584,842 active members*
4,551 visitors online*
Register for free
Login
IndustryArena Forum > CNC Electronics > Servo Motors / Drives > Help Figuring Out How Many Amps
Results 1 to 4 of 4
  1. #1
    Join Date
    Dec 2005
    Posts
    141

    Help Figuring Out How Many Amps

    Hi

    I am working on rebuilding a CNC mill and i am planning to reuse the servos that are installed.

    The X and Y are both the same and the plate lists them as 146V DC and lists pulse amps?? not sure what that is??

    The Z does not list a voltage, but seeing that it is using the same power source as the X and Y I assume it is also 146V and it lists a stall amperage as 23 amps.

    Now the million dollar question is, how many amps on average will those motors pull. how big of a power supply do i need to run them? Is there a formula to calculate that?

    At 140V, the largest power supply i can find is 6.6 amps, is that enough?


    Thanks in advanced
    Mike

    Pictures of both motor plates

    X&Y Motor

    Attachment 387146

    Z Motor

    Attachment 387144

  2. #2
    Join Date
    Dec 2013
    Posts
    5717

    Re: Help Figuring Out How Many Amps

    My mill has similar motors (Baldor), almost the same specification. I am running 2 of those, and a 6.3 amp stepper (z-axis) on one 75V, 5 amp power supply. I can do 200 IPM rapids, but normally limit it to 100 IPM.

    In actual operation, the motors draw only a fraction of their rated current.

    The other alternative is to find a 120/100 volt transformer and just build your own power supply. Just need a bridge rectifier, a couple of large capacitors rated for the voltage, and a 15K or so 5 watt bleeder resistor. That will give you about 141 volts.

    Something like this https://www.ebay.com/itm/Gomi-Electr....c100005.m1851
    Jim Dawson
    Sandy, Oregon, USA

  3. #3
    Join Date
    Jun 2010
    Posts
    4252

    Re: Help Figuring Out How Many Amps

    I too have DC servo motors on the axes. Under most conditions they would not draw more than 15 W each. To be sure, the motors could handle hundreds of watts, but they don't need to. 3:1 reduction motor to ball screw and 5 mm pitch ball screw.

    The spindle normally draws under 0.5 A at 150 VDC. More drag there. If it draws >2 A I reduce the feed rate. I did see it hit 8 A once when drilling Titanium: that was definitely a mistake!

    Cheers
    Roger

  4. #4
    Join Date
    Dec 2005
    Posts
    141

    Re: Help Figuring Out How Many Amps

    Thank you guys!!

Similar Threads

  1. Need help figuring out what I have
    By wrenchead in forum Want To Buy...Need help!
    Replies: 4
    Last Post: 08-05-2017, 04:08 AM
  2. Need help figuring out what I have.
    By autotec in forum DIY CNC Router Table Machines
    Replies: 10
    Last Post: 09-15-2012, 01:47 AM
  3. Need Help on Figuring Speeds
    By mgandy02 in forum DIY CNC Router Table Machines
    Replies: 0
    Last Post: 01-12-2007, 04:59 PM
  4. 2.5 amps per phase drive - 2.8 amps per phase bipolar motor ...
    By kochevnik in forum Stepper Motors / Drives
    Replies: 6
    Last Post: 10-23-2006, 04:48 AM
  5. Howto find input amps, from output amps on transformer?
    By sendkeys in forum CNC Machine Related Electronics
    Replies: 7
    Last Post: 07-15-2004, 01:13 AM

Tags for this Thread

Posting Permissions

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