plcplcplc1
Member
Hello everyone,
I need to control a discharge pressure in our pipeline and there's two ways of doing this:
1. By controlling the speed of the pump (RPM)
2. By controlling the position of a recirculation actuator (4-20 mA)
At the beginning I was using the PI Function Block to control the Pressure (PV) by modifying the Pump Speed (CV). But the problem is, sometimes the pump runs at its minimum capacity which is 2500 rpm (Low Limit) and the Pressure is still higher than what we want.
At this point is when we need to open the recirculation actuator to a fixed position (Manually) to allow the pump to run faster and still meet the desired discharge pressure.
Tech note 54859 mentions the following: "Coordinated Control (CC) – Controls a single process variable by manipulating as many as three different outputs."
I found a manual explaining this function:
http://integrated.cc/cse/ControlLog...Control Instructions - Continuous Process.pdf
My doubt is, when performing the Auto Tune function, is the CV going to variate the pump speed to its maximum capacity? Same with the actuator?
This is my first time using it, have anyone of you had used it before? Any recommendations or things I need to consider?
Thank you for your time.
PLC = 1769-L33ER Compact Logix 5370
I need to control a discharge pressure in our pipeline and there's two ways of doing this:
1. By controlling the speed of the pump (RPM)
2. By controlling the position of a recirculation actuator (4-20 mA)
At the beginning I was using the PI Function Block to control the Pressure (PV) by modifying the Pump Speed (CV). But the problem is, sometimes the pump runs at its minimum capacity which is 2500 rpm (Low Limit) and the Pressure is still higher than what we want.
At this point is when we need to open the recirculation actuator to a fixed position (Manually) to allow the pump to run faster and still meet the desired discharge pressure.
Tech note 54859 mentions the following: "Coordinated Control (CC) – Controls a single process variable by manipulating as many as three different outputs."
I found a manual explaining this function:
http://integrated.cc/cse/ControlLog...Control Instructions - Continuous Process.pdf
My doubt is, when performing the Auto Tune function, is the CV going to variate the pump speed to its maximum capacity? Same with the actuator?
This is my first time using it, have anyone of you had used it before? Any recommendations or things I need to consider?
Thank you for your time.
PLC = 1769-L33ER Compact Logix 5370