Posted 27 Sep 2016 Does anyone have a good means of temperature control using Logix5000 PIDE instruction to control a SSR? Share this post Link to post Share on other sites
Posted 3 Oct 2016 Sorry that this got left out here so long. I believe there is a function block to do that but I have not used it. In the past I have taken the output from a PID block and turned on the SSR for a predetermined time period depending on the output of the PID. Simple enough to do with two timers. One timer is your period time and the other is the on time. You determine your maximum period between evaluations and set your period timer to that value. Lets say we pick 10 seconds. Every ten seconds we look at our PID output to see what percent on we are going to require. If our PID CV is set at 30%, then we set our On timer to 3 seconds (30% of our full period) and start timing. Our SSR is on during the 3 second On time and off for the remainder of the period - in our example 7 seconds or the remainder of the 10 second period. Share this post Link to post Share on other sites
