Phase convertors?

[Kurt Wyberanec]

Hi all, as some of you know and a boat that many of you are probably in, in looking at a new saw and wondering if a phase convertor is worth it for me.

Most of you have suggested phase perfect, a digital static convertor vs a rotary model for a number of reasons and with even the little bit I know about them it makes sense to me.

Of course this does bring into account a substantial cost even if used (though I haven't seen much used) so there is a trade of but it opens other possibilities. In my case I might also have to revamp my electric because it might be a bit undersized but going to look into that.

My question is aside from phase perfect are there any others you might recommend? Searching a bit I found the place below that sells digital static models at a ridiculously low price and I can't understand the price disparity... they mention if you need different hp than what it listed to just contact them. The largest they list is only 3hp and I probably want 7.5-10 but their 3hp is only $89!!! That's only about 25x less than a 7.5 pp.... what gives? I know a lot of people say you get what you pay for and generally that's usually true but definitely not always the case and it leaves me thinking but this is a huge price gap.... maybe I'm missing something and maybe there his hidden cost...I might call for a 10hp unit they might say 3k who knows.

So long story short, take a look at this let me know what you think and let me know there are any other good quality lower cost alternatives to pp...I don't think I want to go rotary because it will increase my bill significantly and almost definitely increase a lot to the install since I will definitely have to upgrade the panel.

Am going to put a call into pp for additional info.

Thanks in advance!

[Charles Coolidge]

What 3 phase machines do you plan to run?

[Andrew Hughes]

I have a Kay phase master. It’s so quite I leave running more then I should. As far as cost running or idling it doesn’t draw anything worth mentioning idling. Running it’s just a third 120 v leg.
What I learned from installing a 3ph system. Installing a bigger panel with more circuits doesn’t necessarily mean my service is upgraded.
How close I am to the transformer and the size of the line drop wire play a part.
Good Luck

[Jared Sankovich]

The phase perfect isn't a static converter. The $89 version (and they all basically) are just a start capacitor. The motor only runs on 2 phases as the static converter just allows it to start.

A phase perfect is closer to a vfd but without the drawbacks (other than price)

For a single saw a $250 vfd makes more sense than a rpc or a PP

[Mark e Kessler]

A PP is a digital converter not a static converter which is not what you are looking for. Did you not go the PP website, they have tons of info A new 10pp is probably around 4k, metal working forums are a good place for used ones. For rotary go to American rotary’s website they have tons of information. Probably around $1500 for a 20hp which will run 10hp. Ypu can probably get a used Rotary for $500 or under and you can also make them yourself.

Jared makes a good point, I didn’t even think of a VFD for a single solution could be good but if you are planning for the long ter a PP or rotary makes more sense but could be a way to just start with the saw for low money

[Kurt Wyberanec]

Hi Mark, I've looked at the site and learned quite a bit... when looking at this cheap o product i just saw I didn't realize there was a difference since they call it a digital static convertor... the pp just says digital convertor guess I didn't realize there is something different going on and being this stuff is pretty new to me I'm trying to learn the differences.

[Kurt Wyberanec]

What 3 phase machines do you plan to run?

Mentioned looking at a new saw.. slider... outside of that no current plans though have a line on a seemingly great deal on a wide belt but would only be buying it because of the deal and possible future (not current) needs... biggest downside would be where to put it so it's not in the way lol.

[Kurt Wyberanec]

The phase perfect isn't a static converter. The $89 version (and they all basically) are just a start capacitor. The motor only runs on 2 phases as the static converter just allows it to start.

A phase perfect is closer to a vfd but without the drawbacks (other than price)

For a single saw a $250 vfd makes more sense than a rpc or a PP
Oh boy, now something new to consider! The price point is definitely more attractive... what can you tell me? Brands to look at? Size needed? Etc. This would be for a slider probably 5- 7.5hp plus scoring motor. Thanks!

[Phillip Mitchell]

Seems like there may be some fundamental misunderstandings in your original post. Not sure if I have the time to speak to all of them and there are more knowledge folks on here that can speak to 3 phase conversion as well.

Here are some things you will want to think about directly and assess. Giving answers in this thread will help folks give accurate recommendations and answers because it’s a bit of shooting in the dark without details.

How big of a motor (s) are you planning to run with a phase converter? Ideally the answer would be in amps but HP ratings will get you close.

What are the details of your current electrical service? Ie: how many amps is your current single phase 240v panel? Are we assuming that you are a 1 person shop and will only be using 1 machine with a dust collector simultaneously? What size motor on the DC?

You can essentially figure on feeding twice the amount of 220V single phase amps into a phase converter than what you will get on the output 3 phase side. Example - I have a Kay Phasemaster rotary phase converter that will start up to a 10 hp 3 phase motor. I have 4 gauge wire coming from a 60 amp breaker in my single phase 240v panel going into the phase converter which can produce ~30 amps 3 phase at 240V. A 10 hp 3 phase motor could be rated at ~25-30 amps at 240V so hence the capacity to start and run that size motor.

A Phase Perfect compared to a cheap static phase converter is complete apples to
oranges and not at all a like comparison. Phase perfect is a high quality digital converter that produces a totally balanced voltage output across all 3 lines and is designed to accommodate electronically sensitive equipment / motors (think CNC, highly automated saws/shapers/etc with a lot of electronics on them)

A simple static phase converter like your talking about for $85 is something that can start a 3 PH motor (often at a reduced / limited capacity) but it not set up to run it continuously on proper 3 phase power. A rotary phase converter is designed to start and run 3 phase machines continuously on relatively balanced voltages for extended periods of time and typically does so with the use of an idler motor that helps generate the 3rd leg of the 3 phase. Some of them are more balanced than others across all 3 lines. My Kay typically has 2 lines at whatever my incoming utility voltage is (248v last time I checked) and 3rd “wild” leg at around 275V. This isn’t really a problem with simple machines and motors but may not be the best choice for more sensitive motors / controls like CNCs, etc. I have simple machines and motors and it works great for me.

With the Phase Perfect product, you’re paying for a few things - simplicity of setup, extremely balanced voltages for use with sensitive motors, and a relatively compact and well engineered package / system that often times doesn’t need anything else.

Rotary phase converters can be similarly equipped and be just as effective.

I have ~$1500 or less into my system that will start a 10 hp motor that includes a 3 phase MLO subpanel with separate breakers and receptacles and a transformer so I can keep all my 3 PH machines plugged in at once and run multiple motors simultaneously (shaper with power feeder for example)

You can also do the same thing with a VFD though that would be for only 1 motor and typically the VFD does not want any machine controls/switches in between the motor and the VFD wiring so it then becomes your controller for turning the motor on and off. Large VFDs (over 5 HP) can get expensive, though still probably cheaper overall for just one big one compared to a RPC or Phase Perfect setup.

