MC-60 Treadmill motor speed control: Can it be used as a variable DC power supply?

Thread Starter

Tonyr1084

Joined Sep 24, 2015
4,509
I have this MC-60 treadmill motor speed controller. Wondering if it can be used as a variable DC power supply. AC1 & AC2 (Blue & White) are the 120 VAC input. LG6 & LG7 are the DC output ranging from (I assume) zero volts all the way up to (probably not exceeding) 130 VDC. And yes, I know it's potentially dangerous. On the left hand side are "H" (LG3), "W" (LG4) and "L" (LG5), potentially the Red, White and Black wires that control the speed of the motor.

I'm not sure whether I should use a variable resistor (potentiometer) or a PWM input. H (Red) is the positive and L (Black) is the negative. The W is the variable feed that dictates the speed of the motor. This particular MC-60 came off of a treadmill that was digitally controlled. But it's not unlike the unit I have powering my band saw. Yes, I have an old treadmill motor powering my bandsaw. And it's variable speed is controlled via either a 5K or 10K ohm pot. I don't recall off hand, but I can vary the speed from quite low to pretty darn fast. So I'm wondering if I can use this as a variable power supply. OF COURSE I KNOW TO BE CAREFUL. I have no idea what kind of amperage it puts out but I KNOW it's enough to change my life permanently. So yes, I'll be darn darn darn careful messing with this. I'm just wondering if it can be used that way.IMG_5189.jpg
 

MaxHeadRoom

Joined Jul 18, 2013
20,658
It is a SCR bridge controller so the output is very similar to a Triac controller in nature.
It does not lend itself to a normal DC bench supply due to the high ripple content.
The terminals H,W,L are for 5k-10k pot control.
Max.
 

Thread Starter

Tonyr1084

Joined Sep 24, 2015
4,509
How bad is the ripple? Can it be filtered out with a substantial capacitor? I have a few I took out of some old scrapped stereo's rated 1500 µF @ 200 V. Think I have a few a little bigger as well. Would have to look around.

[edit] Have an 80µF 240 VAC cap
5 MFD @ 370 VAC

Even have 1.05µF @ 2100 VAC (micro wave oven cap)
 
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Thread Starter

Tonyr1084

Joined Sep 24, 2015
4,509
How about if I filter the output through a diode first? Then into a cap. Will that work? Will there need to be BEMF?
 
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