Nick_SacmiUSA
Member
Hey All,
I am working on the programming to maintain level and pressure in a 80 gallon surge tank. This tank feeds fillers that fill either 2.5 Gallon or 5 Gallon bags. To maintain level, I have a modulating valve on the intake of the tank and to maintain pressure I have a nitrogen inlet valve and an exhaust valve. Previously, level was maintained with a simple, nonoptimized PID instruction and pressure would simply exhaust if it was above the setpoint deadband and and charge if it was below the setpoint deadband.
My thought is that I need a more advanced PID structure to maintain level, along with feed forward signals when we are filling a bag since each bag is such a large percentage of the tank level. To do this, I think I need one loop that is simply montioring the level in the tank and setting the modulating valve according to the SO (This PID would recieve the Feed Forward signal each time the filling sequence on our filler starts) and another PID that checks pressure in the tank since it can slow down our filling if it is higher and speed up our filling if it is lower.
Along with that, I want the pressure to be on a PID that switches between control actions (reverse and direct) to exhaust and charge the tank with nitrogen as necessary.
Does anyone have experience with a similar system? Any advice or code snippets to make the process easier? Am I stupid?
I am working on the programming to maintain level and pressure in a 80 gallon surge tank. This tank feeds fillers that fill either 2.5 Gallon or 5 Gallon bags. To maintain level, I have a modulating valve on the intake of the tank and to maintain pressure I have a nitrogen inlet valve and an exhaust valve. Previously, level was maintained with a simple, nonoptimized PID instruction and pressure would simply exhaust if it was above the setpoint deadband and and charge if it was below the setpoint deadband.
My thought is that I need a more advanced PID structure to maintain level, along with feed forward signals when we are filling a bag since each bag is such a large percentage of the tank level. To do this, I think I need one loop that is simply montioring the level in the tank and setting the modulating valve according to the SO (This PID would recieve the Feed Forward signal each time the filling sequence on our filler starts) and another PID that checks pressure in the tank since it can slow down our filling if it is higher and speed up our filling if it is lower.
Along with that, I want the pressure to be on a PID that switches between control actions (reverse and direct) to exhaust and charge the tank with nitrogen as necessary.
Does anyone have experience with a similar system? Any advice or code snippets to make the process easier? Am I stupid?