Sartorius DCU 3, Operator'S Handbook Manual

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Operators Handbook DCU3 – System
6., Main function „Control Loops“
BAEDCU3 - Rev. 4.6 - 0504 6 - 32
6.20.3 Special Notes
When errors occur during communication with the balance system (SIO01 I/O error....) the
controller output will remain at its last value. After elimination of the error the DCU3 - system
automatically requests the balance to continue with the communication.
Depending on the configuration of the system the calculation of the controller can take up to
20 s. Thus any inputs into the menu will also be processed within such a cycle.
The measurement ranges for the flow (entry „FLOW“) and for the weight measured by the
Sartorius balance system (entry „FWEIGH“) must be identical.
The delivery of the applied dosing pump considerably interferes with the controlled system.
Therefore the delivery of the pump must be adapted to the required flow.
For precise dosing the working range of the controller output „OUT“ must be within
15 ... 90 %. For this the delivery of the pump can be preselected by use of a tubing of the
appropriate size or a pump head with an appropriate membrane, which can deliver within
the intended delivery range.
6.20.4 Precision of Dosing Control
The precision of the dosing control depends on the following factors :
Resolution and precision of the balance system
Delivery of the pump
Flow rates
Environmental conditions (stable and interference-free support of the balance system
The accuracy given below for the FLOW-controller has been evaluated using a balance system type
MC1 - LC 6200, by Sartorius, Fed. Rep. of Germany and a dosing pump FE 211 by Sartorius BBI Sys-
tems GmbH. The working range of the balance system was 0 ... 6,200 g at a resolution of 0.1 g. The
pump was equipped with pump head type „F: 0.1“ and „F: 1“.
Sartorius- balance
type, resolution: [g] FE211 with pump head
[factor F] flow
[g/h] accurace
[g/h], [g/day], [g/week]
LC/IC, 0,1 g 0.1 50 .. 500 +/-1g, +/-2g, +/-5g
1 500 .. 5000 +/-2g, +/-3g, +/-5g
LC/IC, 1 g 0.1 50 .. 500 +/-3g, +/-5g, +/-10g
1 500 .. 5000 +/-5g, +/-8g, +/-10g