Announcement

Collapse
No announcement yet.

Totally Off Topic..What is this DC Motor Part?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Totally Off Topic..What is this DC Motor Part?

    This is another "great buy" that I made, a very nice treadmill that ran for one day, then sporadically, now...Kaput! I checked the little LED's and know the drill there, but my question is...what is this coil looking part (see Cell Phone Camera picture below)? It buzzes like crazy when I try to get it going...which it will in little spurts...but only when it feels like it. the "wiring diagram" in the machine is a stylized schematic, so is of little help...plus it looks to be for a different model, anyways.
    The buzzing noise was there when it was working, as well.
    Then, I am wondering if I can "Rig" a speed control to that motor to totally bypass the need for the control board. I'd even be content to wire it for a given speed that matches my walking, with no variablity. I looked at Router Speed controls, but they are for AC Brush type motors, this is a 2.5 HP Permanent Magnet DC Motor.

    I solicit the advice and guidance here, because my fellow forum members are all- knowing and extremely intelligent!!!t I know how to buy anew controller board,,,but I'm curious what this coil is, and why it buzzes so loudly....
    Last edited by Hotfoot; 02-16-2008, 03:03 PM.
    "Good Enough Never Is"

  • #2
    Its a transformer. Read the sticker on the top and it will tell you the input/output along with the number of turns on the primary and secondary coils. The buzzing is one of the coils shorting out internally. And if the motor is a DC motor then you can't get rid of the control board, because it has the rectifier to convert the AC to DC. Just on general guess work I would say the the transformer takes 120 Vac in and puts out 12 or 14 Vac to the rectifier to convert to dc to run the motor. Motor speed can be controlled by DC voltage or current depending on the type used (this also should be on the motor case on a sticker or stamped).

    Comment


    • #3
      I could be wrong, but it looks like there are only 2 leads coming from that coil. If that's the case, it's not a transformer.

      Dave
      Still building my new old truck - see the progress!
      http://www.ford-trucks.com/forums/65...-coe-idea.html
      http://www.hobartwelders.com/weldtal...ad.php?t=27017

      Square Wave TIG 200 - Woot!
      MM180
      SP125+

      Comment


      • #4
        There are only two wires. Here is a closeup of the label...

        "Good Enough Never Is"

        Comment


        • #5
          Best guess is it's there to do the same thing the choke does on a welder - smooth out the current. It would keep the motor speed more constant when a person is walking or running on it, which would tend to make the motor speed up and slow down with each step.

          In my opinion, you could probably bypass it for testing purposes, just to see if the treadmill runs without it in the circuit. After all, it's just a piece of wire - wound a bunch of times around an iron core.

          Dave
          Still building my new old truck - see the progress!
          http://www.ford-trucks.com/forums/65...-coe-idea.html
          http://www.hobartwelders.com/weldtal...ad.php?t=27017

          Square Wave TIG 200 - Woot!
          MM180
          SP125+

          Comment


          • #6
            http://www.wikipatents.com/5367600.html

            Don't know if any of it'll make sense, but one of the things discussed here is the load regulation of treadmills.

            Dave
            Still building my new old truck - see the progress!
            http://www.ford-trucks.com/forums/65...-coe-idea.html
            http://www.hobartwelders.com/weldtal...ad.php?t=27017

            Square Wave TIG 200 - Woot!
            MM180
            SP125+

            Comment


            • #7
              Originally posted by whateg0 View Post
              Best guess is it's there to do the same thing the choke does on a welder - smooth out the current. It would keep the motor speed more constant when a person is walking or running on it, which would tend to make the motor speed up and slow down with each step.

              In my opinion, you could probably bypass it for testing purposes, just to see if the treadmill runs without it in the circuit. After all, it's just a piece of wire - wound a bunch of times around an iron core.

              Dave
              Its labeled in this diagram (if that's it) as a choke. I bypassed it straight from the lug on the board to the motor, and the motor would not do anything.
              "Good Enough Never Is"

              Comment


              • #8
                Okay, so back to basics...

                Is there voltage going to the motor? (at the terminals on the control bd.)

                Are there any markings on the motor that identify the operating voltage or current?

                Sorry, just saw the voltage below the motor in the diagram. What happens if you apply some voltage to the motor? Do you have a couple of 12V batteries laying around? Think of it as a wire feed motor on a MIG welder. More voltage goes faster. The difference is that this motor has an inductor in series with it to help even out the speed.


                Dave
                Last edited by whateg0; 02-16-2008, 07:32 PM.
                Still building my new old truck - see the progress!
                http://www.ford-trucks.com/forums/65...-coe-idea.html
                http://www.hobartwelders.com/weldtal...ad.php?t=27017

                Square Wave TIG 200 - Woot!
                MM180
                SP125+

                Comment


                • #9
                  Originally posted by whateg0 View Post
                  Okay, so back to basics...

                  Is there voltage going to the motor? (at the terminals on the control bd.)

                  Are there any markings on the motor that identify the operating voltage or current?

                  Sorry, just saw the voltage below the motor in the diagram. What happens if you apply some voltage to the motor? Do you have a couple of 12V batteries laying around? Think of it as a wire feed motor on a MIG welder. More voltage goes faster. The difference is that this motor has an inductor in series with it to help even out the speed.


                  Dave
                  Well, cheapie Voltmeter just crapped out on me, but here is the motor tag. I have another meter somewheres that I'll try to dig up.
                  "Good Enough Never Is"

                  Comment


                  • #10
                    I found out the problem

                    You see that last line that SAYS " MADE IN CHINA" Theres your problem, the little asian guy that built that motor for $3 a year forgot to do something and inadvertantly it broked.

                    Comment


                    • #11
                      Originally posted by 7mag_Jake View Post
                      You see that last line that SAYS " MADE IN CHINA" Theres your problem, the little asian guy that built that motor for $3 a year forgot to do something and inadvertantly it broked.
                      ???I don't see it The last line is the part #
                      "Good Enough Never Is"

                      Comment


                      • #12
                        Why not start backwards and see if voltage is present at the motor. If so it a good bet the motor is shot. Kinda rare for DC motos ut it does happen.

                        Comment


                        • #13
                          Yea before going and messing with any of the electronics, get your hands on a good digital meter and test to make sure voltage is going to the motor and is even.

                          The transformer looks to be wired as a choke in this circuit since there are only two wires and a ground, (the plate its mounted to).
                          Dave

                          Welcome to Sonic Orb Studios:
                          http://sonicorbstudios.squarespace.com/

                          Comment


                          • #14
                            Most likely component to go out would be the voltage controller chip then next likely would be one or more rectifier diodes. Isolate and check the rectifiers.

                            It's unlikely that the choke is bad but you could check that with an ohm meter. There should be continuity between the two leads and no continuity between either lead and case ground. As stated above, it's there to smooth out the DC current.

                            You have a 90VDC motor so you should have DC (probably pulsating DC) to the motor. Higher voltage for higher speed.

                            Oh...heck with it....just jog around the block.

                            Comment


                            • #15
                              Originally posted by TJJ View Post
                              Oh...heck with it....just jog around the block.
                              I imagine ol' Hotfoot gonna make him a creature wid dis Motor- not fer joggin'
                              Ed Conley
                              Screaming Broccoli, Inc
                              http://www.screamingbroccoli.net/
                              MM252
                              MM211
                              Miller Passport Plus, Spoolmate 100
                              TA185
                              SO 2020 Bender
                              Miller 125c Plasma
                              "Hold my beer while I try this!"

                              Comment

                              Working...
                              X