Results 1 to 9 of 9

Thread: DC Motor Control

  1. #1
    Registered
    Join Date
    Jun 2003
    Location
    U.S.A.
    Posts
    166
    Downloads
    0
    Uploads
    0

    DC Motor Control

    Hi all,
    I am looking for a circuit diagram for a DC motor speed control. I am trying to control a 120VDC Permanant Magnet motor, 2 HP at about 12 amps. I want to be able to use 120 VAC input and be able to control o to 120 VDC. Any ideas? Thanks Ron


  2. #2
    Community Moderator Al_The_Man's Avatar
    Join Date
    Dec 2003
    Location
    Canada
    Posts
    19112
    Downloads
    0
    Uploads
    0
    Ron, Does the motor have a tach? Because one option would be if you can pick up one of the Westamp A662 servo amps of off ebay, they used to be a regular item by a couple of sellers, they used to go for about $35.00 each and were good for up to 6hp 120vac input.
    They made good spindle amps for cheap.
    Al


  3. #3
    Registered
    Join Date
    Jun 2003
    Location
    U.S.A.
    Posts
    166
    Downloads
    0
    Uploads
    0
    Al,
    No tach on the motor. I have been looking on ebay. All the motor controllers I have seen so far that are 120 VAC input only go to 90 VDC output. Anything over 90VDC output require 230VAC input. I'm trying to avoid going to 230VAC input. Ron


  4. #4
    Gold Member Bloy2004's Avatar
    Join Date
    Oct 2003
    Location
    Sturgeon Bay, WI
    Posts
    925
    Downloads
    0
    Uploads
    0
    Try this item:
    http://www.surpluscenter.com/item.as...tname=electric

    I have two of these....one for the lathe, one for the mill spindle of a 3 in 1 machine( along with two 130 volt DC motors from same site). There is also a pot for variable control(extra) listed on the same page. I haven't hooked anything up yet but if the original AC motors begin to fail, I will begin retrofitting.
    Last edited by Bloy2004; 03-07-2004 at 09:08 PM.


  • #5
    Registered
    Join Date
    Jun 2003
    Location
    U.S.A.
    Posts
    166
    Downloads
    0
    Uploads
    0
    Bloy2004,
    Thanks for the link. I think one of those may just do the trick. Ron


  • #6
    Registered bunalmis's Avatar
    Join Date
    Jul 2003
    Location
    Turkey
    Posts
    246
    Downloads
    0
    Uploads
    0
    You can use light dimmer and bridge rectifier.
    (May be need small modifications.)


  • #7
    Registered
    Join Date
    Jun 2003
    Location
    U.S.A.
    Posts
    166
    Downloads
    0
    Uploads
    0
    bunalmis,
    I am looking at pulling a max of almost 12 amps. By using a light dimmer I think I would probably need to change the scr's to bigger ones to carry that much load, right? Do you have a diagram of a setup like this? Thanks Ron


  • #8
    ccm
    ccm is offline
    Registered
    Join Date
    Aug 2003
    Location
    Bridgewater, Ma
    Posts
    75
    Downloads
    0
    Uploads
    0
    I'm almost in the same boat, ac source but needed DC output...what I came up with .... I have an ac variac that I've put a bridge rectifier across the output along with a cap to clean it up alittle. I don't have the treadmill motor yet, but I've used the same rigging before and works pretty decent. The output I'm guessing is going to be around 125 to 135vdc @ approx. 15amps.

    my .02...

    art


  • #9
    Registered bunalmis's Avatar
    Join Date
    Jul 2003
    Location
    Turkey
    Posts
    246
    Downloads
    0
    Uploads
    0
    You can use 16A scr or triac for 12A aplications.
    Gate drive circuits dont need any modification.

    example links (i dind test this circuits)

    http://members.tripod.com/xexorz/sch...orquectrl.html
    (You can try this circuits)


    http://home.maine.rr.com/randylinscott/aug99.htm


    http://www.redhouse.force9.co.uk/dex...e/electr~1.htm
    (this circuit need rectifiers)


  • Posting Permissions



    About CNCzone.com

      We are the largest and most active discussion forum from DIY CNC Machines to the Cad/Cam software to run them. The site is 100% free to join and use, so join today!

    Follow us on

    Facebook Dribbble RSS Feed


    Search Engine Friendly URLs by vBSEO ©2011, Crawlability, Inc.