Sartorius DCU 3, Руководство оператора

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Operators Handbook DCU3 – System
6., Main function „Control Loops“
BAEDCU3 - Rev. 4.6 - 0504 6 - 30
6.19 Pressure Controller
For control of the pressure inside a culture vessel the DCU system comprises a PID controller with
continuous output. The corresponding analogue output signal 0...20 mA of the DCU3 - system controls
a continuous control valve in the exhaust line via an I/P converter.
The pressure controller can operate as a servo controller in the pO
2
cascade control circuit.
6.19.1 Operating Display
For a description of the tags, the physical units or entries, the displayed value or function
and of the required inputs see the table in section
6.3, Controller Operation in General.
6.19.2 Special Notes
When the pressure controller is switched off, the control valve fully opens.
Depending on the flow rate adjusted at the fermentor, the pressure controller can only work
at pressure setpoints exceeding approx. 200 ... 400 mbar.