B.3.2 Examples Of Control Loop Set-Up - GE Xcellerex XDUO Quad Single-Use Mode D'emploi

B User interface description
B.3 User interface: control functions

B.3.2 Examples of control loop set-up

B.3.2 Examples of control loop set-up
pH control
A pH control loop is always set up as primary controller in a cascade loop. The acid and
base PID control loops are nested loops inside the pH control loop. The output of the pH
PID control loop controls the setpoints of both inner loops (acid and base pump PID
control loops).
The following table explains some of the options available when configuring pH control.
When...
pH value increases
pH value decreases
The pH PID control loop is a split range loop, where controlled variable of each half of
the split range is zero at 50% output.
If the pH PID control loop is within the deadband range of the setpoint and calling for
neither the base nor acid, the output of the loop is 50%. A deviation from 50% output
will increase the setpoint of either the top half or the bottom half of the split range.
Vessel temperature control
Vessel temperature control is a stand-alone PID control loop. The controller is accessed
using Vessel Temperature faceplate. The vessel temperature control loop maintains the
temperature of the vessel at setpoint.
Agitator speed control
Agitator speed control is configured as a stand-alone loop for XDUO Quad Single-Use
Mixer.
The controller is accessed using Agitator faceplate. Agitator PID control loop maintains
the speed of the agitator at setpoint.
The following table describes agitator speed control modes.
392
Then...
base pump flow is decreased
or
acid pump flow is increased.
base pump flow is increased
or
acid pump flow is decreased.
Xcellerex XDUO Quad Single-Use Mixeur Mode d'emploi 29-0885-07 AA