sanyc Posted May 7, 2020 Report Share Posted May 7, 2020 Hi, First time I am using PID on a Jazz. I want to keep the pressure within a system steady, regulated by a solenoid valve that has a constant pressure supply on it; and in turn feeds the closed system. Attached are my setup and I have a few questions: 1. My CV is the controlled digital output on the solenoid valve that opens when the pressure drops; reads of a 0-10V pressure sensor; and closes when that pressure reaches my setpoint. How can I setup the CV to a digital output? 2. My Process Value and Setpoint I have them linked to the same MI because I want to keep the pressure at whatever pressure the pressure sensor reads from the beginning. Is that correct to do? 3. I cant seem to make it to operate the solenoid valve because I don't understand what the Control Value MI should be in order to simulate a digital output. I also set its range 0 and 1 but it needs further processing Thanks Quote Link to comment Share on other sites More sharing options...
MVP 2022 Joe Tauser Posted May 7, 2020 MVP 2022 Report Share Posted May 7, 2020 You change the value in the CV output to a digital output using PWM. Check the Help on that and then post your program with any questions. Also, look at the Help on "power-up". You can set the value of and MI when the PLC powers up - you don't need all those Store blocks. Joe T. Quote Link to comment Share on other sites More sharing options...
sanyc Posted May 8, 2020 Author Report Share Posted May 8, 2020 Thanks Joe for the input. So I set up the PWM Output as follows and set my numbers to the SI for the PID. As it is set up now once it reads a pressure drop of less than 30 it uses that number as a setpoint. Something does not trigger the PWM output Quote Link to comment Share on other sites More sharing options...
MVP 2022 Joe Tauser Posted May 8, 2020 MVP 2022 Report Share Posted May 8, 2020 19 hours ago, Joe Tauser said: post your program with any questions. By this I mean upload your program with your post so we can see the whole thing. Joe T. Quote Link to comment Share on other sites More sharing options...
sanyc Posted May 8, 2020 Author Report Share Posted May 8, 2020 Hi Joe, I dropped the PID in favor to on/off control. Turned out to be much simpler in my application. Also I figured out how to trigger the PWM output with 100% of the cycle time. Thanks for the help Quote Link to comment Share on other sites More sharing options...
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