I do not notice additional electrical expense from running my RPC and it’s attached idler motor, FYI.

I don’t know if I answered everything but hopefully this helps?

edit: I see Jared and mark jumped in while I was typing my novel, but hopefully this helps your understand the differences and more of what you need.

If your potential saw has separate main and scoring blade motors (many do) then you will likely need a separate VFD / control for each, though scoring motors are small and VFD will be pretty cheap for that.

[Malcolm McLeod]

Oh boy, now something new to consider! The price point is definitely more attractive... what can you tell me? Brands to look at? Size needed? Etc. This would be for a slider probably 5- 7.5hp plus scoring motor. Thanks!

A VFD on a slider would be possible, but lots of work to implement. You could easily run both the main motor and scorer on a separate VFD, but it is not a matter of installing a VFD ahead of the 'saw' and the VFD delivers 3-phase power to the saw. You cannot have a relay (the typical OEM, as-supplied, electro-mechanical starter) in the line between the VFD and the motor.

Then if you install a VFD, you have to determine how to interface to it: start / stop / speed. You basically have to gut the OEM electrical system of the saw and rebuild it around the VFD(s). Doable, but make sure you know what you're getting into.

[Bruce Wrenn]

Oh boy, now something new to consider! The price point is definitely more attractive... what can you tell me? Brands to look at? Size needed? Etc. This would be for a slider probably 5- 7.5hp plus scoring motor. Thanks!


Look at some of the machinest web sites. They have TONS of info on phase converters, include shop builds. The most expensive part of a shop build, isn't the motor, but the wiring and controls associated with it. Used 3 phase motors can be purchase at salvage yards for less then $0.25 per pound. Most 3 phase motors were removed from service due to bearing failure. Ten bucks worth of bearings, and you are good to go for a lifetime. About twenty years ago, I built a rotary converter for my neighbor, using a three phase motor and a "pony motor" to start it running. The pony motor can be replaced with capacitors and a start switch. Throw the power switch on, and push the button. If power fails, magnet relay kicks out to protect motor from frying due to lack of rotation.

[Jared Sankovich]

A VFD on a slider would be possible, but lots of work to implement. You could easily run both the main motor and scorer on a separate VFD, but it is not a matter of installing a VFD ahead of the 'saw' and the VFD delivers 3-phase power to the saw. You cannot have a relay (the typical OEM, as-supplied, electro-mechanical starter) in the line between the VFD and the motor.

Then if you install a VFD, you have to determine how to interface to it: start / stop / speed. You basically have to gut the OEM electrical system of the saw and rebuild it around the VFD(s). Doable, but make sure you know what you're getting into.

Didn't realize when I originally posted it was a multi motor slider. 2 vfds and the control wiring would make all the other options easier. Not to mention the price for a 7.5-10hp vfd would be $650 then another $200 for the scoring saw vfd.

[Malcolm McLeod]

Didn't realize when I originally posted it was a multi motor slider. ...

I've been following Mr. Wyberanec's other thread on sliding saws, so I made the leap that "saw" was a slider... :D.

[Charles Coolidge]

I opted for a rotary phase converter from American Rotary, the only phase converted approved by HAAS to run their CNC machines.

[Bradley Gray]

I'm currently running a Kay rotary 10 hp rated to start 10 hp and run 20. I got a deal I couldn't refuse on it about 5 years ago.

Before that I used a homemade RPC with 7 hp idler started with capacitors.

I have 13 3 phase machines connected.

The simplest system I've seen was a machinist friend - a 10hp 3 phase motor with a flat belt pulley that Ron spun up to speed with his foot every morning.

[Carl Beckett]

You are in the Hartford/Boston area. RPC's come up on CL from time to time, with a 10hp being about $500. Be patient and buy a used one and it resolves all your problems.

[Mitch schiffer]

I prefer vfds if you are just going to have 1 or 2 3 phase Machines. I have several 7.5hp vfds in my shop and I have been happy with them.

[William Hodge]

I have a 20 hp rotary phase converter I start with a nut driver in an electric drill. The drill gets the motor spinning at 1700 rpms, then I throw a big old knife switch to energize the motor. Removing the nut driver from the shaft before throwing the switch prevents having a 20 hp Dewalt electric drill flopping around in my hands.
Cost:
20 hp motor: probably a few hundred dollars
Big old knife switch: free
70 amp breaker in the main panel, conduit, 3 phase panel, and big ass wires: $500. for an electrician to install it, 20 years ago

[Maurice Mcmurry]

That boat builder on YouTube that my daughter thinks is sooo cute has a nifty pony motor, with some safety measures, for starting his.

[William Hodge]

That boat builder on YouTube that my daughter thinks is sooo cute has a nifty pony motor, with some safety measures, for starting his.

Do you have a link?
Hanging on to a jumping electric drill while I had cracked ribs was character building I didn't need.

[Michael Schuch]

I built my own 10hp balanced rotary phase convertor about 30 years ago. It uses capacitors to initially start the idler motor.

I really like being able to bring home a new 3ph machine, plug it into the phase convertor, have it fire up immediately and be ready to go. I did not run 3 phase wiring throughout my shop though so it is somewhat cumbersome to unplug one 3ph machine then plug in another one when using multiple machines in a project. So most of my 3 phase machines now have VFD's on them which is somewhat involved but it is nice to be able to plug them into any available 220v outlet.

[Maurice Mcmurry]

14:40 minutes in


https://youtu.be/oKEd3ro3Z4I

[Maurice Mcmurry]

Dad has a giant phase convertor. It is capacitor start. It is on a 60 amp breaker. The junction / capacitor box is huge. It was made by the guy who kept the grain elevators, the Wonder Bread bakery, the grain driers on several thousand silos and grain bins, and lots of other stuff, working for 50 years or more. We sure do miss him. Which one of the three sons will get the phase convertor? I hope it is me.

[Kurt Wyberanec]

Spoke to someone at PP today and got some info....couple of quick questions.....

Why do I need an 80 amp breaker for a 10hp PP that only draws 30 amps? Am I missing something there?

2) Can one of you explain to me how I could make a VFD work for this machine? I guess I don't quite understand how it becomes a phase convertor so that I can run a 3p machine off my single power?

Thanks everyone!

[Bill Dufour]

One advantage of a VFd is it can be underrated. IOW a 5hp VFD can run a 7hp motor just fine. But that motor will only put out 5 hp. Any other type of converter must be big enough and be balanced to handle the motors full hp. This gives you options to buy a smaller VFD for now and latter buy a bigger, more expennsive, one and reuse the old one for a proper size motor. A vfd can also be derated and that same 5hp VFD can run a one hp motor when you buy the 7.5 hp vfd you really wanted but ahd to wait for a good price.
Bill D.

