Sartorius DCU 3 Operator's Handbook Manual

Operators Handbook

BAEDCU3 - Rev. 4.6 - 0504

D C U 3 - S y s t e m

Digital Measurement and Control System for Fermentors

Operators Handbook DCU3 – System

Introduction

BAEDCU3 - Rev. 4.6 - 0504

Introduction

Sartorius BBI Systems´ digital measurement and control system for fermentors, the DCU3 – system, is
available as stand-alone unit for operation of Sartorius BBI Systems´ laboratory scale fermentors and
as a rack version for the measurement and control cabinets of pilot plant fermentors. All information
given in the handbook refer to the operation of these fermentors, unless otherwise specified. Above
this the DCU3-system can be applied as universal measurement and control system for fermentor
automation and for customized general measurement and control tasks.

This „Operator's Handbook“ describes all standard functions available with the software version 4.6 of
the DCU3 - system. In general the range of functions implemented for a specific fermentor is smaller
than the range that this manual describes. The DCU system can be adapted to the different fermentor
types by means of the software configuration and fermentor specific features.

 Besides the standard configurations the DCU3 - system can have customized configura-

tions, as required for special applications. The description of such configurations can be
added to this document or can be combined into a project-specific document.

Design, installation, start-up and use of the fermentor system are shown in the extra operating manual
of this unit. More detailed technical information on the hard- and software structure, the system instal­lation, etc., is given in the extra „Technical Manual DCU3 - system“. If the DCU3 - system should be
used together with a host computer the corresponding protocol for communication is described in the
manual „DCU-Host Communication“. Both these manuals are available on request.

The digital control system DCU3 is one example of Sartorius BBI Systems´ product program of sophis­ticated fermentation and peripheral laboratory equipment. For further information about this device and
our complete product program please contact the

 Sartorius BBI Systems GmbH

Schwarzenberger Weg 73-79
D - 34212 Melsungen
Tel.: [phone] - 71 34 00, Fax: [phone] - 71 37 02
e-mail: [e-mail]

WebSite http://www.sartorius-bbi-systems.com
or your local representative of Sartorius BBI Systems GmbH or Sartorius AG.
Printed in Germany

© Sartorius BBI Systems GmbH. This document describes the device at the time of it s publication. Modification s

of the equiment and changes of the related documentation are preserved. No part of the documentation shall be
changed or duplicated or reprocessed for other purposes by third parties without our written permission.

