Let’s talk three phase...?

[Matt Mattingley]

Let’s talk three phase.?


As a residential consumer there is absolutely no reason to buy brand new three phase equipment in my opinion.

Looking through auctions and buying three phase equipment has its pluses....

You’re buying this from industry which consider these machines almost garbage.

Some of these machines are 230 V three-phase, 460 V three-phase, 550 V three phase, 600 V three-phase.

If you’re in residential and you only have 240 V single phase, don’t look at this gifted horse in the mouth!

Many machines can be converted using VFD’s, RPCs, PP’s(Phase Perfect) and static phase converter‘s .

Each conversion method has its pros and cons....

But, if you’re buying A surface grinder for $50 like I just did that is 550 V., that has three motors… What do you do?

[Warren Lake]

you simply cant compare the quality of single phase machines to so many great three phase machines older and even newer that are available. Whats the HP of the motors, old guy I bought machines from ran a stroke sander and combination machine off a simple roto for likely 30 years. 3 HP Roto 3 HP motors in the combo machine.

[Grant Wilkinson]

"As a residential consumer there is absolutely no reason to buy brand new three phase equipment in my opinion"

I respectfully disagree. I am a "residential consumer" and both my bowl lathe and my drill press are relatively new machines and both are 220 3-phase with single phase 220 to three phase 220 VFD's on them. The infinitely variable speed is much better than I was able to achieve in any other way and there were no wiring issues, since I had already wired 220 into my basement shop to handle my table saw, dust collector and jointer.

[Rod Sheridan]

[QUOTE=Matt Mattingley;2823307]Let’s talk three phase.?


As a residential consumer there is absolutely no reason to buy brand new three phase equipment in my opinion.

QUOTE]

I disagree Matt, I know people who have bought new 3 phase equipment for their home shop. A lot of new wood working machinery isn't available in single phase..........Rod.

[Rod Sheridan]

Jeff, Yes, 3 phase motor currents are lower than a single phase motor however their power consumption is approximately the same.

I have single phase high power factor, high efficiency motors that are more efficient than older 3 phase motors.

The single phase motor torque characteristics have nothing to do with how many "hot" leads there are, as most machine motors are 240 volts with 2 hot leads.

As to reversibility, single phase motors can be reversed by reversing 2 leads, either the start or run windings.

Regards, Rod.

[Matt Mattingley]

You know what, Rod......maybe I didn't type it well enough to explain it well enough to a guy like you, but my education is as an electrical engineer, and I understand how power systems work....quite well.


Jeff, your post seems to be missing.

[Jeff Heath]

Yep.....so am I. So long....

[David Kumm]

My take is that the word " absolutely " is too strong but the idea is valid. The economics of high end used equipment vs similarly priced new is pretty compelling. I'm not a bottom feeder and can afford any new machines I would want but I'd rather spend for other dumb stuff. A new three phase industrial sliding table saw is in the 15-20K range minimum. A used industrial machine is 5-8K and less if you shop well. My SAC 530 planer was 4K and like new. My T130 sliding shaper was 3750 and never used. etc, etc. I had to learn basics about electricity, bearings, and develop a relationship with a machinist but that is part of the fun for me. Edge and Disk sanders are way better and way cheaper used, but there are some new machines that have some benefits that make their higher price and lesser build appropriate.

Beyond that, three phase is now available to anyone for less than the cost savings available if you are willing to learn the used market. I have VFDs, RPCs, and several Phase Perfects. All have their place and none are deal breakers from a cost standpoint. I also have transformers for 275v, 480, and 600v. None are that complicated to figure out if it turns out the motors can't be rewound. Even factoring in the cost of the electricity conversion, used equipment comes in much cheaper than new. For a hobby guy, new high end three phase equipment is a choice similar to buying a new Mercedes S550 instead of a two year old one with 1500 miles at a 40K discount. ( It still depreciates really fast ). Dave

[David Kumm]

Jeff, since I'm not allowed to see the post, I don't know the circumstances but don't leave. Diversity of opinion is good and people who know both woodworking methods and understand the machines that accomplish the task are rare. Dave

[Matt Day]

Jeff, there are some very sensitive people on this forum, too sensitive in my opinion. But I don’t make the rules so I have to abide by them just like you do.