[Kevin Jenness]

2) Can one of you explain to me how I could make a VFD work for this machine? I guess I don't quite understand how it becomes a phase convertor so that I can run a 3p machine off my single power?

Here's an explanation of how it works https://vfds.com/blog/can-a-vfd-convert-single-phase-power-to-three-phase/

You can't have any switching between the vfd and motor, so you have to bypass the machine's stock magnetic starter. If you have a separate scoring motor you will need two vfds. A vfd allows for controlling a number of factors like speed, ramp-up/down time, reversing, remote on/off switches and so on, which are overkill for a table saw.

A static phase converter is a simple economical alternative for an overpowered machine. I have a 3hp slot mortiser that has been running on a static converter for 30 years without problems. I would be hesitant to run a tablesaw on one, but if you were always cutting 3/4" material with a 10 hp saw, 2/3 of the rated power would still be more than enough.

As several people have said, a rotary converter allows for running multiple machines and does not have to be expensive. I use one for my slider and planer, while I have vfds on my lathe, edge sander and exhaust fan, all of which benefit from adjustable speed.

[Carl Beckett]

Here's an explanation of how it works https://vfds.com/blog/can-a-vfd-convert-single-phase-power-to-three-phase/

You can't have any switching between the vfd and motor, so you have to bypass the machine's stock magnetic starter. If you have a separate scoring motor you will need two vfds. A vfd allows for controlling a number of factors like speed, ramp-up/down time, remote on/off switches and so on, which may be overkill for a table saw.

A static phase converter is a simple economical alternative for an overpowered machine. I have a 3hp slot mortiser that has been running on a static converter for 30 years without problems. I would be hesitant to run a tablesaw on one, but if you were always cutting 3/4" material with a 10 hp saw, 2/3 of the rated power would still be more than enough.

As several people have said, a rotary converter allows for running multiple machines and does not have to be expensive. I use one for my slider and planer, while I have vfds on my lathe, edge sander and exhaust fan, all of which benefit from adjustable speed.

This mirrors my experience. Even a static phase converter has a place, I ran a large belt sander off one for years with no problems at all. Variable speed via VFD can be nice for certain equipment. I wouldnt use it on a table saw nor a planer so that doesnt click for me. For me, once I have to start rewiring the base machine and using multiple VFDs to drive multiple motors on the same machine, it becomes more complex than I want (in part because I might want to sell the machine some day and DIY modified machines are always suspect). The RPC simply gives you 3 phase power to tap into and run whatever you want.

[roger wiegand]

VFDs don't play well with electronics, so if your plans include machines that incorporate electronic components that would drive a decision towards the RPC or PP. I installed an RPC from American Rotary and have been quite happy with it except for the irritating whine it makes-- the whole building seems to resonate with it. I'm wishing I'd bought the outdoor enclosure for it so I could get it out of the shop. OTOH, I do remember to turn it off when it's not in use!

[Maurice Mcmurry]

Dads roto-phase will run "Belching Beulah". The two drums each have very big motors. The oscillator and feed motor is a a bit smaller but also very big.

474032

[Phillip Mitchell]

Spoke to someone at PP today and got some info....couple of quick questions.....

Why do I need an 80 amp breaker for a 10hp PP that only draws 30 amps? Am I missing something there?

2) Can one of you explain to me how I could make a VFD work for this machine? I guess I don't quite understand how it becomes a phase convertor so that I can run a 3p machine off my single power?

Thanks everyone!

1) Typically it’s a 2:1 ratio, but each converter is slightly different and there may be a bit of CYA (cover your ass) factor in there and they have decided to up size to the nearest bigger breaker. Did you ask them why you need 80 amps single phase for 30 amps 3 phase? They would be able to tell you more directly than any of us, I suspect.

2) Several folks including myself have indicated that wiring in a VFD in your particular case is almost certainly more trouble / work / modification than its worth. You would do well to save a VFD for a smaller amp, less switch heavy, single motor machine that can benefit from speed control and external switching / controls.

[Jared Sankovich]

Spoke to someone at PP today and got some info....couple of quick questions.....

Why do I need an 80 amp breaker for a 10hp PP that only draws 30 amps? Am I missing something there?

2) Can one of you explain to me how I could make a VFD work for this machine? I guess I don't quite understand how it becomes a phase convertor so that I can run a 3p machine off my single power?

Thanks everyone!

It draws more than 30amps. If it outputs 30amps 3ph (10hp) it's at least 30x1.8 for the input (plus any losses)

[Kurt Wyberanec]

OK, so this sounds like I will remove VFD from my plan. So that leaves Static, Rotary, and Digital (Phase Perfect)...

I am still trying to understand how this would have to be hooked into my current subpanel...what size breaker I'm going to need, and if the panel is big enough for it. Some of you said it is 1.8 to 2x conversion...when I asked PP about this they told me that it will draw about the same amount as the saw, then I asked why the breaker needs to be so big and they basically said it's just in case protection and that it really only makes a difference for the start up. They claim virtually no efficiency loss. This doesn't quite make sense to me...the unit has to be using power to make some I would think (hence the multiples some of you mention) which makes sense to me but contradicts what they said. At the end of the day I'm trying to figure out if this is going to require me to have an electrician upgrade my panel to handle more amps and if that's the case then it just continues to increase the expense.

I also don't quite understand whether or not the cheap static convertors can work and if they have any potential risks. Again, I'm really thinking this is going to be a single tool most likely with a separate scoring motor and that would probably be a 5-7.5hp main and .5 to 1hp scorer. There's an off chance I would go for a bigger saw if the deal were right but I just don't think I need it at least at this point in my shop.

Again, any thoughts much appreciated. Thanks!

[Jared Sankovich]

OK, so this sounds like I will remove VFD from my plan. So that leaves Static, Rotary, and Digital (Phase Perfect)...

I am still trying to understand how this would have to be hooked into my current subpanel...what size breaker I'm going to need, and if the panel is big enough for it. Some of you said it is 1.8 to 2x conversion...when I asked PP about this they told me that it will draw about the same amount as the saw, then I asked why the breaker needs to be so big and they basically said it's just in case protection and that it really only makes a difference for the start up. They claim virtually no efficiency loss. This doesn't quite make sense to me...the unit has to be using power to make some I would think (hence the multiples some of you mention) which makes sense to me but contradicts what they said. At the end of the day I'm trying to figure out if this is going to require me to have an electrician upgrade my panel to handle more amps and if that's the case then it just continues to increase the expense.

I also don't quite understand whether or not the cheap static convertors can work and if they have any potential risks. Again, I'm really thinking this is going to be a single tool most likely with a separate scoring motor and that would probably be a 5-7.5hp main and .5 to 1hp scorer. There's an off chance I would go for a bigger saw if the deal were right but I just don't think I need it at least at this point in my shop.

