Page 3 of 7 FirstFirst 1234567 LastLast
Results 31 to 45 of 96
  1. #31
    BobL is offline Member: Blue and white apron brigade
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    7,182

    Default

    Quote Originally Posted by .RC. View Post
    Yes it is a 4KW version. I hooked it up to the 10EE and runs the MG fine off a 10amp power point .

    The unit indicates at idle the MG draws 1.8A, which I suspect is per phase on the three phase side. Running the lathe no load at 2500rpm it goes up to 6amps.

    These units if reliable and long lasting are bits of game changers for your older machinery with just a single motor to run everything.
    ,

    VFDs usually show per phase current so x sqrt(3) to get total current.
    That means 6A per phase = 10.49A total
    But are those currents @240V or 415V?
    If its at 415V you are going to be well over the 10A/240V limit.

  2. #32
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    I just put a clamp meter on mine.
    240v input was 3.9A, the VFD was showing 2.7A

    I tried putting the meter on the motor side, but it was showing 10A - obviously not right. It’s only a cheap meter so I’m picking it’s struggling with the VFD output waveform. I had the same issue originally when I tried to measure the voltage with the same meter and had to resort to my analogue meter.

    Steve

  3. #33
    BobL is offline Member: Blue and white apron brigade
    Join Date
    Feb 2006
    Location
    Perth
    Posts
    7,182

    Default

    Quote Originally Posted by OxxAndBert View Post
    I just put a clamp meter on mine.
    240v input was 3.9A, the VFD was showing 2.7A
    To compare those two you need to multiply the 2.7 by SQRT 3 so then it comes to 4.7A?
    Unless those VFD display amps are @415V

    I tried putting the meter on the motor side, but it was showing 10A - obviously not right. It’s only a cheap meter so I’m picking it’s struggling with the VFD output waveform. I had the same issue originally when I tried to measure the voltage with the same meter and had to resort to my analogue meter.
    Steve
    Yeah could be the meter but maybe not the wave form - more likely from the VFD noise.

    I did a bunch of simultaneous current measurements on a VFD powered compressor motor during compressor recharge cycles between 10 and 16A.
    I compared the VFD input and output currents using Fluke current clamps and they all agreed within 10% (most within 2%) but few of these measurements came close to the VFD display.
    The VFD display currents were usually a lot less than the inout and output currents.

  4. #34
    Join Date
    Nov 2007
    Location
    Near Rockhampton
    Posts
    270

    Default

    Quote Originally Posted by .RC. View Post

    I wonder if the big capacitors are the main components in the increased voltage.
    I presume these drives have a voltage doubling circuit as the input rectifier. This does place heavy stress on the filter capacitors, requiring more to share the load.

  5. #35
    Join Date
    Aug 2004
    Location
    Perth Western Australia
    Age
    65
    Posts
    203

    Default Earth connection

    I have wired my 2.2 kw ecogoo inverter to a 3 phase motor, however I don't know where to connect the motor's earth wire.
    There is no earth terminal with the motor connections, and I can't see any reference to a earth terminal in the manual.
    Do I run it to the 240v earth connection? or perhaps a mounting screw on the heatsink?

    Mark
    I've become a tool of my tools.

  6. #36
    Join Date
    Sep 2012
    Location
    York, North Yorkshire UK
    Posts
    6,436

    Default

    Hello Mark,

    Normally the motor, indeed any of the machine metalwork would be earthed to the input mains earth. To be sure I would use a test bulb, not a multimeter, to check that there was not any residual mains voltage on the motor case/frame to earth. I wouldn't use the heatsink screws on the VFD unless there was a specified earth point, and it should be marked as such anyway.
    Best Regards:
    Baron J.

