Hi everyone. Before I continue, let me just point out that I’ve never worked with motors before, and I’m not exactly the most informed guy out there when it comes to EE. Programming is my trade, so please excuse any obscenely stupid things I might say in relation to electronics :oops:
Anyways, a friend of mine was throwing an old JUGs pitching machine which he had for some reason and gave it to me since I said I could fix it. It has two giant 90v DC motors. These are the specs on the labels:
Model Number: SR3616-681-7
VOLTS: 90 DC
AMP: 3.0
HP: 1/4
RPM: 1900
DUTY: Spec
Field: PM
After some short Googling I found [this forum post someone made with pictures that look exactly like my model, in case that’s relevant.
I’ve tested the two motors and they both appear to work fine, however the circuit board whose job it is to regulate their speed doesn’t. Connecting it results in only one of the two motors actually spinning, and it spins at extremely high speeds.
What I’m trying to do is find out a way to regulate the speed on these things, because as it is the damn thing only pitches at 120+ mph(also those high speeds probably aren’t too good for the motor(s)). Ideally, I’d be able to hook it up to an arduino or something and have fun programming it to do whatever I want. Although I’d be fine with using what it already has for now: two big potentiometer thingys.
[Here is a pic of the front of the board, and [one of the back. The two gold cylinder things are potentiometers meant to regulate the speed of each motor, and the thing in the middle is a simple on/off switch.
There are some weird components there I’ve never seen before, such as that long brown rectangular thing, those two yellow rectangles on the top corners, and that clear plastic thing on the power cable.
I could attempt to repair the existing board, but coming up with my own solution is more fun and would let me do things like preset pitching styles, and maybe even laser targeting :D.
Here’s what I (think) I understand so far:
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I need to have a voltage regulator of some sort to control the speed of the motors. This thing’s circuit board has two LM723CN chips, which I assume fulfill that purpose.
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If I wanted to control it with an arduino, I’d need transistors or relays to control the supply of power (from an external source) to the motors.
What would you do in this situation? How could I control/regulate those two enormous motors with an itsy bitsy arduino?
Any help, advice, tutorials, or fingers pointing the right direction would be greatly appreciated!
Thanks in advance!](Imgur: The magic of the Internet)](Imgur: The magic of the Internet)](http://forum.gon.com/showthread.php?t=449958)