Again, any thoughts much appreciated. Thanks!

If it pulls 22 amps 3ph (assuming 8ish combined hp) it will be 22x1.732(single to 3ph conversion factor) so 38.104 amps from the panel.

You are overlooking the fact that single phase amperage and 3 phase amperage are not equal (hence the 1.732 multiplication factor when converting from 3ph motor plate to single phase input requirements.

[Erik Loza]

Kurt, I'm going to float this out there: Feel free to accept or reject as you like. I've been witness to this exact conversation with hobbyist ww'ers MANY times and it invariably goes one of two ways.

#1.) After running through all the mental gymnastics of what it would look like to actually acquire your ideal used machine (which often doesn't exist), and after running through all the mental gymnastics of getting a phase converter installed, the customer ends up back where they started and just buys a new 1-phase machine.

#2.) After running through all the mental gymnastics above, the customer decides it was just too much and ends up sticking with whatever smaller machines they have and never actually buy anything after all.

Not saying this is necessarily you, Kurt, just that I've seen the this scenario unfold many times in the past. Yes, there are some hobbyist owners here with three-phase machines and converters in their home shops and that's great but they would definitely be in the minority and more importantly, from a woodworking perspective, there is nothing you would be doing that a decent single-phase saw in the 4-5HP range couldn't accomplish. Your wallet and you should do what you want but from a buyer's standpoint, I think probably will find that by the time your search is over, it might even be cheaper to just get a 1-phase machine and be done with it so you can get on to actual woodworking. Again, just an opinion from a different perspective and good luck in your search.

Erik

[Jared Sankovich]

Kurt, I'm going to float this out there: Feel free to accept or reject as you like. I've been witness to this exact conversation with hobbyist ww'ers MANY times and it invariably goes one of two ways.

#1.) After running through all the mental gymnastics of what it would look like to actually acquire your ideal used machine (which often doesn't exist), and after running through all the mental gymnastics of getting a phase converter installed, the customer ends up back where they started and just buys a new 1-phase machine.

#2.) After running through all the mental gymnastics above, the customer decides it was just too much and ends up sticking with whatever smaller machines they have and never actually buy anything after all.

Not saying this is necessarily you, Kurt, just that I've seen the this scenario unfold many times in the past. Yes, there are some hobbyist owners here with three-phase machines and converters in their home shops and that's great but they would definitely be in the minority and more importantly, from a woodworking perspective, there is nothing you would be doing that a decent single-phase saw in the 4-5HP range couldn't accomplish. Your wallet and you should do what you want but from a buyer's standpoint, I think probably will find that by the time your search is over, it might even be cheaper to just get a 1-phase machine and be done with it so you can get on to actual woodworking. Again, just an opinion from a different perspective and good luck in your search.

Erik

I see the mental gymnastics is the common problem there.

So you didn't see a lot of people just buy stuff on a whim, drag it home and figure out how to make it work after the fact?

[Erik Loza]

So you didn't see a lot of people just buy stuff on a whim, drag it home and figure out how to make it work after the fact?

Nope.... The whole "Gee, I could score a sweet deal on a 3-phase machine?" exercise is like the Rumspringa of hobbyist woodworkers. Statistically speaking, most will come back to 1-phase. Not telling the OP what he should/ought to do, just sharing what my experience has been through the years.

Erik

[Phillip Mitchell]

This is a pretty easy problem to solve. I get that it’s unfamiliar at first and there are some questions / variables, but you’ve had a lot of solid and specific advice in this and other threads. Doesn’t need to be more complicated than necessary.

There are tons of used machines out there that will fit the bill and most are 3 phase within the category that you’re looking at. Finding a used single phase machine is much less likely, IMO. Based on the other thread, new and full stroke seems to be out of the budget.

There is an incredible amount of value in having the option to run 3 phase machines. I have outfitted my shop with (8) used 3 phase machines for roughly around the same cost of a full stroke well option premium Euro slider. I would likely not be woodworking if I thought I needed to buy machines new. Of course everyone should do what works for them, but if you are on a budget, trying to stretch it and want really high quality machines you would do well to familiarize yourself with the right phase converter setup for your needs and dig in.

[Kurt Wyberanec]

Kurt, I'm going to float this out there: Feel free to accept or reject as you like. I've been witness to this exact conversation with hobbyist ww'ers MANY times and it invariably goes one of two ways.

#1.) After running through all the mental gymnastics of what it would look like to actually acquire your ideal used machine (which often doesn't exist), and after running through all the mental gymnastics of getting a phase converter installed, the customer ends up back where they started and just buys a new 1-phase machine.

#2.) After running through all the mental gymnastics above, the customer decides it was just too much and ends up sticking with whatever smaller machines they have and never actually buy anything after all.

Not saying this is necessarily you, Kurt, just that I've seen the this scenario unfold many times in the past. Yes, there are some hobbyist owners here with three-phase machines and converters in their home shops and that's great but they would definitely be in the minority and more importantly, from a woodworking perspective, there is nothing you would be doing that a decent single-phase saw in the 4-5HP range couldn't accomplish. Your wallet and you should do what you want but from a buyer's standpoint, I think probably will find that by the time your search is over, it might even be cheaper to just get a 1-phase machine and be done with it so you can get on to actual woodworking. Again, just an opinion from a different perspective and good luck in your search.

Erik


This is a pretty easy problem to solve. I get that it’s unfamiliar at first and there are some questions / variables, but you’ve had a lot of solid and specific advice in this and other threads. Doesn’t need to be more complicated than necessary.

There are tons of used machines out there that will fit the bill and most are 3 phase within the category that you’re looking at. Finding a used single phase machine is much less likely, IMO. Based on the other thread, new and full stroke seems to be out of the budget.

There is an incredible amount of value in having the option to run 3 phase machines. I have outfitted my shop with (8) used 3 phase machines for roughly around the same cost of a full stroke well option premium Euro slider. I would likely not be woodworking if I thought I needed to buy machines new. Of course everyone should do what works for them, but if you are on a budget, trying to stretch it and want really high quality machines you would do well to familiarize yourself with the right phase converter setup for your needs and dig in.

Hey all, Erik, I definitely see the logic of what you're saying. And I can possibly see myself falling into scenario #1...I will be doing something so I won't just be falling back to what I have. That said, I'm one of those people who really wants to get the most out of their budget. I'm not afraid of used and I don't mind putting work and time in, but it all has to be worth it....in other words not just to save a few bucks because there are new machines that fall into the budget, but rather if I do go used, it's not going to be to lower the overall cost but rather to get something that is much more substantial than the new machine would be. It's like buying a luxury car....new lot of money, 5 years old often cheaper than a new Toyota if taken care of you still have the nice luxury car for a long time. A big part of me wants new but the big problem with things like this is that it's not like a car, because with a car I could just go to every dealership, see what I like and go for it, but saws are seemingly all going to be bought unseen or touched at least for me, so it's a big thought process.