Taking your ball am leaving seems a bit immature, no offense intended. Please stick around and continue to contribute to our discussions.

[Warren Lake]

Jeff Rod is one of he nicest people on the planet. There are 2000 plus people in my phone book im a fairly good judge from knowing so many. Ive been very lucky. Rods been here before the only thing I dont like about him is he is so smart. Im joking as I do like that, its just that im not and have a different brain, he also doesnt present himself that way which is nice.

Those were just the words he used, hes the last guy meaning to offend someone. Now me Im good at it, id claim I learned it from Martin but people would know its already been there. (you can call my sister she will verify)

Anyway Rod meant no offense. The bit I know him its instant where his heart is. When you ask someone to help you and you ask what they want to do that and they say a tea you clearly realize you are talking to a certain type of person.

[Mike Kreinhop]

Let’s talk three phase.?


As a residential consumer there is absolutely no reason to buy brand new three phase equipment in my opinion.


I am a residential consumer and buy three-phase equipment whenever I can. My house, as well as most houses in Germany, are wired with 230/400 three-phase service. :p

[Mark Hennebury]

[QUOTE=Mike Kreinhop;2823519]I am a residential consumer and buy three-phase equipment whenever I can. My house, as well as most houses in Germany, are wired with 230/400 three-phase service. :p

You are Lucky; If you had 600 volts as well I would move to Germany.

[Mike Heidrick]

I really hope zero people around me disagree with Matt.

If you bought higher voltage equip and three phase, you will need a transformer and rpc.

[John C Cox]

I agree that often as not - "normal" residential electricians never see a need to install 3 phase power into dwellings.... 99% of people would never use it for anything....

Often as not - you can get 3 phase 208 in many residential and light commercial areas. That's simply 3 phase where each leg is regular 120v... 220 is similar - except that it is 2 phase with 120 on each leg....

if you can get 208 3 phase easily enough - all you need is an appropriate step up transformer and off you go... These can be bought used cheap...

I personally would not buy equipment that requires anything higher than 480 3 phase... Above that - you start pushing up into "Medium voltage" stuff and electricity behaves differently. You have to be VERY careful about wire terminations as well as keeping breakers properly maintained. This is the realm of paying electricians - not doing it yourself.. You can kill yourself in a hurry...

Even then - you will likely have to find an electician who has the correct credentials/qualifications/training and equipment to work on a system above 480v... Most simply do not.....

[Warren Lake]

Mark Ill get you a transformer for christmas, rather you stay here though.

[Mark Hennebury]

Mark Ill get you a transformer for christmas, rather you stay here though.

https://sawmillcreek.org/showthread.php?265774-Let’s-talk-three-phase&goto

thanks Warren, I will stick around for a while. I have 240/480/600 so i am good.

[Brian Holcombe]

I wouldn’t necessarily order a new machine in three phase, but once I did a bit of research and spoke to people such as Mark Hennebury (thanks Mark!), I found that three phase conversion was pretty easy to do and opened up a broader range of equipment choices.

One thing, however, had I prepared a little sooner I could have gone for a three phase jointer/planer in the same model FS41 Elite S which features a motor to raise and lower the table with a DRO. So there are some options manufacturers provide to three phase machines that they do not otherwise provide.

[Alex Zeller]

It's too bad that getting 3 phase power ran to a house is so expensive. I'm always watching industrial equipment auctions. Older equipment seams to go real cheap. If I had my way I would be buying a lot more than I do. I would be in worse shape if I didn't live in the north east. I'm far enough away from a lot of what I really want to allow me to think twice.

