On/off control of a 24v12 board

I have a brush dc motor that controls a small conveyor. The conveyor’s motor should start turning at low speed when the start signal is turned on. The motor should shift up to high speed if the high speed signal is given and the coveyor should stop if the start signal and the high speed signal are off.

So my questions are:

  1. If the 24v12 board is configured for analog control and has a fixed resistor attached to the analog input, can I control the motor by turning Vin on and off?
  2. If I connect the analog input to a relay network that allows me to switch in resistors of different size, can I change speed while the motor is turning?

Thanks for your help.


As I said in my reply to the email you sent, if you want the motor to run at a set speed when the controller is receiving power, you can connect the S pin directly to either + or - and then set the Max. speed setting of the controller to your desired speed. You will probably also need to check the Ignore Pot Disconnect checkbox in the advanced settings tab.

However, controlling the SMC that way, you would not be able to change the speed by changing the resistance. A voltage divider circuit where you could switch between two resistors might work. How are you ultimately planning to control your system (e.g. manually with switches or from another device)?



I think I might have a problem related with this, I set a manual speed to the SMC with the bar of the software, but when I turn off the smc and then turn on again the SMC has been reset and the motor no longer moves. Is there a way to avoid the SMC to reset when I remove the power source.

I want the motor to move with an specific static speed every time I connect it to the power source.

Thank you!


No, our Simple Motor Controllers do not have any way to remember the last command sent to them when powered off. Once you have powered your Simple Motor Controller back on you, must send a new command to it.

Alternatively, if you just want the motor to stay at a static speed, you might be able to use a switch and a power source that outputs a voltage that results in the speed you want the motor go.