Printed in Germany

Operators Handbook DCU3 – System

Introduction

BAEDCU3 - Rev. 4.6 - 0504

Operators Handbook DCU3 – System

Contents

BAEDCU3 - Rev. 4.6 - 0504

Contents Page

Introduction

1 Design and Function 1 - 1

2 Operating Behaviour

2.1 Switching „off“ and „on“ 2 - 1

2.2 Mains Failure 2 - 1

2.3 Shut Down Function 2 - 2

2.4 Interlocking Functions 2 - 2

3 Function Selection and Inputs

3.1 Operating Terminal 3 - 1

3.2 Inputs 3 - 7

4 Start-Menü „Main“

4.1 General Notes 4 - 1

4.2 Process Information Provided by the „Main“ Menu 4 - 1

5 Main Function „Calibration“

5.1 General Note 5 - 1

5.2 pH - Calibration 5 - 2

5.3 pO2 - Calibration 5 - 4

5.4 Redox - Calibration 5 - 5

5.5 Calibration of Turbidimetry Measurement 5 - 6

5.6 Totalizer for Pumps and Valves 5 - 8

5.7 Calibration of a Balance System 5 - 10

5.8 Flow Calibration 5 - 11

6 Main function „Control Loops“

6.1 Equipment and Functional Principles 6 - 1

6.2 Selection of Controller 6 - 2

6.3 Controller Operation in General 6 - 3

6.4 Parametrization of Controllers, in General 6 - 4

6.5 Temperature Controller 6 - 7

6.6 Stirrer Speed Controller 6 - 9

6.7 Airflow Controller 6 - 10

Operators Handbook DCU3 – System

Contents

BAEDCU3 - Rev. 4.6 - 0504

6.8 pH - Control Function Operating as PID - Controller 6 - 11

6.9 pO2-Control Methods 6 - 12

6.10 pO2 - Cascade Controller with 3 Servo Controllers 6 - 12

6.11 pO2 - Cascade Controller with 4 Servo Controllers 6 - 16

6.12 pO2-Gasmix Controller / O2 – Enrichment 6 - 18

6.13 pO2 - Gasflow Ratio Controller 6 - 19

6.14 Oxygen (O2) – Enrichment Using 2 Massflow Controllers 6 - 22

6.15 Foam Controller 6 - 24

6.16 Dosing Pump Controller 6 - 26

6.17 Level Controller 6 - 27

6.18 Weight Controller 6 - 29

6.19 Pressure Controller 6 - 30

6.20 Gravimetric Dosing Controller 6 - 31

6.21 Setpoint Profiles 6 - 33

6.22 Timers 6 - 35

6.23 Alarm Limits of Process Values 6 - 37

6.24 Alarms of Digital Inputs 6 - 39

7 Main function „Batch Control“

7.1 General 7 - 1

7.2 Sequences 7 - 1

7.3 Process Time 7 - 5

8 Main Function „Recipes“

8.1 Overview 8 - 1

8.2 Recipe Selection 8 - 1

8.3 Controller Parameters in Recipes 8 - 3

8.4 Setpoint Profiles 8 - 4

8.5 Timers in Recipes 8 - 5

8.6 Process Value Alarms in Recipes 8 - 6

8.7 Digital Input Alarms 8 - 7

9 Main function „Maintenance“

9.1 Overview 9 - 1

9.2 Manual Operation in General 9 - 2

9.3 Manual Operation for Digital Inputs 9 - 2

9.4 Manual Operation for Digital Outputs 9 - 4

9.5 Manual Operation of Analog Inputs 9 - 6

Operators Handbook DCU3 – System

Contents

BAEDCU3 - Rev. 4.6 - 0504

9.6 Manual Operation for Analog Outputs 9 - 8

9.7 Settings of Measurement Ranges 9 - 10

9.8 Connection of External Devices 9 - 11

9.9 Host Interface 9 - 12

9.10 Peripheral Interface 9 - 14

9.11 Balance Interface 9 - 15

9.12 System Settings 9 - 16

9.13 Service / Diagnostics 9 - 17

10 Main Function „Documentation“

10.1 Selection Menu 10 - 1

10.2 Report Printer 10 - 1

10.3 Recorder Configuration 10 - 3

11 Main Function „Password“ 11 - 1

12 Main Function „INFO“ 12 - 1

13 Alarms

13.1 Alarm Messages 13 - 1

13.2 Alarm Menu 13 - 2

14 Supplement

14.1 Alarms, Meanings and Remedial Measures (Troubleshooting) 14 - 1

14.2 Trouble Shooting for the DCU-System 14 - 5

14.3 Interlocking Functions 14 - 5

14.4 Abbreviations 14 - 6

14.5 Fermentor - Specific Adjustments of Balance Systems 14 - 8

14.6 Arrangement and Assignment Plans 14 - 9

14.7 Declaration of Conformity with EC-Directives, Standards and

Technical Specifications 14 - 9

Operators Handbook DCU3 – System

Contents

BAEDCU3 - Rev. 4.6 - 0504

Operators Handbook DCU3 – System

1., Design and Function

BAEDCU3 - Rev. 4.6 - 0504 1 - 1

1 DESIGN AND FUNCTION

The Digital Measurement and Control System DCU3 has been especially developed for the automa­tion of fermentor systems. The hardware is based on an industrial 32 bit VME bus micro processor
system. All measurement and control functions are implemented in the software. The software is
stored on a PC-card, which can easily be replaced for extensions of the system by new versions.

For the fermentors of the BIOSTAT

®

series the Sartorius BBI Systems GmbH offers a broad range of
standard configurations of the DCU3 – system, which consider the features of the individual type of
fermentor. However, the extent of functions implemented for a delivered system will always depend on
the specifications of the customer, as agreed prior to ordering of the fermentor system. Therefore even
specific customized configurations are possible.

Standard functions are data acquisition, sensor calibration, alarm monitoring and control of operation
conditions. Additional software modules provide control of process conditions by changing parameters
depending on running time and state of the process. This includes setpoint profiles for controllers,
timer functions for pulsed actuators, dosing counters, etc. Complete sets of process parameters may
be predefined as recipes to allow performing of reproducible process sequences.

The DCU3 can be integrated into hierarchical automation systems via its remote interfaces. A host
computer system can be connected, such as the proven MFCS-Systems, for instance, providing func­tions like graphical visualization of processes, data acquisition and storage, process protocols, etc.

Operators Handbook DCU3 – System

1., Design and Function

BAEDCU3 - Rev. 4.6 - 0504 1 - 2

Operators Handbook DCU3 – System

2., Operating Behaviour

BAEDCU3 - Rev. 4.6 - 0504 2 - 1

2 OPERATING BEHAVIOUR

The DCU3 - system stores all parameters which are adjustable by the operator (setpoint, calibration
parameters, profiles, etc.) in a battery buffered memory. Hence these parameters are still available
when the DCU3 system is switched off and restarted again.