  7. #37
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    I’ve run my motor earth to the earth terminal on the 240v/input side.
    Would have been nice if there was an earth terminal near the motor ones, but I guess that’s part of the cost compromise

    Steve

  8. #38
    Join Date
    Aug 2010
    Location
    Toorloo Arm, VIC
    Age
    39
    Posts
    1,270

    Default

    Quote Originally Posted by OxxAndBert View Post
    I’ve run my motor earth to the earth terminal on the 240v/input side.
    Would have been nice if there was an earth terminal near the motor ones, but I guess that’s part of the cost compromise

    Steve
    I've discovered that on a 4kw version you don't appear to get any earth terminal at all... Pretty ordinary. Not sure if RCs is the same. Currently on my temporary hookup the earths (motor and 240v input) are attached to the heatsink at the back - not really sure that's actually connected to... anything of use inside the unit, but given it's the only conductive part of the unit you can touch, I guess it fulfills the fault protection requirement.

    Running just the headstock, clutch disengaged settles in at about 3.6A on the 240v line, throwing the clutch spikes to 8A as the spindle starts up then drops back to about 6A. I'm sure that will increase a bit once it's got a chuck on and is running the quick change box as well. Rated (3.7kw) motor current is 6.8A per phase at 440v - not actually sure whether the VFD is putting that voltage out or not, but I did set that in the motor parameters. If it's not I think it worked out about 7.2A at 415V. I'm running mine off a 15A outlet, but wouldn't be surprised if under full load it'll draw more than that.

    Oh yeah, and with a 7.5sec ramp time, the current draw starts about 1.2A, slowly runs up to 4A when the motor reaches full speed, holds that for a couple of seconds, then drops back to 3.6A. Could probably run a much shorter ramp time and still not get much of an inrush spike, but given I have a clutch, I don't care much.

  9. #39
    Join Date
    Sep 2008
    Location
    Riddells Creek, Vic.
    Posts
    831

    Default Vector Control Mode.

    There are 2 option for Vector control- 0: - Vector Control without PG or 4: - Vector Control with PG, but I can't find any reference to what PG actually stands for in the instructions. Is any one using Vector Control?

  10. #40
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    From playing with other brands, I’m pretty sure the PG is when you have speed encoder on the motor for feedback.
    I’m not using vector control on my ones at this stage.

    Steve

  11. #41
    Join Date
    Jan 2012
    Location
    Melbourne
    Posts
    149

    Default

    PG = pulse generator (encoder)

  12. #42
    Join Date
    Sep 2008
    Location
    Riddells Creek, Vic.
    Posts
    831

    Default

    I tried Vector Control Mode but the motor did not like it, there must be more to it than just enabling VCM.

  13. #43
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    Did you do an auto tune?
    If so was it done before or after setting vector control?

    Steve

  14. #44
    Join Date
    Sep 2008
    Location
    Riddells Creek, Vic.
    Posts
    831

    Default

    Yes Steve I did do an Auto Tune before setting up Vector mode not after but it works perfectly in V/Hz mode so I will just leave it there.

  15. #45
    Join Date
    Nov 2017
    Location
    Geelong, Australia
    Age
    57
    Posts
    2,651

    Default

    Thanks. I was wondering if one needed to be done again after the vector mode was set.
    No idea whether that’s the case, but if you HAD done one then it would have ruled it out.

    Steve

Page 3 of 7 FirstFirst 1234567 LastLast

Similar Threads

  1. Any experiences with H&F granite surface plate ?
    By StrayAlien in forum METALWORK GENERAL
    Replies: 20
    Last Post: 5th Nov 2020, 08:59 PM
  2. Experiences About Frost Brand tools.T
    By familyguy in forum METALWORK GENERAL
    Replies: 17
    Last Post: 5th Aug 2018, 01:30 PM
  3. Replies: 10
    Last Post: 1st Jan 2018, 11:10 PM
  4. 240v to 220v cheap solution? For china stuff
    By j3dprints in forum ELECTRICALS
    Replies: 10
    Last Post: 21st Dec 2017, 11:41 PM
  5. Small Lathe Experiences
    By Blu_Rock in forum METALWORK GENERAL
    Replies: 48
    Last Post: 11th Nov 2008, 10:29 PM

Posting Permissions

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