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Unread 03-05-2012, 17:13
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Re: Non-FRC Motor Controller?

Quote:
Originally Posted by rbmj View Post
I was looking for a couple of motor controllers for some personal projects of mine
Step 1 is to identify the current draw of the motors you want to control. Figure 3 to 6 Amps for small motors, smaller than what you'd see in FIRST.
Second decide on a voltage. Much of the world is 12 volts, because of the automotive industry. Most motor controllers you will find handle a wide range of voltages.
Then pick a motor controller that handles the current and voltage you want, has the control inputs you plan to use (e.g., PWM), and fits your budget.

Pulsing a relay, whether electromechanical or solid=state, is not a good practice.

The EM relay's contact will last only a few hours (they do wear), the maximum switching speed is single-digits per second (poor control resolution), and since you will have a hard time controlling the on-off time (duty cycle) the motor will be hard to control other than on and off.

Solid state doesn't have the contact wear, but the other issues remain valid.

The bottom line is, if you want to control a motor, use a motor controller.

You CAN build your own motor controller for under $20, but given your level of experience perhaps you should wait on that.

So, go find some motors....
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