Page 1 of 2 12 LastLast
Results 1 to 15 of 22

Thread: VFD for single to three phase

  1. #1

    VFD for single to three phase

    I'm picking up a 8in General jointer tomorrow that has a 3 phase motor. Any thoughts on VFD inverters? When I lived in Minnesota all my machines where 3 phase and I built a rotary phase converter, It worked well but my electrician friend said the VFD was the way to go.

    Or should I just change the motor to single phase?

    Thanks
    Tim
    Last edited by Tim Cardinal; 04-04-2019 at 2:22 PM.

  2. #2
    Join Date
    Dec 2006
    Location
    Toronto Ontario
    Posts
    11,247
    Hi Tim, a jointer won't benefit from the variable speed and braking that a VFD will allow, however it's probably less expensive than purchasing a single phase motor and starter for the jointer.

    I would go with the VFD if the cost is reasonable............Rod.

  3. #3
    Quote Originally Posted by Rod Sheridan View Post
    Hi Tim, a jointer won't benefit from the variable speed and braking that a VFD will allow, however it's probably less expensive than purchasing a single phase motor and starter for the jointer.

    I would go with the VFD if the cost is reasonable............Rod.
    Amazon has a .75KW inverter for $100 Canadian sounds too good to be true..

  4. #4
    Join Date
    Feb 2011
    Location
    Central WI
    Posts
    5,666
    Use the existing RPC. No benefit to paying for a vfd in that application. The belt drive head will slow on its own and a vfd needs an additional brake resistor to quickly stop a head. Dave

  5. #5
    Quote Originally Posted by David Kumm View Post
    Use the existing RPC. No benefit to paying for a vfd in that application. The belt drive head will slow on its own and a vfd needs an additional brake resistor to quickly stop a head. Dave
    I don't have the RPC anymore, Sold it with my machines when we left Minnesota..

  6. #6
    Join Date
    Feb 2011
    Location
    Central WI
    Posts
    5,666
    Then a vfd should be under $200. If jointer has a manual starter, you can just plug the vfd into the machine and leave the starter closed- but don't ever use it to stop the machine, only the vfd controls. If a mag starter, you need to bypass it and wire directly to the motor. I put a switch on the single phase side before the recepticle so I can cut power to the vfd when not using the machine. Dave

  7. #7
    Quote Originally Posted by David Kumm View Post
    Then a vfd should be under $200. If jointer has a manual starter, you can just plug the vfd into the machine and leave the starter closed- but don't ever use it to stop the machine, only the vfd controls. If a mag starter, you need to bypass it and wire directly to the motor. I put a switch on the single phase side before the recepticle so I can cut power to the vfd when not using the machine. Dave
    Thanks Dave..

  8. #8
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,876
    On my lathe I mounted the VFD inside the headstock end pedestal and used the existing switches to control the VFD.
    On many cheap VFDs the cooling fan runs constantly. I added an extra contactor in front of the vfd so I can turn it off when I am done with the the lathe. I only turn it off after the spindle stops spinning.
    Bill D

  9. #9
    Quote Originally Posted by Bill Dufour View Post
    On my lathe I mounted the VFD inside the headstock end pedestal and used the existing switches to control the VFD.
    On many cheap VFDs the cooling fan runs constantly. I added an extra contactor in front of the vfd so I can turn it off when I am done with the the lathe. I only turn it off after the spindle stops spinning.
    Bill D
    Thanks Bill...I will see what i am dealing with tomorrow

  10. #10
    Do not get the HunwanYang or however your spell it, VFD. Mine was the 5hp model and worked a little then one day popped. Hard to sort through the manual too. Get a decent brand with a warranty.

  11. #11
    I just bought a TECO Westinghouse L510 from Wolf Automation for $138. It was pretty straight forward to wire up after watching a couple you tube videos. The basic setup is pretty straight forward but the dozens of possible options can get kind of overwhelming. They are pretty cool toys and definitely have more functions than you need for a jointer. Depending on if you can scrounge up the wire, enclosure and other pieces, you may end up closer to $200 getting the VFD set up.

    If you can find a good cheap used single phase replacement that’s probably the lowest cost option. If you can’t then the VFD is the winner, unless there might be more three phase equipment in your future. Then you are back to setting up a rotary phase converter.
    Last edited by Dan Jansen; 04-04-2019 at 10:13 PM.

  12. #12
    Quote Originally Posted by Dan Jansen View Post
    I just bought a TECO L510 from Wold Automation for $138. It was pretty straight forward to wire up after watching a couple you tube videos. The basic setup is pretty straight forward but the dozens of possible options can get kind of overwhelming. They are pretty cool toys and definitely have more functions than you need for a jointer. Depending on if you can scrounge up the wire, enclosure and other pieces, you may end up closer to $200 getting the VFD set up.

    If you can find a good cheap used single phase replacement that’s probably the lowest cost option. If you can’t then the VFD is the winner, unless there might be more three phase equipment in your future. Then you are back to setting up a rotary phase converter.
    The seller said he has some motors from years gone by..Ill have a look tomorrow for something single phase...my saw is only 1 1/2HP so if i find a 3 hp I'll be laughing..but if not ill probably do an inverter..

  13. #13
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,876
    Consider moving the 3phase motor to a drillpress or sander where variable speed and fast stop/reversing might be worth an inverter. Then buy a single phase for the jointer. The only advantage of a 3ph on a jointer is slow start if your wiring is on the small side.
    If you do convert the jointer to single phase you will have to replace two heater coils in the starter overloads. that is if it has a overload setup. Three phase it probably does have a starter and overloads.
    Bil lD.
    Last edited by Bill Dufour; 04-05-2019 at 12:44 AM.

  14. #14
    Join Date
    Jul 2013
    Posts
    547
    Blog Entries
    1
    Jack Forsberg sells very nice and suitable VFDs. His support is impeccable as well.

  15. #15
    Join Date
    Nov 2009
    Location
    Peoria, IL
    Posts
    4,443
    If you are comfortable with electronic equipment, then a cheap VFD may work. But there is programming and possibly remote switching to be done. The benefit of actually buying for a dealer is that you can get technical help. Something you definitely DON'T get with a $100 Amazon special.

Posting Permissions

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