For enabling the outputs of the DCU3 - system and of several system functions, which directly act on
the fermentor system, 4 categories of switching-off or power failure, respectively, are differentiated:

1. Switching „off“ and „on“ using the mains switch at the front panel (see pos. 3 in fig. 1-1).

2. Shut down due to mains failure.

3. Emergency cut-off via the „SHUT-DOWN“-key at the operating terminal or using the mains
switch of the supply unit or cabinet of the fermentor (see BIOSTAT

®

MD, ED or BIOSTAT®

C-DCU3, UD, for instance).

4. Interlocking functions for system outputs.

2.1 Switching „off“ and „on“

The DCU3 - system is switched-on or off, respectively, via the mains switch on the front panel. After
being switched-on (again) the DCU3 will start at (return to) a defined state of operation:

 All controllers are „off“, a ctuators are in rest position
 All timers are „off“ (stopped )
 No recip e loaded, no program (sterilization for example) active

2.2 Mains Failure

In the case of a (mains) power failure, after being restarted, the DCU3 - system continues its activities
as follows:

 Controllers ru n on with the setpoint, which has been adjusted at the time of the power failure
 Timers and setpoint profiles will be continued
 Sequence s, such as sterilization programs, and recipes will be continued

The operator can set a maximum power failure time (FAILTIME) in the „maintenance“ menu. This is a
specific feature of the DCU3 - system. When the power failure lasts longer than the preset FAILTIME,
then the DCU3 - system behaves as if being switched-off with the mains switch, i.e. the system will be
shut down and set to a defined basic state.

After a power failure the system generates the message „Power Failure“, together with the time and
duration of the failure. If the maximum power failure time has expired (see „FAILTIME“), the system
displays the message „Pwf stop ferm“ with time and duration of the failure. See also the description of
the „Alarm messages“ in the supplement.

Operators Handbook DCU3 – System

2., Operating Behaviour

BAEDCU3 - Rev. 4.6 - 0504 2 - 2

2.3 Shut Down Function

The shut down function can be released by :

 Enabling the „SHUT DOWN“ key on the operating terminal and
 Enabling the mains switch of the fermentor (located on the supply unit or cabine t).

In the shut down state all outputs are switched over to their predefined safe state. Other active func­tions of controllers, timers, profiles, recipes and sterilization are not effected.

 During the SHUT DOWN state you can change any of the active functions, as required.
 If the SHUT DOWN state is enabled, the DCU3 - system displays the alarm message „Shut

Down DCU“ or „SHUT DOWN FERMENTOR“

Pressing the „SHUT DOWN“ key again or restarting the fermentor supply unit with the emergency
switch terminates the shut down function. Then all outputs of the DCU are reactivated.

2.4 Interlocking Functions

Interlocking functions trigger the outputs for functions which are important for operational safe ty, i.e.:

 Fixed safety functions which cannot be changed by the user.
 User-definable safety functions.

An interlocking function switches certain outputs of the DCU3 over into their predefined safety state.
However, this will not effect the course of controllers, timers, profiles, recipes and of the sterilization.
For details about specific functions see section „Interlocking functions“ in the supplement.

If the cause for release of an interlocking function is no longer present, the safety state of the corre­sponding output will be cancelled and the output returns into its operating state.

 The safety state of an output is the same as the state during SHUT DOWN.
 The state of the output displayed in the menu „MAINTENANCE, MANUAL OPERATION,

DIGITAL OUTPUTS“ and „ANALOG OUTPUTS“ is „lock“.

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 1

3 FUNCTION SELECTION AND INPUTS

3.1 Operating Terminal

The DCU3 - system has an especially developed touch screen terminal for display of all process pa­rameters and for operation of the entire unit. This „touch terminal“ has integrated „touch keys“ where
the operator can select the menus and the related subfunctions, enter data and select and switch-over
the modes for fermentor operation. In general the terminal is operated simply by pressing the screen
at the position of the displayed keys.

The touch terminal is adjustable to provide an optimum angle of vision:
DCU-Tower :
 BIOSTAT

®

B-DCU

1. Unscrew the locating screw of the support at the rear of the
terminal a little.

2. Push the terminal backward at its upper edge or pull until
the display can be read best. Tighten the screw again.

DCU3-System in table top housing:
 BIOSTAT

®

MD-DCU3, Q-DCU-

3, C/CT-DCU3

1. Push the locking device on right hand of the terminal (see
push button 4 in fig. 1-1)

2. Pull the terminal at its lower edge or push backward, until
you achieve an angle where the display can be read best.

3. Release the locking device to fix the arrangement.

Rack version of DCU3 systems :
 BIOSTAT

®

D-DCU3, customized

pilot- and production fermentors

 The possible way of setting the angle depend s on the

mounting of the terminal in the rack.

3.1.1 Structure of the Touch Screen Display

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 2

Structure of the Touch Screen Display, on the page above shown for the „Main“ menu:
 1. line: Status line:

TAG Used for

hhhh:mm Display and Input of process time
Fermentation (etc.) Display of operating state. Possible displays are:

− Fermentation: System is in „Fermentation“ state

− Sequence: System runs a sequence

− Recipe 1..4: System runs a recipe (1..4)

18.01.00 14:03:11 Display of actual date and time in formate:
dd.mm.yyyy hh:mm:ss

 2. line: Alarm line, display of alarms (showing the latest alarm)
 3. line: name of active function in the workin g area
 Workin g area: display of schematic setup of fermentor system and peripheral equipment;

– MAIN 2 : next „Main“-page
– the items displayed depend on the active function a nd can include symbols for devices,

process values, parameters, modes and settings;

– the displays of the items are designed as touch keys for direct access to submenus for

selecting functions and entering parameters.

 Lowest line: Main function keys (also designed as touch-keys) for selection of submenus

and subfunctions, where parameters should be entered and operating modes should be set.

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 3

3.1.2 Function al Keys of the Working Area

For a selected function the lowest line of the working area can have additional touch keys, which are
especially assigned to this function and allow for direct access to the corresponding submenus.

 Example: Operating display of the pO

2

- controller with touch keys:

 The following touch keys for function selection are available in the working area of the oper-

ating displays:

Selection key Function

Exit Closes the actual display
PARAM Request for display of related parameters
PV - Alarm Request for display of related process value alarms
PROFILE Request for display of related setpoint profiles
CALIB Request for display of related calibration function

Available keys not shown in this example are

CLOOP Selection of the related controller menu
CLOOPx Selection of additional controller displays
MAINx Request for display of related process overviews
TIMER Request for display of related timer functions
DI ALARM Request for display of related digital input alarms

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 4

3.1.3 Selection of Menus and Entering of Parameters

The operation of the DCU3 - system is organized systematically. Related tasks of fermentor operation
are combined in functional groups - the „main functions“ listed below. A main function can be directly
activated at any time during the running process from any submenu by pressing the corresponding
main function touch key at the screen.

Main function Display, use

Main Graphic overview of the entire fermentor system showing the most important

process parameters and allowing for direct access to the related functions.
Calibration Calibration of sensors and pumps, taring of balance systems
Control Loops Operation of the controllers and related setpoint profiles and timers
Batch Control Operation of serial steps, batch processes, etc., such as sterilization runs
Recipes Operation of 4 recipes with preset controller parameters, setpoint profiles, tim-

ers and alarm parameters
Maintenance Manual access to inputs and outputs, measurement ranges of process values,

parameters of remote systems (such as host computers, balance systems) and

to the maintenance (service) functions
Documentation Operation of recorders and printers for documentation of the process
Info Information about the installed software / general notes

There are two possible methods to select a menu, step forward to a subfunction and enter parame­ters. As an example here are the possible methods for setpoint adjustment of the stirring speed:

 Stepping through the menu tree as known from the former DCU1- and DCU2- systems:

1. Select the main function „Control Loops“ by pressing the touch key

2. Select the „Stirrer“ controller from the overview of controllers

3. Adjust the setpoint

 Enabling the data entry function directly from the main menu. This is accomblished by object

(based) linking of the actual stirrer speed display in the main menu to the related controller
functions, i.e. „stirrer controller, setpoint profile and alarm limits“:

4. Press the „Stirrer“ - touch key in the working area of the main menu. The display directly
switches over to the menu of the stirrer controller.

5. Adjust the setpoint.

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 5

3.1.4 „Tou ch keys“ in the Menu „Main“

After switching on of the system the graphical overview in the menu „Main“ provides a schematic dis­play of the main functional elements of the individual fermentor system, together with the most import
process parameters and the „touch keys“ for selection of the related functions:

 Only for the single unit at fermentor systems with one culture vessel
 As an overview of all subunits at fermentor systems with 2…4 culture vessels

At multible vessel fermentor systems the main menus of the subunits can be accessed as follows:

 Via the touch key integrate d in the overview display showing the vessel no. of the subunit

(only for DCU3 systems available from about April 2002 on and as far as implemented).

