Page 1 of 2 12 LastLast
Results 1 to 15 of 18

Thread: 3 Phase Nirvana

  1. #1

    3 Phase Nirvana

    I recently acquired this Rotary Phase Converter. I’d been on the brink of buying a 20 hp American Rotary for some months now and was tempted by their recent sale. As soon as I thought I’d made up my mind, I stumbled across this converter on eBay offered for a BIN price of $900 but open to offers. Knowing what these cost new (~$2400), I expected my offer of $750 to be denied, but alas it was accepted and here we are. I had it shipped to me LTL freight via YRC for just over $150 (from Indiana to NC.) I was very happy with both the freight price and service. It weighs a little over 300# and is pretty compact for what it is.

    -Kay Industries 10 HP Phasemaster RPC
    -Manufactured in 2005 and used by a book company to run an industrial printer, apparently.

    The Kay machines are rated by the biggest motor they will start, so this will start a 10 HP motor, which is more comparable to an AR 15 or 20.

    This will enable me to power my 5 HP - 3 PH Tannewitz Model U table saw in my home shop as well as pull the trigger on one of the few 20-24” old iron 3 PH planers I’ve had a line on recently. I’ve powered an early 40s era Oliver 166BD 12” jointer with a VFD for the last few years and will likely keep it that way as I like the braking action on the cutterhead.

    Ive also been on the lookout for a nice sized 3 PH drill press, so this will open that door as well.

    Thanks to forum member David Kumm for his continuous advice on industrial grade machinery. He, along with a handful of others on this site, are wells of wisdom in this arena.

    Now I need to figure out how to wire this thing Trying to figure out if I’m just going to put in a few receptacles or source and wire up a 3 phase breaker panel, etc.

    Don’t worry, I’ll consult a licensed electrician before I do anything stupid. I’ll update this thread as things move along as a reference for anyone who may be considering this route in the future. After searching on a handful of different sites about RPCs, sizing them, wiring them, and using them, I wished there were more threads from folks who were new to 3 phase and their initiation into it.
    Attached Images Attached Images
    Last edited by Phillip Mitchell; 05-30-2020 at 6:30 AM.
    Still waters run deep.

  2. #2
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,878
    Keep an eye out for a three phase cyclone and big disk sander. Should be a a lot cheaper in three phase. Even with a rpc I recommend using as vfd to supply the drill press for the extra features.
    Bill D

  3. #3
    Quote Originally Posted by Bill Dufour View Post
    Keep an eye out for a three phase cyclone and big disk sander. Should be a a lot cheaper in three phase. Even with a rpc I recommend using as vfd to supply the drill press for the extra features.
    Bill D
    That’s a good point, Bill. 2 Hp and under VFDs are pretty cheap and a good option for the drill press.

    A cyclone is definitely on the list as I really need to upgrade my DC.
    Still waters run deep.

  4. #4
    Join Date
    Feb 2011
    Location
    Central WI
    Posts
    5,666
    Kay makes a good converter with a heavy motor. My first unit was that Kay. It is a little different than most in that it doesn't use a start capaciitor ( if I remember right, increasingly rare ). Be careful putting a three phase vfd on it though. The wild leg can exceed the voltage allowed by the vfd and blow it up. Don't ask how I know this. Best to check with the manufacturer after you verify the wild leg voltage.

    If you get into bigger motors, put the DC on a vfd rather than the RPC. Knowing the amp draw with various gates open and how much clean vs dirty filters affect the draw is helpful info. So it the ramp up and ability to speed or slow the impeller if needed. Dave

  5. #5
    I have that same unit. My planer is 7hp and used to run on a 7hp idler. The 10hp Kay turned it into a beast!

  6. #6
    Join Date
    Mar 2003
    Location
    SE PA - Central Bucks County
    Posts
    65,685
    That was a very nice buy! Personally, I'd go the panel route because it's cleanest and makes it easier over time as you adopt more and more "big iron" for your shop. It also mitigates insurance concerns should you ever have a disaster. I've always felt that "doing electrical correctly" is a good best practice. But that's me...others may disagree.
    --

    The most expensive tool is the one you buy "cheaply" and often...

  7. #7
    Join Date
    May 2014
    Location
    Alberta
    Posts
    2,162
    Phillip I installed a Roto phase phase converter about a year ago in my shop. Bought it used as well. I went the three phase panel route and found a panel used as well from my electrician. Breakers are far more expensive than single phase. I have a push button on/off switch on the wall near the two machines that I have that use three phase power currently. I went this route because the price for VFD's was quite high for the size of motors I needed to run ( 5h.p +). Works great and I am set up for any future 3 phase machines,my converter is 10h.p. maximun start and 30 h.p. combined running. All wired by my Electrician.

  8. #8
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,878
    For 3hp and under it is probably cheaper to buy a VFd then it is to buy the switchgear and disconnects required by code. A VfD qualifies as a disconenct per NEC.
    Bil lD

  9. #9
    Just a quick wiring question for those of you who may have this unit or other similar Kay units...

