Potentiometer That Does Modbus RTU Via RS232 or RS485


Thread Starter

Newbie in need.

I am working with a click plc (C0-01DR-D) from automation direct. I need to interface with an internal timer but my model does not have any analog inputs. To get an analog input and keep the number of relay outputs I need is going to cost me another $90, so I am looking for a way to use a knob control without one. The tech from automation direct tells me the only way is to find a potentiometer (knob) that does Modbus RTU via RS232 or RS485. So far I have been unsuccessful in my search. if anyone knows of one I can buy, or a way to use a normal potentiometer with the tx/rx port, it would be greatly appreciated.
Thought about using two discrete inputs? Raise/lower a counter that is the timer set-point.

Set a limit to the ramp equivalent to the longest/shortest time you require.

I assume you can display a number

Start the count up/down by 1 then accelerate with time like a typical digital device set-point.
I'm pretty sure that if a pot with Modbus interface exists, it costs at least $90. I've actually never heard of such a thing. Though you could certainly make one out of Modbus remote I/O and a pot, but that doesn't gain you anything over replacing the Click. I thought they had analog expansion modules anyway?
I assume you have a way to display the timer settings?

You could simply use DI's and pushbuttons to increase and decrease the timer settings. Also to start, stop and reset.

You could also use a simple text based HMI with pushbuttons. It should be inexpensive.

good luck