[James Zhu]

It's too bad that getting 3 phase power ran to a house is so expensive. I'm always watching industrial equipment auctions. Older equipment seams to go real cheap. If I had my way I would be buying a lot more than I do. I would be in worse shape if I didn't live in the north east. I'm far enough away from a lot of what I really want to allow me to think twice.

It is very easy to get 3 phase power from single phase. You can use either a rotary phase converter or digital phase converter (Phase Perfect).

[Phillip Gregory]

I agree that often as not - "normal" residential electricians never see a need to install 3 phase power into dwellings.... 99% of people would never use it for anything....

Often as not - you can get 3 phase 208 in many residential and light commercial areas. That's simply 3 phase where each leg is regular 120v... 220 is similar - except that it is 2 phase with 120 on each leg....

if you can get 208 3 phase easily enough - all you need is an appropriate step up transformer and off you go... These can be bought used cheap...

I personally would not buy equipment that requires anything higher than 480 3 phase... Above that - you start pushing up into "Medium voltage" stuff and electricity behaves differently. You have to be VERY careful about wire terminations as well as keeping breakers properly maintained. This is the realm of paying electricians - not doing it yourself.. You can kill yourself in a hurry...

Even then - you will likely have to find an electician who has the correct credentials/qualifications/training and equipment to work on a system above 480v... Most simply do not.....

120/208Y service is typically seen in "residential" settings only in heavily built-up areas, such as a large apartment building. You do not generally see it in freestanding dwellings as each of those typically has its own transformer which is essentially always 120/240 split-phase. My house is about 4 miles away from the nearest utility 3 phase pole, they simply ran one phase up my road and that's all there is. That has been the case pretty much everywhere I have lived, and in one case there wasn't a 3 phase pole for about 15 miles. Most power companies will not run 3 phase to a dwelling. In some cases you can get them to run it to a shop building, *if* you are close to a 3 phase utility pole, *if* they wish to provide you with it, and *if* you are willing to pay a lot of money both initially and on an ongoing basis for the service. Most smaller shops that can get 3 phase service get 240 center-tapped delta so they can run 240 volt 3 phase loads, 240 volt single phase loads, and 120 volt single phase loads. 120/208 is typically seen in commercial establishments as most loads are 120 volts except for outdoor lighting and HVAC being 208 3-phase. Large apartment buildings may have 120208, typically stepped down from 277/480 from the POCO as they use 480 for elevators, fire control, and HVAC and have their own onsite transformers to step down to 120/208 for use by the individual units (208 single phase being used by stoves and dryers, 120 volts for all else.)

Most of Canada as well as some sporadic places in the Northeast and Southeast use 600 volt (aka 550 or 575 volt) 3 phase. It's treated exactly like 480 3 phase is. Medium voltage does not start until 1000 volts and yes, the rules for that are vastly different than for <1000 volts.

[Martin Wasner]

As long as you have the amperage. Any little motor you're going to get in single phase and be able to run out of a residential panel, just put a vfd on it and move on.

Tough to find small to medium, (10-50hp), sized motors in single phase though. Heck, you have to sell an organ just to pay for the wire for a 200 amp, 208v circuit for 50hp.

[Darcy Warner]

May have to sell two if you have to buy a new breaker and fused disconnect. Lol

[Tom Trees]

Thought I'd mention that I visually checked the consumption of my machine the other day....
Looking at the wheel spinning on the meter, while my 24" ACM bandsaw was running with a 1" blade on it.
It has a three phase dual voltage, 3hp motor.
I was quite pleasantly surprised at how efficient it was, drawing little more than an old laptop.

[Matt Mattingley]

As a residential consumer there is absolutely no reason to buy brand new three phase equipment in my opinion.

Yes, I am quoting myself. Maybe I should’ve put “hobbyist” after residential. (One man shops, not relying on shop income for livelihood.)