    I’m in the process of wiring and noticed that the Ground tab on the single phase input side was loose upon arrival. Loose as it not connected to or screw to anything at all on the tab end. There is a machine screw and tapped hole in the bottom right corner of the interior of the box that is 1 of 4 screws that hold this metal wiring panel on to the actual box. Can I / should I attach the ground tab to this point (as shown in the photo below) ? Based on the curvature and length of the ground wire, this appears to be where this goes, but I’m unsure.

    There are also (2) 18 Ga wires, on red and one black that are part of the current sensor that are hanging down with electrical tape on the ends and not connected to anything (also seen bottom right of photo) Does anyone know if this is stock / ok or do they need to be connected to something?

    I’ve searched online for stock photos of the wiring panel for Kay RPCs but am coming up empty for this particular info.

    If I don’t get a clear answer here, I will contact Kay to see what they have to say

    ——-

    Just to update - I am running 4 ga wire from an existing but empty 60 amp breaker in my 200 amp service panel in to the RPC. It’s about a 30’ run of wire. I’m using 4 ga because that’s what the Kay literature recommends and it will already be bought and in place should I decide to upsize the breaker for more running more amps simultaneously. My current / immediate future needs are a 5HP table saw and either a 7.5 or 9 HP planer.

    Based on the calculations that Kay recommends, this seems it should power up to 10 HP, but I would need to upsize the breaker if I wanted to run more continuous amps/HP than that, which I probably won’t for a while. I’m trying to get the converter simply wired with a single 30 amp receptacle with 8 ga wire on the output site initially just to make sure that things are working properly. Then I plan to search for a nice used 3 phase panel and run at least a couple different circuits from there.

    Thanks for any advice as always!
    Attached Images Attached Images
    Last edited by Phillip Mitchell; 06-04-2020 at 8:42 PM.
    Still waters run deep.

  10. #10
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,878
    You can attach the ground wire pretty much anywhere you want. Make sure it is electrically connected not just touching paint. Is that screw going into metal or a plastic clip of some kind. Use an ohm meter to verify.
    I bought a used welder and they had reversed ground and one hot lead. It was trying to run on 120 instead of 240 and the case was hot. It sat next to my laundry sink!
    Bil lD

  11. #11
    Quote Originally Posted by Bill Dufour View Post
    You can attach the ground wire pretty much anywhere you want. Make sure it is electrically connected not just touching paint. Is that screw going into metal or a plastic clip of some kind. Use an ohm meter to verify.
    I bought a used welder and they had reversed ground and one hot lead. It was trying to run on 120 instead of 240 and the case was hot. It sat next to my laundry sink!
    Bil lD
    Thanks Bill. I think the screw is going into a tapped metal hole, but will check later on. I have my electrician coming by later to hook up the wire at the single phase breaker connection and will have him look everything over before I give it juice. I’m comfortable with basic wiring (receptacles, switches, motors, etc) but am just not familiar enough with breaker panels to feel totally comfortable doing that myself, plus my electrician is basically my neighbor so it’s pretty easy to get him to come over for 15 minutes if I’ve done all the heavy lifting prior and all he has to do is give it a once over and hook up a breaker.
    Still waters run deep.

  12. #12
    I have the converter wired and had an electrician stop by yesterday to hook up to the single phase breaker panel.

    60 amp single phase breaker on the input side with 4 ga wire, then 8 ga wire on the output side to a L15-30 (30 amp) twist lock receptacle that will be for the 5 HP Tannewitz table saw. This is temporary wiring just to test the converter and make sure all is well with the unit. The 60 amp breaker was already in the panel and not being used and I didn’t want to have to wait on a mail order breaker to arrive...none of the electrical supply houses carry any Square D breakers and Lowe’s didn’t have anything over 50A on the shelf. I can for see upsizing the input breaker to 70 or 80 amps in the future, if I add in any bigger amp machines.

    We ran the converter (no load bc I don’t have the table saw in my shop currently) and it seemed to run smooth and sounded much quieter idling than I expected based on reading online about RPC idler motor noise. Standing right beside it, you could tell it was on but we were holding a normal conversation with no difficulty.

    The output voltage was 234-245 V depending on if the meter was touching the wild leg or not.

    The next step is to move the Tannewitz Model U in my shop and run it.

    In the meantime I will search for a reasonably priced, smaller amperage 3 phase breaker panel and breakers for a more permanent and flexible output arrangement. Anyone have any suggestions for an appropriately sized 3 phase panel for this size converter? The smallest I’m really seeing is 125A, which seems like way more than I could ever use as a sub panel. More like 60 amp max subpanel in my view, but what do I know?
    Attached Images Attached Images
    Still waters run deep.

  13. #13
    All you need is a MLO panel, smallest rated ones are for about 125a. Look for a used one with breakers.

  14. #14
    roto noise ive seen is from the thin steel cases that have all the electronic stuff. Mine was pretty quiet then made some noise and even tapping it on the cover made it quieter temp. Ill line it all when I have time. Reminds me of the flapping steel base on the General 8" jointer. Turn on the old SCM stuff and all you hear is the hum from the head and no lower cabinet noise.

  15. #15
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,878
    I have painted the unseen side of metal cabinets with grafting seal or latex base roofing seal. The rubber quiets any noise or vibration. Truck bed paint would work to.
    Bill D.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •