Sartorius DCU 3, Operator'S Handbook Manual

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Operators Handbook DCU3 – System
5., Main Function „Calibration“
BAEDCU3 - Rev. 4.6 - 0504 5 - 10
5.7 Calibration of a Balance System
The fermentor weight (the „vessel content“) can be measured by balance platforms or load cells (i.e.
optional accessories). They will be connected to the DCU3 via a strain gauge measuring amplifier.
The measurement amplifier is scaled to a gross weight output signal. The gross weight comprises the
empty vessel with the drive system, the individual vessel equipment and the vessel content (medium).
„Zero-taring“ using the calibration function is done by measuring the weight of the completely
equipped culture vessel
without the culture medium and setting this weight as the „net weight“. How-
ever, tare correction is possible after changing the equipment of the culture vessel during a running
process. For this the net weight is stored and the tare weight will be adapted to the changing gross
weight.
5.7.1 Operating Display
Tag Entry Displayed value or function, required input
WEIGV kg display of net weight (WEIGH = GROSS - TARE)
GROSS kg display of gross weight
TARE kg display of tare weight
Start Taring Enabling the taring function
Start Hold Enabling the „hold“ function
PV ALARM Enabling the alarm display
CLOOP Selection of the controller menu
5.7.2 Calibration
1. For zero taring with the culture vessel being fully equipped, but without culture medium, start
the calibration with „Start taring“. Follow the instruction shown in the calibration menu.
2. If the culture vessel equipment is changed during the process, you can recalibrate the tar-
ing. Start the „Hold“ function for this and follow the instructions in the menü.