DC Motor Control Panel

[arvidj]

Given that you are using a double pole double throw (DPDT) centre off switch to reverse the polarity to the motor (to enable forward and reverse), you need a DPDT momentary action switch for your jog. The reason for this is that you need to send both the positive and negative to the motor.

You would wire the switch so one side connects the positive power feed to the motor and the other connects the negative to the motor (both wired for forward rotation). As stated above, this allows both to function independently of each other. I drew up a quick schematic.

I think there may be a" interesting" issue with this diagram. If I am not mistaken, when you turn the motor on using the DPDT Center Off switch [move the connector to the "up" position in the box diagram" and then activate the DPTD Momentary switch – either on purpose or by accident – you create a short to the DC power supply. It only happens in one directional setting of the DPDT Center Off switch [the up position] – and in the other directional setting of the DPDT Center Off switch [the down position] the DPTD Momentary switch is simply in parallel so the action is benign.


Assuming it was a “from scratch” wiring job I would use a SPDT "On-Off-Momentary On" switch from the power supply for “Run – Off – Jog” and follow that up with a DPDT “On-On” switch to set the direction “Forward --Reverse”

But then again I may not have had enough coffee yet this morning and am not thinking straight.

Arvid

 

[Hawkeye]

Arvid, you hit the nail on the head. Your solution is the easiest way to prevent short circuits.

 

[Rbeckett]

Model MC-60 -Proform Fitness Products

Kelroy
Does the control board control voltage or Pulse width? I didnt see any provision for a speed control knob in the diagrams so I assume it is controlled prior to getting to the direction control switch (DPDT). I am trying to build a forward/reverse for a stepper motor with speed control and that is a critter of a completely different color. Thanks for the clarification.
Bob

 

[kelroy]

The board was originally down by the motor. I have since moved it up with the control panel. Yes it had a slider poteniometer and I changed it to a rotory type. The control panel has 3 tabs marked red,white and black on left side of panel. All I had to do was shorten the wires. I believe but am not sure it controls voltage. The choke transformer I believe would control pulse width.