ascoldasice
Member
Hey,
I'm working on the automation of a reaction vessel and have a basic knowledge of siemens S7.
my problem is the next:
i'm dosing the polyol addition through a control valve. the polyol is captured in a reaction vessel. that vessel is on load cells.
So i have the analog value of the load cell as input and have an analog output of 4-10mA for controlling the control valve.
Now i wanna be able to say:
fill this vessel till it has 50 kg of polyol and then totally close the valve. I know it is possible with a P,PI or PID controller.
but how the hell do I begin on this? the vessel needs to be filled as fast and as accurate possible. But i can't have an overschoot because i cant get the polyol back out of the vessel.
could you please help me.
maybe a short example of a grafcet or program could be a hudge help for me...
tnx
Steven Vandermeulen
I'm working on the automation of a reaction vessel and have a basic knowledge of siemens S7.
my problem is the next:
i'm dosing the polyol addition through a control valve. the polyol is captured in a reaction vessel. that vessel is on load cells.
So i have the analog value of the load cell as input and have an analog output of 4-10mA for controlling the control valve.
Now i wanna be able to say:
fill this vessel till it has 50 kg of polyol and then totally close the valve. I know it is possible with a P,PI or PID controller.
but how the hell do I begin on this? the vessel needs to be filled as fast and as accurate possible. But i can't have an overschoot because i cant get the polyol back out of the vessel.
could you please help me.
maybe a short example of a grafcet or program could be a hudge help for me...
tnx
Steven Vandermeulen