Back to the topic at hand.....can anyone tell me what is wrong with the inexpensive static convertors? I just want to understand why I should be looking for either rotary or a PP over the others? Also, the rotary units seem to be significantly less efficient than say the PP but also cost significantly less. A saw that I'm currently looking at has a 9hp motor and the owner told me he uses a 20hp American Rotary and sent me the link and info and it works perfectly and easy to install. Now I don't know much more than that but 1500 new is a lot less than 2500+ for a 7.5 or 10 PP so trying to understand what the downsides are as best as possible.

Thanks again all!

[Phillip Mitchell]

It’s confusing because different manufacturers advertise and rate their units differently. Some companies advertise HP on the size of the idler motor itself (American Rotary) and not necessarily what size 3 ph motor it will start. Others (PP, Kay) advertise HP based on the largest size 3 ph motor it will start. You have to become familiar with the different companies and how they advertise and read the specs.

I’ll let someone else tackle the static converter question. It’s my understanding that you will only get up to 2/3 of the amps/HP out of your motor with that setup. I also thought it was for help starting the motor and then once it’s started you are only getting 2 out of the 3 legs of the the line power and hence not actually operating on true 3 phase, but I don’t have personal experience so not totally sure and the above may not be correct. Seems a poor choice for a nice slider with a big motor that you may want full capacity of.

[Kevin Jenness]

can anyone tell me what is wrong with the inexpensive static convertors?

Essentially, the motor is de-rated by 1/3. If you need the full power of the motor a static converter is a poor choice. A saw with a 9 hp motor would probably be fine, one with a 3 hp motor not so much. It depends on usage.

https://www.northamericaphaseconverters.com/resources-assistance/static-phase-converter-faqs/

[Jared Sankovich]

Nope.... The whole "Gee, I could score a sweet deal on a 3-phase machine?" exercise is like the Rumspringa of hobbyist woodworkers. Statistically speaking, most will come back to 1-phase. Not telling the OP what he should/ought to do, just sharing what my experience has been through the years.

Erik

I was really surprised by that at first but the more I think about it thr more it actually makes sense. The owwm group and the have a machine comissioned group tend to be on opposite ends of the spectrum (as Hobbyists)

[roger wiegand]

I was really surprised by that at first but the more I think about it thr more it actually makes sense. The owwm group and the have a machine comissioned group tend to be on opposite ends of the spectrum (as Hobbyists)

Well, I just did the math. The nearly new, almost perfect, all the bells and whistles used 3 PH 16" J/P I found plus a RPC to run it was a couple thousand dollars cheaper than buying the same machine new. Of course, being cheap, I would have bought a lesser machine new. Having had it for a couple of years I'm really happy to have features like the motorized lift.

That said, I didn't think about adding a RPC to the shop until after I found the machine. Now, of course, I'm free to add other 3ph machines as I like.

[Carl Beckett]

can anyone tell me what is wrong with the inexpensive static convertors?

Essentially, the motor is de-rated by 1/3. If you need the full power of the motor a static converter is a poor choice. A saw with a 9 hp motor would probably be fine, one with a 3 hp motor not so much. It depends on usage.

https://www.northamericaphaseconverters.com/resources-assistance/static-phase-converter-faqs/

Absolutely positively nothing wrong with the static converters. I ran a large belt sander on one for a few years with zero issues. I was never close to needing the full HP rating of the machine. It cost me $100 used off craigslist for the converter, and I sold it for what I paid for it once I installed a RPC (which I paid $500 for).

Static phase converters will work in many cases, especially hobbiest who are not taxing their machines to max HP.

Having said that, I agree with Erics comments.

[Kurt Wyberanec]

Absolutely positively nothing wrong with the static converters. I ran a large belt sander on one for a few years with zero issues. I was never close to needing the full HP rating of the machine. It cost me $100 used off craigslist for the converter, and I sold it for what I paid for it once I installed a RPC (which I paid $500 for).

Static phase converters will work in many cases, especially hobbiest who are not taxing their machines to max HP.

Having said that, I agree with Erics comments.

If I end up with about a 5hp saw then I could see myself getting close to taxing it only once in a while, say ripping 2" hardwood, but that's somewhat rare for me right now and currently am using a 3hp single phase. If it's 7.5 or great I doubt I will ever tax it.

On a different question is a Static convertor something you need to have an electrician install or is it something you can do yourself if slightly comfortable in your panel? 2nd, since they are less efficient do you need a bigger breaker for them, than say RPC or PP?

Thanks.

[Kevin Jenness]

My slot mortiser has a 3hp 3 phase motor. The static converter is a small box mounted on the machine and runs on a circuit with 12 ga wire and a 20 amp breaker. A single phase 3 hp motor typically draws about 17 amps @ 230 volts. I don't know that there is any loss of efficiency in using a static converter - perhaps one of the engineers here can comment.

I am not an electrician, and I didn't wire that converter, but I have wired up two VFDs and my rotary converter setup.

From the link I posted earlier

Mounting and Installation
Where can I install a static phase converter?
Generally it is mounted close to your equipment. It can be mounted directly to the equipment as long as there isn’t excessive vibration. A NAPCco static converter is equipped with two mounting brackets for easy installation.
Is a static phase converter easy to wire?
Absolutely, a NAPCco static phase converter has a simple three wire connection. A junction box is located on top of the converter’s enclosure wire a terminal block for wiring inside.
What size circuit breaker/fuse and wire do I use?
A circuit breaker switch (https://www.northamericaphaseconverters.com/product/circuit-breaker/) and wire is determined by the size of the static phase converter and size of the motor you are starting. A recommended circuit breaker/fuse and wire chart is available in the operation and installation manual (https://www.northamericaphaseconverters.com/wp-content/uploads/2013/07/NAPCES-Static-Installation-Manual.pdf)

[derek labian]

Kurt, I'm going to float this out there: Feel free to accept or reject as you like. I've been witness to this exact conversation with hobbyist ww'ers MANY times and it invariably goes one of two ways.

#1.) After running through all the mental gymnastics of what it would look like to actually acquire your ideal used machine (which often doesn't exist), and after running through all the mental gymnastics of getting a phase converter installed, the customer ends up back where they started and just buys a new 1-phase machine.

#2.) After running through all the mental gymnastics above, the customer decides it was just too much and ends up sticking with whatever smaller machines they have and never actually buy anything after all.

