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I recently dismantled an old treadmill and removed the electric motor. I was wondering how I could power this and control it safely and preferably with a battery. There are three wires coming from it. A red one a black one and a green/yellow one. Pictures are below Motor specsMotor

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    \$\begingroup\$ You haven't actually asked a question so let me guess... Green/yellow is ground (see "The motor must be grounded"). Red and black are +ve and -ve. And its voltage rating for full power is on the label. \$\endgroup\$ – Brian Drummond Feb 12 '17 at 20:11
  • \$\begingroup\$ Ah, how I love "manufacturers" who can't even spell "Amps" right. Stock 0-90VDC PM motor - control the voltage to control the speed - will overheat at slow speeds if you don't provide a source of air that's not whatever built-in fan it has, and you should take the "treadmill power" with a grain of salt (more like 3/4-1 Hp in non-delusional units.) \$\endgroup\$ – Ecnerwal Feb 12 '17 at 20:16
  • \$\begingroup\$ @Ecnerwal, just out of curiosity, why don't you believe the nameplate data? You don't think it is really a 2.25 hp motor? \$\endgroup\$ – mkeith Feb 12 '17 at 21:55
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    \$\begingroup\$ I've used these and I've used honest-to-goodness industrial DC motors to drive similar things. On that basis, I think the Hp rating on treadmill motors is generally organic fertilizer. For one thing it would have to be just about 100% efficient merely based on amps x volts / 746 and I very much doubt it's anything over 80-85 at best. Could be much lower. \$\endgroup\$ – Ecnerwal Feb 13 '17 at 0:25
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    \$\begingroup\$ To the OP. If you want it to spin at full speed, you need to supply it with 90VDC. You can use a bunch of batteries in series to get up to 90VDC. If you want to spin it more slowly, you can use fewer batteries. If you want speed control, you need a DC motor controller. \$\endgroup\$ – mkeith Feb 13 '17 at 1:10
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The best way to power the motor is to use the electronic controller that would have been part of the treadmill. To power it with a battery, you could convert 12 volts DC to 120 volts AC with a power inverter rated 2000 watts. I am assuming the treadmill was powered by 120 volts because the motor requires 90 volts DC.

If the original controller is not available or doesn't work, you need to buy a DC motor controller in addition to an inverter. You could consider just rectifying the output of a power inverter, but that would not provide any limit on the starting current. The motor starting current would probably damage the inverter.

The "2.25 Hp" and "continuous duty motor." markings on the motor, need to be interpreted as two separate statements. The the 2.25 Hp rating is likely the "peak power rating" often found on consumer products. That rating can only be safely achieved only for a fraction of a second during acceleration. The motor can indeed operate continuously, but not at that power output.

The specifications also state (with corrected typo) "Amps 19 S6 25%." That means that the motor can operate continuously with a duty cycle of 25% of the time loaded and 75% of the time with no load. Unless otherwise specified, the time period for each cycle is 10 minutes. The 19 amps rather than the 2.25 Hp likely defines the loaded part of the duty cycle.

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Brian is correct, red (+) black (-) green (gnd) and to see the connections refer to this Youtube.

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