PID loops to control Pumps

Hello Everyone,

I am a novice PLC programmer, this is going to be my first PLC program. I am using a Controllogix processor. I will be using the PIDE blocks to control the speed of some pumps. I will be implementing the logic (below), I just wanted some programmers to see if what I am doing is making things too complicated or if there are simpler ways of accomplishing this.

I will have the following four PID loops:

1. Tank Level
2. Discharge Pressure
3. Inlet pressure
4. Flow Rate.

I will then use the outputs of the above PID loops as Inputs to a Low Select Block. The output of the Low Select Block will be the Speed Signal to the pumps.

Essentialy, I wish to accomplish the following:

[font=&quot]The level control PID loop will maintain the selected tank level at its setpoint . The low suction pressure override PID loop will slow the shipping pumps down if their suction pressure is getting low. The high discharge pressure override PID loop will slow the shipping pumps down if their discharge pressure is getting too high. The high total crude flow override PID loop will slow the shipping pumps down if their flow rate gets too high .

Please let me know if I need to take into consideration any other factors or additional function blocks. Is what I am trying to do fairly typical in such type of application?

I apologize if this is too much of an open ended question. Look forward to hearing from you guys.
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the idea is good, however the I factor and the D factor makes it too complex and should be zero and only used for the tanklevel. If any override is active the I factor must be reset.