Not saying this is necessarily you, Kurt, just that I've seen the this scenario unfold many times in the past. Yes, there are some hobbyist owners here with three-phase machines and converters in their home shops and that's great but they would definitely be in the minority and more importantly, from a woodworking perspective, there is nothing you would be doing that a decent single-phase saw in the 4-5HP range couldn't accomplish. Your wallet and you should do what you want but from a buyer's standpoint, I think probably will find that by the time your search is over, it might even be cheaper to just get a 1-phase machine and be done with it so you can get on to actual woodworking. Again, just an opinion from a different perspective and good luck in your search.

Erik

Thats good advice. There's another trap too; if you buy a 3-Phase converter at 240v, you may end up needing 480v for some equipment. The idea of buying another voltage doubling phase convertor or adding transformers is just more "mental gymnastics". (Note: talking about a machine that has a 480v VFD in it etc, not a motor that can be rewired)

[Phillip Mitchell]

You can find used transformers for pretty cheap and that solves the 480v issue. I found a 7.5 kVa 240 -> 480V barely used 3 phase transformer for $100 from a regional electrical supply after a few weeks of looking for a good deal somewhat locally.

Also, it’s not like you wouldn’t know the machine was 480v only...that would be something you’d assess and figure on prior to buying the machine.

Don’t get me wrong, there are some mental gymnastics with this stuff, and it does require either some effort and/or $ to put in place, but it’s relatively simple and the answers are out there and available if you look. If I can do it, anyone can.

[Bradley Gray]

3 phase 240v is very common on used industrial grade woodworking machinery, way more common than single phase. I have been fortunate to acquire machines from the golden age of American machine tools at crazy prices because of the 3 phase motors.

I set up my first RPC in 1977 based on a Fine Woodworking issue that showed up just in time to help me get my 32" Crescent band saw up and running. I bought an idler motor for about $20 and a couple capacitors and went on to add many more machines.

[derek labian]

You can find used transformers for pretty cheap and that solves the 480v issue. I found a 7.5 kVa 240 -> 480V barely used 3 phase transformer for $100 from a regional electrical supply after a few weeks of looking for a good deal somewhat locally.

Also, it’s not like you wouldn’t know the machine was 480v only...that would be something you’d assess and figure on prior to buying the machine.

Don’t get me wrong, there are some mental gymnastics with this stuff, and it does require either some effort and/or $ to put in place, but it’s relatively simple and the answers are out there and available if you look. If I can do it, anyone can.

You had better luck than I. I assed it and I couldn't find a new transformer at the rating I needed; after a week of talking to Wolf Automation, I gave up. I think it would have been price prohibitive anyway. I think that was Erik’s point. I went with a different SP model instead because it wasn't worth the effort or expense.

[Phillip Mitchell]

I guess it depends on your tolerance for searching. I’m always looking at/for any number of things or subjects so it’s only natural for me to pivot the focus to something new should it become a more pressing need.

I also don’t have a lot of extra cash so I do not typically buy things new unless there is no other option for months on end and even then sometimes go without or find another way out of necessity. If I was pricing new transformers (I did briefly) then that would have been a non-starter for me. The transformer I found for $100 used (and professionally tested) would have been well over $1k to buy new on the spot, so you can see the value in searching for a few weeks for good condition used.

[Carl Beckett]

Here is a question I wondered when I sold that static phase converter. Essentially all it is, is a capacitor bank that times out to be able to start the motor. I have heard some people start one machine and let it idle while running some different machine on the same circuit.

If you have a static phase converter, and then buy a used 3 phase motor to run as idler, do you then have a RPC? Any rewiring needed at all?

If so, then there is no down side to trying it out. If the SPC isnt enough for some reason then just add a used idler motor.

(on voltages: once I open up my shopping to 3 phase 208 v machines, it increases options a lot. I havent noticed as big a jump in available equipment between 200-400V ranges (meaning, I can almost always find what I am looking for in 200V ranges - so have never felt a need to bump to 400. And 208v 3 phase motors are pretty plentiful if I wanted to swap down))

[derek labian]

I guess it depends on your tolerance for searching... The transformer I found for $100 used (and professionally tested) would have been well over $1k to buy new on the spot, so you can see the value in searching for a few weeks for good condition used.

I agree. I did my electrical upgrade and I purchased everything on eBay because I knew what parts I needed, and I waited. Over a few months, I bought everything, almost all new, at 50-70% off the electrical supplier price.

What I was referencing above is a bit different. Let me give you another real-world example of some mental gymnastics.

I am going to purchase a machine. There are two variants; one single-phase, one 3-phase with more "whatever" and I want the "more". So I start trying to figure out how to do the 3-Phase work. Well, I have a 3-Phase converter; great, I'm all set, except wait, it needs 480v. Great, I'll just buy a transformer, but it's $1800 news. That's a lot, but maybe it's worth it, or perhaps I can find something cheaper. Since it's 480-volt, though, I'm going to need double the amperage. Is my digital converter going to be enough to run my new machine AND the machine it was purchased for? Maybe I should buy a voltage doubling phase converter just for this; how much are those? How much will the installation be? Perhaps there is a cheaper option? Let me ask Wolf for help. A week later, I purchased the single-phase machine to hell with it because the "more" no longer sounds that appealing.

The point is, if you know what you want, it's easy to wait for that good deal. However, if you are exploring a purchase and you get mired down in options, you are just as likely to buy nothing because all the research, pricing, investigation, and discussions are a colossal time suck. That's the mental gymnastics Erik speaks of.

[Phillip Mitchell]

480v configuration uses half the amps of 240v. It’s all math figuring out if the converter, etc can handle a certain load. I suppose you could call that mental gymnastics; it’s just part of putting all the pieces together. I’m not sure what a voltage doubling phase converter is? Why not use a transformer?

In my mind, if you’re going the RPC / digital converter route then it makes a whole lot of sense to size that converter up to the highest amperage capacity that you could imagine using and starting there. In my case it’s an RPC that puts out 30 amps at 220V 3 phase which can handle anything ~10 hp and below. This was not cost prohibitive to find used ($800 a few years back.) I can’t run a wide belt off of that but have no space for one anyway.

No way that I would pay $1800 for a new transformer when there are so many used examples out there for ~ 25 % of new but that’s just me, I suppose.

For me it all changed and opened up a lot of options once I found the 10HP RPC and brought it online. From there it’s pretty simple to assess what machines that come on to the radar are suitable choices or not. Before I had the RPC there was some confusion / stress about how I could make say, a 20” industrial planer work in my shop. This is the upside of committing to something like an RPC/etc that is sized for future “growth”. It really didn’t cost me that much to get it all in place and now the infrastructure is there and a known variable in the equation.

[Jared Sankovich]

The point is, if you know what you want, it's easy to wait for that good deal. However, if you are exploring a purchase and you get mired down in options, you are just as likely to buy nothing because all the research, pricing, investigation, and discussions are a colossal time suck. That's the mental gymnastics Erik speaks of.