 Via the direct function key CHANGE UNIT

Menu „Main“: Direct access to the main menus of subunits at fermentors with 2..4 culture vessels:
Example: BIOSTAT

®

B-DCU twin Example: BIOSTAT® B-DCU quattro

 The touch key „All vessel“ can be used to return to the overview display of all units.

The direct function key CHANGE UNIT cyclically switches over the displays of the main menus of all
units and the individual subunits:

 All vessels  v essel 1  vessel 2  (vessel 3, 4, if available)  all vess els

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3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 6

Switching over the main menu dis­plays for 2…4 culture vessels via
direct function key CHANGE UNIT:



CHANGE UNIT





CHANGE UNIT



.....

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 7

3.1.5 Direct Function Keys

The direct function keys on right hand of the „Touch Terminal“ allow for direct access to the system:

SHUT DOWN : Pressingthis key sets all analog and digital outputs into a safe state. An active

SHUT DOWN state is indicated by lighting LED in the key. Repeatedly pressing the key
cancels (releases) the SHUT DOWN state and the system returns to its previous state.

ACK : If an alarm message occurs, a red LED in the ACK - key lights. Pressing the ACK - key then

enables the alarm menu on the display.

REM : Pressing the REMote control key allows for the transmission of data from the host to the

DCU system. Effective only if a host computer is connected to the DCU-system.

CHANGE UNIT : Switching-over of the operating terminal. Applicable for DCU3-system which are

prepared for controlling several fermentors/culture vessels.

3.2 Inputs

3.2.1 Numerical and Non-numerical Inputs

 Example for entering numerical inputs, shown here for the temperature setpoint:

1. Press either the touch-key „Temp“ in the work­ing area of the „main“ menu or the key “SETP”
in the menu TEMP Control Loop
A touch key pad fades in for data input.

2. Enter the new setpoint. For this consider the
permissible setpoint range, as indicated.

3. At erroneous inputs delete the entry with CAN­CEL and enter the correct numbers.

4. Confirm the input with the „Ok“-key.

5. The system closes automatically the touch key
pad. The new setpoint is displayed.

 Input of operating mode, i.e. controller modes:

1. Press the touch key „MODE“;
a window with the selectable modes fades in.

2. Press the touch key of the intended mode, i.e.
„off“.

3. At selection of a wrong mode, delete with CAN­CEL and select again the correct mode

4. The selection window closes and the display
shows the new mode.

Operators Handbook DCU3 – System

3., Function Selection and Inputs

BAEDCU3 - Rev. 4.6 - 0504 3 - 8

 Input of text:

1. Enter the text with a max. number of letters
(Range).

2. At wrong inputs delete the entry using the „<-“
key or CANCEL.

3. Confirm the Entry with „Ok“. The system closes
the keypad and displays the text.

 Selection boxes (slide r): The slider can be moved as follows:

1. Pressing the arrow key

2. Moving the white zone within the slider

3. Pressing the shaded zone at the relative posi­tion of the table, which should be accessed

Special Notes

 What do touch keys indicate, whose label appears in black & white dithered („light“) letters?
 If a controller´s mode is set to „auto“, for instance, the data entry for the controller output is

locked. This locking of an entry against inputs is indicated on the „OUT“ key. The letters
then are displayed in black & white dithering („light“).

3.2.2 Password - System

System settings and functions, that are restricted for use by authorized personnel only, are protected
by a password. Among others these are, for instance, the setting of controller parameters (such as
PID), the setting of interface parameters and the manual operating mode.

 For more detailed information refer to section “Main function “Password””.

Operators Handbook DCU3 – System

4., Start-Menü „Main“

BAEDCU3 - Rev. 4.6 - 0504 4 - 1

4 START-MENÜ „MAIN“

4.1 General Notes

The „Main“ menu is displayed after switching on the DCU3 - system. With the new „object-based“ dis­play of entries and the direct selection of submenus and functions for data input and mode selection,
the main menu is the control center for operation during a fermentation run.

The schematic display of the culture vessel together with the connected peripheral assemblies, the
symbols for stirrers, pumps, totalizers, balance system and the location of the electrodes facilitates the
overview over the state of the process parameters. Above this it is the starting point for easy access to
the submenus and subfunctions for inputs and selections.

