AB1500 PLC Averaging

Has anyone explored averaging inputs or outputs? I think a PID may be the way to go but I have little experience with them.

Thanks in advance,

Chris

Greetings xetrov123, and welcome aboard. You have dropped in on a great site for all things PLC, so bookmark it.

We had a thread yesterday about averaging in Logix500 PLCs, you might want to take a look and follow the search threads.
http://www.plctalk.net/qanda/showthread.php?t=40621

We can more helpful if we have more detail on what it is you are trying to accomplish.

We are replacing a pneumatic controller with an electric linear actuator on an oxygen production system. The actuator modulates a butterfly valve to maintain a certain product pressure. The volume of air flow changes as the system "pulses" from one tank to another.

We are using a 0 to 50 PSI sensor and the actuator uses a 4 to 20mA loop to control it. The actuator is a high accuracy type.

I am trying to develop a control scheme to control the pressure with the linear actuator.

I am thinking of using a PID loop but have little experience using one. The other option I thought of was averaging the input over a certain amount of time and using a SCP, changing the scale of the SCP and the amount of time I average to limit hunting.

To average a signal try using a FIFO table, for instance use a 1 second timer ton enter data to the table, the table must have 60 positions then you can sum all the data in the table then divide it by 60 and you have the average every minute, the use the average value with your SCP instruction.