I'm a fan of less thinking /pre planning. Buy the equipment, then figure out how to make it work (or move it) after its in the shop. Doing it that way also motivates you to finish the process since you have a large dead machine in the way if you don't. It hasn't failed me so far.

That is the reason I commented upthread that the mental gymnastics were the problem.

[derek labian]

480v configuration uses half the amps of 240v. It’s all math figuring out if the converter, etc can handle a certain load. I suppose you could call that mental gymnastics; it’s just part of putting all the pieces together. I’m not sure what a voltage doubling phase converter is? Why not use a transformer?

I was referencing the additional wattage for an existing 240v phase converter, over a SP source. If you don't have the wattage available, a transformer isn't going to help. Voltage Doubling Phase Converter (https://www.phaseperfect.com/enterprise/voltage-doubling/).


No way that I would pay $1800 for a new transformer when there are so many used examples out there for ~ 25 % of new but that’s just me, I suppose.

It was a story and I didn't buy new or used transformer. You are getting stuck on the details of the example and missing the bigger point about options, choices, and complexities leading to people walking away all together or just going SP.

[Leigh Betsch]

You all wear me out. It just ain’t that hard. I have a RPC wired into its own panel feeding multiple machines, a VFD wired into my Bridgeport which also provides soft start, reverse and variable speed. , and a static phase converter on the self from another shop.
It’s just not that hard. Hire someone if it’s above your skills.

[Phillip Mitchell]

You all wear me out. It just ain’t that hard. I have a RPC wired into its own panel feeding multiple machines, a VFD wired into my Bridgeport which also provides soft start, reverse and variable speed. , and a static phase converter on the self from another shop.
It’s just not that hard. Hire someone if it’s above your skills.

This is what I’ve been saying from the beginning, just in more (too many?) words.

The point I was trying to make is that there is a lot of information out there to solve the specific needs/problems you may have with phase and/or voltage conversion and anyone can do it and have a 3 phase capable shop with some combination of time, money and sweat equity depending on what you have more of to spare. It really isn’t as complicated as you might be led to believe.

[Leigh Betsch]

This is what I’ve been saying from the beginning, just in more (too many?) words.

The point I was trying to make is that there is a lot of information out there to solve the specific needs/problems you may have with phase and/or voltage conversion and anyone can do it and have a 3 phase capable shop with some combination of time, money and sweat equity depending on what you have more of to spare. It really isn’t as complicated as you might be led to believe.
Yes, Exactly

[Nick Crivello]

First is thanks to some help from Phillip Mitchell I've gotten an American Rotary AR-20 up and running several 3ph machines via a 3ph load center.

Here's my quick question:

I got the AR-20 as it is rated for 10hp machines, such as the 7.35kw Felder slider I picked up. However can it start and run two machines that exceed it's 10hp rating?

Datasheet is here:

https://www.americanrotary.com/pdfviewer/?pdf=3322

max starting current: 28amps/10hp
max running current: 56amps/20hp

Can I start and run that 24amp Felder saw and a 7amp/3hp dust collector off the same AR-20? Or should I think about a vfd on a 220v line for the DC?

[Phillip Mitchell]

Hey Nick,

Good to hear from you and glad you got your 3 phase sorted out. I would tend to think that you could run those loads based on the amps. How many single phase 240v amps are coming in to the RPC?

The DC will probably be close to that 7 amp rating consistently, but beyond starting in-rush current and really heavy ripping, for example, I don’t see the saw pulling 24 amps continuously. If it doesn’t work and isn’t quite enough then a 3HP VFD is cheap enough to add on.

I would imagine you will be fine, though. I don’t really run multiple 3 PH motors simultaneously in my shop (DC is single phase) except a shaper and power feeder, but I have read of folks using their RPC as follows to start a harder to start motor that may be close to the capacity of the RPC - start the smaller motor first with the RPC. Then, after that’s running start the larger motor and the smaller motor already running can actually help the RPC start the more difficult load. It’s certainly worth a try and I’d imagine it would handle it fine if you have 60 amps Single phase incoming / 30 amps 3 phase output.

[Nick Crivello]

Hey Nick,

How many single phase 240v amps are coming in to the RPC?



I have a 60amp breaker feeding the RPC. Thinking it'll work so long as both machines aren't turned on at the same time.

Nick

[Bill Dufour]

A disk sander or big grinder can be used as an extra idler motor if needed. I suppose a dc fan motor may work. All three have no moving parts bedsides the motor to wear.
Bill D

[Jerome Stanek]

The old carnys used to pull start their motors with a rope I used to work for a printing company and we printed a bunch of hints and facts for doing stuff to get by.

[Jerome Stanek]

I remember back in 1964 my dad needed a phase converter to run his water pumps. An old electric repair man made him one the GE said could not be done. Worked for many years until he bought a new boiler. The same old guy made him a rotary phase converter by adding a floating motor. Pumps were 15 and 30 HP and boiler was 7 1/2 HP so the floating motor would take the shock of starting it.

[Jonathan Jung]

Happily running an American Rotary ADX 30hp for my wide belt sander and jointer. Very low power consumption, quiet, good customer service. I looked hard at digital units like the Phase Perfect and decided the longevity, simplicity, and product support of the American Rotary was worth saving cash for.

[Mark e Kessler]

the 10hp PP puts out 36a 3phase so you need an 80a single phase supply. You can run less to it and the available output will be less. I think mine is fed by 60a because it’s the breaker i had on hand. Everything is wired for full load so i can up the breaker at a later date if needed but that hasn’t happened yet…


Spoke to someone at PP today and got some info....couple of quick questions.....

Why do I need an 80 amp breaker for a 10hp PP that only draws 30 amps? Am I missing something there?

2) Can one of you explain to me how I could make a VFD work for this machine? I guess I don't quite understand how it becomes a phase convertor so that I can run a 3p machine off my single power?

Thanks everyone!

[Kurt Wyberanec]

the 10hp PP puts out 36a 3phase so you need an 80a single phase supply. You can run less to it and the available output will be less. I think mine is fed by 60a because it’s the breaker i had on hand. Everything is wired for full load so i can up the breaker at a later date if needed but that hasn’t happened yet…

Good to know, and that's one of the big questions I had, was how big the breaker needs to be on the single phase panel. So here's another question, does the PP draw anything unless the machine attached is drawing something? And also, let's say my saw says 25a...that's 25a 3 phase right, and so how much draw does that put on the single....someone said something like 1.7 so that's around 45....now that typical 25 saw....is that like a peak load or is that what it's drawing just running under typical load, say cutting a sheet of ply? My concern here is that I have only a 60a breaker into my subpanel....my shop lights and air cleaner as well as some of my 115 outlets are on the main panel....but most of my machinery is plugged into the panel...in which case I typically only run 1 machine and the DC at the same time. The DC is a 5hp so will I be able to use one of these saws with numbers like that or am I going to have to upgrade my panel to be larger? I know you're probably not an electrician, so this is all experience and opinion based (I don't want to call the electrician for answers because I am sure they will start costing me money before even buying something lol).

