Hello all.
I have two questions about I project I am trying to complete.
I did a project in 2004 that contained my one and only PID with a micro 1500 from which I hoped to cut and paste the PID from. A PDF print out is attached.
1. I have a similar project using a micro 1200 # 1762-L24-BXB series C with a analog card # 1762-IF20F2 series A.
I copied the SCP and PID from the old program then pasted them into my new project. When I completed the new program and did verifiy, I got errors on all the values entered with decimal points in the SCP boxes requesting entegers only. I went ahead and changed the values to entegers. Then on re-verify warnings come up saying floating point OK only for 1500 and 1200 series C or better which I have.I can download the program and it seems to work. Why is the verify finding fault with the decimal point when the floating point math is OK for my PLC and "F" locations are available during programming?
2. With the PID worked out and controlling a valve, I will need to take over control at certain timed intervals and slowly ramp up from where valve is at (say 12 MA = 50% open for example) to max stroke (20 MA = 100% open). I'll then get a signal and slowly ramp back down to the original starting point and go back to direct PID control. My first guess is using a combination of a timer and counter and bumping output at set intervals. Any ideas?
I have two questions about I project I am trying to complete.
I did a project in 2004 that contained my one and only PID with a micro 1500 from which I hoped to cut and paste the PID from. A PDF print out is attached.
1. I have a similar project using a micro 1200 # 1762-L24-BXB series C with a analog card # 1762-IF20F2 series A.
I copied the SCP and PID from the old program then pasted them into my new project. When I completed the new program and did verifiy, I got errors on all the values entered with decimal points in the SCP boxes requesting entegers only. I went ahead and changed the values to entegers. Then on re-verify warnings come up saying floating point OK only for 1500 and 1200 series C or better which I have.I can download the program and it seems to work. Why is the verify finding fault with the decimal point when the floating point math is OK for my PLC and "F" locations are available during programming?
2. With the PID worked out and controlling a valve, I will need to take over control at certain timed intervals and slowly ramp up from where valve is at (say 12 MA = 50% open for example) to max stroke (20 MA = 100% open). I'll then get a signal and slowly ramp back down to the original starting point and go back to direct PID control. My first guess is using a combination of a timer and counter and bumping output at set intervals. Any ideas?