Orn Jonsson
Member
Hi folks,
I have an application which needs some improvements....
Current app: An Auger type Filler with Servo and PLC controls is used to fill a container to a certain weight by adjusting the RPMs, and total Auger revolutions during a fill cycle.
Problem: The machine is controlling a distance (revs) to obtain a precise weight (indirect process variable). Wear and tear of the augers means a very frequent calibration of the machine.
Proposed solution: Build a new filler that fills to weight by measuring weight.
Problem: Do I need SERVO Control or Could I use a VFD Controlled motor and a PLC (don't mind complex programming), to control the speed during fill and the back off as I get closer to my tail adjusted setpoint?
I can't see using PID for this kind of control!!!!!!!! (unless. I moved the fill weight SP automatically up as I run the fill cycle, sort of a fill weight trajectory)
The material which is being used is very fine powder and I have to fill 400 grams +/- 5 grams in 20 seconds or less.
What is the key to not overshooting your fillweight when doing a very fast fill?
How do you deal with inconsistent tail weight?
Look forward to your replies
Orn Jonsson
I have an application which needs some improvements....
Current app: An Auger type Filler with Servo and PLC controls is used to fill a container to a certain weight by adjusting the RPMs, and total Auger revolutions during a fill cycle.
Problem: The machine is controlling a distance (revs) to obtain a precise weight (indirect process variable). Wear and tear of the augers means a very frequent calibration of the machine.
Proposed solution: Build a new filler that fills to weight by measuring weight.
Problem: Do I need SERVO Control or Could I use a VFD Controlled motor and a PLC (don't mind complex programming), to control the speed during fill and the back off as I get closer to my tail adjusted setpoint?
I can't see using PID for this kind of control!!!!!!!! (unless. I moved the fill weight SP automatically up as I run the fill cycle, sort of a fill weight trajectory)
The material which is being used is very fine powder and I have to fill 400 grams +/- 5 grams in 20 seconds or less.
What is the key to not overshooting your fillweight when doing a very fast fill?
How do you deal with inconsistent tail weight?
Look forward to your replies
Orn Jonsson