ACM versus CM on Analog input

[rookieprogrammer]

I have a 24v V570 with a negative chassis ground. For my analog inputs on the v200 snap in, it shows 0-10v input using ACM as the common. Nothing is shown on the unitronics cut sheet that shows a connection from the "CM" connection.

Should I connect the "CM" to ground (negative)? Should I jumper ACM to CM to ground?

Thanks!

[Walkerok]

I noticed that you did not get an answer to your question. I am assuming that you have a V200-18-e3xb type snap in module given how you asked your question.

No, ACM and CM should not be jumpered. CM is to be used only if you are using a 100 Ohm PT temperature input as where you land the 3rd wire of your RTD input. ACM is to be used for analog input commons only (0-10Vdc, 0-20ma, 4-20ma). If you were to use thermocouple inputs then you would land those on the Input + and input - terminals on the E3XB.

Thanks

Keith

[rookieprogrammer]

Thanks. I had given up on Unitronics. I'm actually having quite the hard time getting support. I've got a PID problem no one can seem to help me with. Will try another post. Have spoken to you guys in MA, and I'm told there is a PID "guru" in Israel, but they won't get them involved. I'm running a PID that needs to output a PWM signal to a stepper. Got the program written by a veteran programmer, but I think this might be a little beyond his experience level.

[Emil]

Please contact me with e-mail to support@unitronics.com with some details of your application and the problem you face. I'll make my best to help you ASAP.

[Cara Bereck Levy]

Rookieprogrammer, Emil is the PID expert, so please do contact him.

I apologize for the inconvenience; unfortunately you posted during national holidays here...and I guess it got piled under the backlog.

I am sure Emil will get you up and running in short order.