4.2 Process Information Provided by the „Main“ Menu

The main menu displays the process values together with schematics of the related component parts
of the fermentor system:

 Measured values for pH, pO

2

, foam, etc.;

 Inputs of external actuators, such a s motor control, massflow controller;
 Processed values, such as dosing volumes of pumps, totalizers, calculated values of arith-

metic functions, etc.;

 Signals of external device s connected to the DCU3 - system, such as a balance system;

The extent of displayed entries, process values and parameters depends on the configuration of the
DCU3 - system for the related fermentor system. The table on next page gives an overview on com­mononly applied tags and entries.

Operators Handbook DCU3 – System

4., Start-Menü „Main“

BAEDCU3 - Rev. 4.6 - 0504 4 - 2

4.2.1 Alarms

 If a process value exceeds its alarm limit or if a device is switched over to an alarm state the

backround color of the corresponding symbol changes to red (in this „laser-printed“ manual
shown light-grey, see example for the entry of foam measurement).

4.2.2 Invalid Process Values

 If a process value is „invalid“ the display changes to „---„, see example „flow“:

4.2.3 Direct Function Keys and Headline Text at the Touch Display

 Direct Fun ction keys on the touch display have the background colour grey/white.
 Headline texts (background colour white) label indicate a correlation of the functions of the

subsequent keys

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 1

5 MAIN FUNCTION „CALIBRATION“

5.1 General Note

All calibration functions required for routine operation of the fermentor can be executed using the main
function „calibration“. You can select the following functions via the corresponding selection menu:

 Selection menu „Calibration“:

 The entries refer to the following functions:

– „Sensors“ : calibration of the electrodes using calibration buffers and standard conditions
– „Totalizer“ : calculation of the delivery of the addition agent pumps for dosing counters
– „Balance“ : the functions required for (pre)setting of balan ce systems, such as zero taring

and tare correction

 You will enter all inputs at the touch terminal. Context based information displayed on the

terminal will guide you through the individual menus, telling you which inputs and selections
are required. The DCU3 - system automatically adapts the related (measured or calculated)
process values to the settings resulting from the calibration.

 The calibration parameters will be stored when the DCU3 - system is switched off. Hence

the DCU3 - system will use these settings again for the calculation of parameters, when it is
restarted for continueing a process or for a new process, until the calibration is done again.

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 2

5.2 pH - Calibration

The pH electrode is calibrated by a two-point calibration using liquid buffers. The calibration is done
before the electrode is installed in the culture vessel. For details about preparing of the pH-electrode
and handling during calibration see the operating information delivered by the manufacturer. For de­tails about mounting the electrode into the culture vessel, see the fermentor´s operating manual.

The calibration determines the „zero drift“ and „slope“ of the electrode. The measured pH-value is cal­culated from the electrode voltage using the Nernst equation, considering the „zero drift“, „slope“ and
„temperature“. During calibration the temperature is entered manually. For pH-measurement during
the process temperature effects are compensated via the measured temperature in the fermentor.

The impact of heat during the sterilization can cause a zero drift of the electrode. To compensate for
such effects the DCU3 - system allows to recalibrate the pH-electrode during the process. You can
measure the pH-value in a sample taken from the fermentor and enter this value into a corresponding
menu. The software recalculates the zero drift and displays the corrected „in-situ“ pH-value afterwards.

The operating display for the pH - electrode shows the pH value, the electrode voltage and the elec­trode parameters „zero drift“ and „slope“. Thus the functioning of the electrode can be easily checked.

5.2.1 Operating Display

Tag Entry Displayed value or function, required input

pH pH Display of measured pH value,

input of pH-value measured in sample for recalibration
ELEC mV Display of measured electrode voltage (raw signal)
TCOMP Display “temperature compensation”
TEMP Display of temperature for temperature compensation
ZERO mV Display of zero drift
SLOPE mV/pH Display of slope
Start Calibration Enabling the calibration function
Start Recalibration Enabling the recalibration function (during the process)

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 3

 Additional touch keys, tags and entries displayed depending on the selected function:

Tag Entry Displayed value or function, required input

TMPCO degC Input of temperature for manual temperature compensation
BUFFZ pH Input of pH-value of zero buffer

− note pH-value on the buffer bottle for the actual temperature

BUFFS pH Input of pH-value of slope buffer

− note pH-value on the buffer bottle for the actual temperature

5.2.2 Calibration

The pH - electrode is calibrated before installation into the culture vessel, e.g. prior to the sterilization.

Tip: Since the heat impact during the sterilization and chemical compounds of the culture me-

dium may effect the measurement characteristics of the electrode, it must be calibrated and
checked for proper function regularly (i.e. prior to any new fermentation run).

