We have a machine we're trying to commission. It's a web converting machine. It takes webs of foil, wicking paper & a label and creates a chemical test strip that is used to ensure complete steam sterilization of medical equipment.
It has a series of rollers which either add a feature to the foil (for instance, a dimple in the foil in to which we squirt the chemical) or perform a function like slitting the webs into 6 individual strips or cutting to length at the end.
Anyway, that's the background. We're using the gearing function of the servo drives to adjust the speed of all the rollers relative to the feed roller to enable us to hold or adjust registration between the foil and the label layers. We've proved it works manually, now we're trying to get it to work automatically, under PID control. The PLC is an AB CompactLogix 1769-L33ER and I'm using RSLogix 5000 v20. The servos are Emerson Epsilon EP-Ps.
At the moment, I'm getting a ...CTL.SPOR (setpoint out of range error) and can't see why. I'm getting no output from the PID. The PID instruction is displaying the PV as 0.0 even though the process variable tag (LABEL_WINDOW_POS) is reading 33000.
I have it running in a scheduled task, every 1000ms. Can you take a look at the screen shots and see what I'm doing wrong, please?
It has a series of rollers which either add a feature to the foil (for instance, a dimple in the foil in to which we squirt the chemical) or perform a function like slitting the webs into 6 individual strips or cutting to length at the end.
Anyway, that's the background. We're using the gearing function of the servo drives to adjust the speed of all the rollers relative to the feed roller to enable us to hold or adjust registration between the foil and the label layers. We've proved it works manually, now we're trying to get it to work automatically, under PID control. The PLC is an AB CompactLogix 1769-L33ER and I'm using RSLogix 5000 v20. The servos are Emerson Epsilon EP-Ps.
At the moment, I'm getting a ...CTL.SPOR (setpoint out of range error) and can't see why. I'm getting no output from the PID. The PID instruction is displaying the PV as 0.0 even though the process variable tag (LABEL_WINDOW_POS) is reading 33000.
I have it running in a scheduled task, every 1000ms. Can you take a look at the screen shots and see what I'm doing wrong, please?
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