Any help will be greatly appreciated. I have an MC-60 treadmill speed controller. I'm mounting the motor on a drill press. I put switch on the wipe terminal on the pot and added a reverse switch on the motor leads. I have it geared way down so that I can do some thread tapping. I'd like to have it start and stop immediately. I'm trying to eliminate the soft start and stop. Putting a switch from the board (red wire to the motor) gives me what I'm looking for but I am concerned about whether the board needs the load from the motor. Is it safe for the speed controller to run with a switch on the motor lead?
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MC-60 treadmill Speed control (controller needs a load ?)
- Thread starter DenJon
- Start date
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- Apr 30, 2015
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- 11,290
Hi DenJon- It's risky to interrupt the motor connections with power on; you could blow the output devices on the controller. As long as you do the switching with power off you'll be ok- but doing tapping might be awkward though
Mark
Mark
- Joined
- Sep 28, 2013
- Messages
- 4,306
if you want the motor to restart at the same speed then cut or remove the resistor labelled RPS3 - it is connected to one of the legs of the speed pot (center one I think).
No harm in using a fwd/rev switch to interrupt power to the motor, just make sure it has a center=off position between the two. If you're tapping, you'll be doing it slowly, so there shouldn't be any risk. I've been doing it for years on my drill press without issues. Just be aware that without a way to brake the motor or spindle, there'll be some spin down time so the tap will cut a few more threads before the motor stops. Keep a close eye on this, especially if you're tapping blind holes. I often start the tap under power, then finish off the last 1/3 or so by turning the spindle manually using the belts.
No harm in using a fwd/rev switch to interrupt power to the motor, just make sure it has a center=off position between the two. If you're tapping, you'll be doing it slowly, so there shouldn't be any risk. I've been doing it for years on my drill press without issues. Just be aware that without a way to brake the motor or spindle, there'll be some spin down time so the tap will cut a few more threads before the motor stops. Keep a close eye on this, especially if you're tapping blind holes. I often start the tap under power, then finish off the last 1/3 or so by turning the spindle manually using the belts.