD makes it hard to change out the motor.

I actually have acquired title to a couple of larger pieces, but have not yet picked them up. More to come, when I can post a pix or two.

hi alan

good points. When might we expect you to post those old iron photos?

Your holding out on us!

lou

[lou sansone]

For those who are using static converters, how do you like them and do you really notice a big difference ?

[lou sansone]

this is the last day to cast your vote on the shop power question.

lou

[lou sansone]

Well the votes are in on this question. The results are a little suprising, in that I would have thought that far fewer folks would have wanted or had 3 phase in their shops. Thank you for all that participated in this poll.


kind regards
lou