I think the biggest single phase motor I’ve ever seen on a machine was 10 hp requiring 60A Circuit.

One thing I have commonly seen, as soon as machines start using multiple motors for one common process, they are usually three phase.

Most of my stationary equipment is three-phase. They were bought from industry, at about 10% or less of its new replacements value.

Yeah the good old machines are big and heavy, but not much wears out. My oldest machine (I think) is 1942. It is a Do-All bandsaw 3-phase. I guarantee it will still be around in 50 years. Why...because it can weld its own blades and it was built right 76 years ago. It does weigh in just over 1000 pounds. It cost me $750. It is 230 V three-phase. I’m pretty sure it’s comparable new will be 10 times the price, and it will not be around in 50 years from now.

[Lee Schierer]

My understanding is that three phase power is used for industrial applications to balance the electrical load. If large industrial shops with lots of machines used single phase power they could cause unbalanced loads on the electrical grid. They would have to pay attention to which phase they connected new equipment to during installation and when running various machines throughout their facility. Using three phase eliminates those problems. They can start and stop any machine at anytime without concern about balanced load.

[Mark Hennebury]

I had at the start had 3 phase in my shops as they were commercial buildings. in 1991, i moved into a small commercial building in an industrial park that did not have three phase, after getting a $30,000 quote for running the powerline 100ft from the pole to the building i purchased a used roto phase and have used i ever since.I have 240 volts, and transformers for 480 and 600 and the largest motor that i use is 7.5hp the total allowed running at once is 21hp if i recall. Never had any problems. the only downside of the rotophase is the loud hum i makes, but i play music all day anyway so it doesn't really concern me.

PS. Brian, you are welcome.

[Martin Wasner]

Mark, a lot of what figures into the cost of bringing in another service, is how much you'll use it. I had to trench in about 1200' to bring the service into the new shop. I think it ended up costing me $3500. But, I've got about a $1k electric bill each month.

[Mike Heidrick]

A lot of what figures into the cost is how much work you do yourself.

[Martin Wasner]

A lot of what figures into the cost is how much work you do yourself.

I couldn't do any of it myself. As in zero. I ran the feeds out to the transformer, but everything between the transformer and the pole was off limits.

[Ken Combs]

Sometimes I forget how lucky I was. Our local power company is our city utilities dept. they buy wholesale power and resell through the city distribution network. I inherited a building built in the mid '60s and shortly thereafter the main breaker failed. It had never been switched off or tripped to my knowledge since installed. It just quit, opened no juice!
I had purchased some used Square D 3 phase breakers and panel at auction just because they were dirt cheap. And, had a 3 phase belt/disk sander from the same auction. And, needed to upgrade my air compressor.
So, off to talk to the city utility guys. Now, this is a semi-commercial building with its' own service 300 feet back of my house. They allowed me to pull a permit, install my breaker box and wire to the weatherhead, and call for inspection. They installed an additional transformer and one more conductor from the street to my pole. I have 240 high leg delta 3 phase which provided 120v and 240v single phase also.

Best part: total charge to me? zero. Foreman was a woodworker, had a used transformer available and an idle crew and wanted to be helpful

[Andrew Hughes]

My first Rpc was loud new and just kept getting louder.I finally sold it after it started vibrating the wall it was sitting next to.
I think it was made in someone’s garage. It was cheap so I got what I paid for.
I bought a Kay Phasemaster And have it loacatedbin same spot as the other. I swear I cannot hear it running and it not because I’m getting old and losing my hearing.:rolleyes:
Since my three phase journey has began my electrical service has gone thru some nice changes. A new 200 amp panel with a 4/o service drop.And a 27kw transformer.I share half with three neighbors.
Before all this I had a soft service and lots of light dimming.
I’m a amateur woodworker obviously ;)

[Mike Heidrick]

Exactly Martin. I know you could have done it yourself cheaper.