1. Start the calibration routine by pressing the „Start Calibration“ touch key.

2. Follow the instructions given in the related submenus.

5.2.3 Recalibration

 Via these steps you can adapt the pH-measurement function to changing measuring char-

acteristics of the electrode, as it may be caused by heat impact during the sterilization or by
chemical reactions of the electrolyte with the culture medium, for instance:

1. Measure the actual pH-value in a sample taken from the running fermentation, using con­ventional pH-measuring techniques.

2. Start the calibration by pressing the „Start Recalibration“ touch key.

3. Follow the instructions given in the related submenus.

 The DCU-system automatically recalculates the zero drift caused by the sterilization and

displays the corrected pH-value.

5.2.4 Special Notes

 If necessary the values for „zero drift“ and „slope“ can also be entered directly in the corre-

sponding sections of the display.

 The electrode has a restricted maximum lifetime which depends on the operating conditions

and the application. The electrode should be serviced or replaced, whenever the functional
check and the calibration indicate a malfunctioning.

 The pH - electrode must be serviced or replaced if :

– the zero drift is beyond the range of -30 ...+30 mV
– the slope is beyond the range of 56...59 mV/pH

 You'll find specific information about recommended service periods and estimated lifetime of

the electrode in the manufacturer´s documentation included in the delivery of the electrode.

 Depending on the type of fermentor and the delivered pH-electrode, the operation and main-

tenance measures required for the electrode may differ from the information herein. You'll
find more detailed information about proper handling of the electrode during calibration and
installation into the culture vessel in the Operating Manual of the fermentor.

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 4

5.3 pO2 - Calibration

The pO2 - electrode is calibrated in terms of percentage oxygen saturation, „% pO2“. The calibration is
a two-position calibration. In a fermentor the oxygen-free culture medium is the zero reference and the
medium saturated with oxygen is the „100 % pO

2

“ - reference. The pO2-electrode is calibrated while it
is installed in the culture vessel and after the sterilization. Therefore the calibration considers possible
interferences resulting from heat impact or chemical effects during sterilization.

 In in-situ sterilized culture vessels you can enter the current of the electrode measured at

the end of the sterilization cycle as zero reference of the electrode.

 If it is impossible to measure the zero current before air is introduced, you can connect a ni-

trogen source to the air input and gas the vessel with oxygen-free nitrogen to replace the
oxygen dissolved in the medium.

 The slope can be measured after gassing the medium with air (or gas mixtures containing

oxygen) at the operating conditions intended for the process. During the process the DCU ­system calculates the actual pO

2

considering the zero reference, slope and temperature.

The structure of the operating display for calibration of the pO

2

-electrode is nearly the same as for the
pH-calibration. See the display on your DCU - system for details or refer to the pH - calibration display.
The display shows the „pO

2

-saturation“ (% pO2), the actually measured electrode current, the actual
temperature and the zero and slope current together with the calibration conditions. This, in addition,
allows a simple function control of the pO

2

-electrode.

5.3.1 Calibration

5.3.1.1 Zero Calibration

1. Before starting the zero calibration: sterilize the vessel (i.e. run the sterilization cycle at in­situ sterilizable fermentors) or
– connect a supply of oxygen-free nitrogen and ga s the medium until any dissolved oxygen

is exhausted.

2. Inititate the calibration of the electrode´s zero via „Start ZERO Calibration“. Follow the in­structions given in the calibration menu.

 If the displayed zero current (ZERO: ....) is not in the range of 0 ... +10 nA, the pO

2

-

electrode must be checked and serviced.

5.3.1.2 Calibration of Slope

1. Gas the medium with air (or the intended gas mixture containing oxygen) at the conditions
(flow rate, pressure, temperature) intended for optimum oxygen supply. A constant elec­trode current will indicate that the medium is saturated with oxygen.

2. Inititate the slope calibration via „Start SLOPE Calibration“ and follow the instructions given
in the calibration menu.

 If the measured current re mains below 30 nA, the electrode must be checked and serviced.

5.3.2 Special Notes

 At a first use or at any time the pO

2

-electrode has been disconnected from the amplifier for
more than 5 ... 10 min. it must be polarized. This polarization takes at least 6 h (the time will
be shorter, if the electrode is disconnected for only a few minutes). See information in the
Operating Manual of the fermentor or in the documentation delivered with the electrode.

 If necessary the „Ze ro“ and „Slope“ can be entered manually into the corresponding fields.

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 5

5.4 Redox - Calibration

The Redox calibration is in fact a functional check. You will measure a calibration buffer and compare
the measured value with the reference indicated on the buffer bottle. If these values are different, the
Redox can be entered manually. The DCU - system then calculates a corresponding correction factor.

