Pulse Driven Variable Power

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I have an application I'm trying to solve which would allow ... - May 14, 2010 by Tim Ryder

If you want to vary the voltage to control the motor speed, ... - May 29, 2010 by Vinit

Tim Ryder

#61830

Pulse Driven Variable Power | 14 May, 2010

I have an application I'm trying to solve which would allow me to vary voltage going to an Electric Solenoid at 24v ~3.0amps DC. What I want to do is create a device to vary the voltage going to the Solenoid using a pulsed digital input. I have a motor controller which has a High Speed output and it is programmable to me. I would like to somehow utilize this output to control this circuit to vary the voltage going to my solenoid.

I don't have MUCH experience with electronic pcb/circuit design so I need lay mens terms...

Anyone have any ideas how I can accomplish this? Again Steady power supply of 24vdc at 3.0a and I need to vary the output voltage from 0-24 based on digital pulsed input.

Thanks in advance!

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Vinit

#61967

Pulse Driven Variable Power | 29 May, 2010

If you want to vary the voltage to control the motor speed, then this is not the correct way. Though you can use LM317 for reducing the votage (using a 5K potentiometer) which will sure reduce the speed but it'll reduce the torque tremendously. For DC motors, you should vary the speed using PWM. This will enable you to change the speed depending on the Duty Cycle/Frequency of the pulse. You can use a 555 with suitable combination of R and C for this.

The output of 555 (PWM) will be fed to the gate of a Mosfet (such as P55N) to drive the motor. If you need help in circuit design, just mention the motor details.

Regards Vinit

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