Thanks

[Mark e Kessler]

1st thing to check is the wire size feeding that subpanel and the breaker that feeds it, the wire may be able to carry more than the 60a like in my situation.

3p output is 1/2 single p input. The PP itself draws virtually nothing when its idle or when you are running machines.

I only have 60a going to my shop and all the lights are on, the air compressor can kick on and at the same time i can start a 7.5 hp 3p saw and a few seconds later a 1p 3hp dust collector and while all that is running i can start my single phase ad941 which i think is 3-4 hp AND while all of that is running i have started my 1p mm16 which i think is 3.5hp. And of course there are battery chargers and tasks lights on as well.



Good to know, and that's one of the big questions I had, was how big the breaker needs to be on the single phase panel. So here's another question, does the PP draw anything unless the machine attached is drawing something? And also, let's say my saw says 25a...that's 25a 3 phase right, and so how much draw does that put on the single....someone said something like 1.7 so that's around 45....now that typical 25 saw....is that like a peak load or is that what it's drawing just running under typical load, say cutting a sheet of ply? My concern here is that I have only a 60a breaker into my subpanel....my shop lights and air cleaner as well as some of my 115 outlets are on the main panel....but most of my machinery is plugged into the panel...in which case I typically only run 1 machine and the DC at the same time. The DC is a 5hp so will I be able to use one of these saws with numbers like that or am I going to have to upgrade my panel to be larger? I know you're probably not an electrician, so this is all experience and opinion based (I don't want to call the electrician for answers because I am sure they will start costing me money before even buying something lol).

Thanks

[Kurt Wyberanec]

Good to know! I will check the wire to the panel but I know the breaker is 60....oh and I have my mini split on it too.... forgot that.... in the winter it gets used often but once nighttime Temps get above 46 I only will use it a handful of times for ac in the summer.

[Carl Beckett]

When is the last time any of you tripped a breaker due to drawing too much current?

(it happens, but pretty rarely and most of us have put in excessive capability from what actually gets used...)

[Kevin Jenness]

When is the last time any of you tripped a breaker due to drawing too much current?

(it happens, but pretty rarely and most of us have put in excessive capability from what actually gets used...)

It happens to me when I forget to turn off the 3 phase compressor and it tries to start at the same time as the phase converter.

[Alan Lightstone]

So here's another question, does the PP draw anything unless the machine attached is drawing something?

Thanks

It does. If memory serves my 10HP Phase Perfect draws 375 watts when no machines are drawing a load. I actually have an alarm on my phone so that at 9PM I remember to check and see that it's off, so I don't draw that power overnight when forgetting to turn it off. I have one of my security cameras pointed at the digital display of one of the machines. If I see a readout, I forgot to turn off the PP.

That being said, it's not like that's a huge amount of energy. I just turn it off when not being used.

[Mark e Kessler]

PT10 uses 74w - 0.01c/hr, the American rotary AR20 says 0.06c/1hr which works out to around 300w. (@0.1855kwh)

Pulled info from PP and AR


It does. If memory serves my 10HP Phase Perfect draws 375 watts when no machines are drawing a load. I actually have an alarm on my phone so that at 9PM I remember to check and see that it's off, so I don't draw that power overnight when forgetting to turn it off. I have one of my security cameras pointed at the digital display of one of the machines. If I see a readout, I forgot to turn off the PP.

That being said, it's not like that's a huge amount of energy. I just turn it off when not being used.

[Maurice Mcmurry]

Dad has a giant phase convertor. It is capacitor start The capacitor bank looks like a 6 pack of Fosters.

475316

[Alan Lightstone]

PT10 uses 74w - 0.01c/hr, the American rotary AR20 says 0.06c/1hr which works out to around 300w. (@0.1855kwh)

Pulled info from PP and AR

I feel better now. Thanks, Mark. For some reason in my head that 375w figure got stuck.

Of course, 74 watts is about one floor of lighting in my house, so it's not nothing, but it's not 375. I'll forgive myself if I accidentally leave it on overnight.

[Bill George]

The old carnys used to pull start their motors with a rope I used to work for a printing company and we printed a bunch of hints and facts for doing stuff to get by.

Yes I was holding off commenting, a 3 phase motor for a RPC can be rope started in place of a single phase pony motor. Once the 3 phase motor is started and running on single phase it generates the 3d phase itself.

As a electrician who worked on industrial for many years and then crossed over to HVAC/R I build my own phase convertor as I had access to lots of used Run caps and start caps and used a potential or voltage relay to start the motor and then drop out the start cap. Generally speaking to make a RPC it needs to be larger than the run load motor by at least 1/3.

[John Erickson]

Just like Bradley's friend, I made my own 25 years ago. Using an old 10hp 220v 750 rpm 3ph motor connected to a small add-on 3ph panel with a manual switch, starting it each morning with a pull cord. I use it every day for all my 3ph equipment with no problems at all, my Altendorf F45 saw and Maho MH600P milling machine work flawlessly.
Although today I'd use a 15hp Lenze VFD feeding a 3ph sub panel connecting all equipment.

[Carl Beckett]

I have currently wired my phase convertor in conduit from the PC box to a 4 pin outlet, with a cord going to the machine.

There is a 50A socket in the wall for charging a car. There is a dryer pigtail into the PC box (I put that in at my last shop) to be able to disconnect.

I wonder if this will pass code.... but am about to find out. Anybody want to chime in on proper code for wiring a phase convertor?

[Rick Fisher]

I have a 20hp Phase perfect. I would recommend one only if you are going to run more than one machine with it.

Mine is a PP-20. Its wired to a 100 amp 230V single phase breaker. The PP creates about 56 - 58 amps of 230V PH-3 which runs to a Siemens Load centre panel. Meaning there is no main breaker, just a panel full of breakers.

Basically I walk in and snap the 100 amp breaker, wait 8 seconds and the contractor on the Phase Perfect "clunks ".. It makes a whistling sound and all the machines come to life.

The 3 phases panel feeds a Table saw, Planer, Jointer, Wide Belt, Edge sander, Shaper, Mortiser and edge bander. The advantage to this system is .. For example, I just took delivery of a new shaper. Its 3 phase. I install an appropriate breaker, run a cable. ( usually Tec ) and the three phase machine is operable. The same Phase converter supplies all the machines.

The PP will run more than one machine at a time. I assume it would likely run 3 or 4 machines, I've never tried it as I usually work alone.

Mine is now about 14 years old. I bought it new and its been really good. The downside is that its expensive. The upside is everything else. Its one of those cry once things.