5.4.1 Operating Display

Tag Entry Displayed value or function, required input

REDOX mV Display of combined electrode voltage
CHECK mV Display of combined electrode voltage of last calibration
Start Check Electrode Enabling calibration of the Redox electrode

 Additional touch keys, values and functions available in this display:

REFBU mV Enter reference voltage of redox buffer

5.4.2 Functional Check

The electrode function is checked before it is mounted into the culture vessel and therefore prior to the
sterilization. Since the heat impact of sterilization or chemical reactions with compounds of the culture
medium may effect the measuring characteristics of the electrode its function should be checked regu­larly, i.e. prior to any next use and, if wrong operation is suspected, after a fermentation run.

1. Place Redox electrode in a beaker filled with the reference buffer

2. Enable functional check via „Start check electrode“. Follow the instructions of the menu.

5.4.3 Special Notes

 If the measured buffer Redox and the value on the buffer bottle deviate by more than 6 mV

(about 3%) the electrode must be serviced. See documentation delivered with the electrode.

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 6

5.5 Calibration of Turbidimetry Measurement

Calibration of the turbimetry measurement probe is a „single-step“ procedure evalulating the „zero de­viation“ of the sensor is. For this the sensor is placed into particle- and bubble-free deinonized water.

The system calculates the turbidimetry as the arithmetical mean of the value measured during a de­fined measuring time in terms of „absorption units, AU“. For calculation the system considers the zero
deviation and a selectable damping factor „DAMP”. To obtain stable turbidimetry measurements, the
damping factor „DAMP“ can be selected in 4 stages.

The operating display of the turbidimetry sensor includes the data field for absorption units (AU), the
percentage sensor raw signal [%] and the zero deviation against „0 AU“. This allows for an easy func­tional check of the sensor. The lamp contained in the turbidimetry sensor can be switched on and off
via the „Sensor Calibration“ - menu, see LAMP-entry

1)

.

5.5.1 Operating Display

Tag Entry Displayed value or function, required input

TURB AU Display of process value in 0...6 AU (Absorbing Units)
ELEC % Display of percentage raw signal of the sensor
ZERO % Display of zero deviation after calibration
LAMP

1)

On/off Display and selection of switching state of lamp in the sensor

DAMP 1 ... 4 Display and input of signal damping. The input signal is proc-

essed as the mean value of a floating reference window.
Damping factors base upon 4 selectable reference windows:

- step 1 = 6 s; step 2 = 12 s; step 3 = 30 s; step 4 = 60 s

Start Calibration Enabling the calibration routine

 Additional touch keys, values and functions available in this display:

BUFFZ AU Display of zero solution

1)

Only Fundalux I – system, not applied with Fundalux II (available as option from 2004 on)

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 7

5.5.2 Calibration

For calibration of the turbidimetry sensor proceed as follows.

1. Start the calibration via „Start Calibration“

2. Follow the instructions of the calibration menu.

5.5.3 Special Notes

1. If the lamp

1)

is switched on, it will be kept in „on“-state when the DCU3 - system is switched

off and on again.

2. If required, the percentage zero deviation can directly be entered in the ZERO-entry.

Operators Handbook DCU3 – System

5., Main Function „Calibration“

BAEDCU3 - Rev. 4.6 - 0504 5 - 8

5.6 Totalizer for Pumps and Valves

For monitoring of the corrective agent consumption the dosing times of the pumps or of the dosing
valves are totalized and used as process values. The DCU3 - system converts the dosing times into
delivered volumes considering the specific flowrates of the pumps or of the dosing valves.

The dosing counters can be zeroed at any time via the operating display. If the specific flowrates are
known, you can enter them directly via the touch display. If the flowrates must be evaluated you can
use the „Calibration Totalizer“ function. Furthermore the flowrates can be calculated automatically dur­ing the calibration process from the measured running time and the entered delivery volume.

The standard configurations of the DCU-system include calibration routines and dosing counters for
acid, base, antifoam, feed, harvest and substrate. Since the calibration and dosing counter functions
are the same for all pumps and dosing valves, only those for the acid pumps will be described herein.

5.6.1 Operating Display

Tag Entry Displayed value or function, required input

ACID ml Display of delivered volume of liquid
FLOW ml/min Display of calculated delivery or input of either specific

pump delivery or valve flow, as far as known
Start Calibration Enabling the calibration
Reset Totalizer Resetting the dosing counter to zero
PV ALARM Enabling the alarm display
CLOOP Selection of the controller menu

 Additional touch keys, values and functions available in this display::

VOLUME ml Input of volume delivered during calibration