Metrohm 877 User Manual

877 Titrino plus
Manual
8.877.8003EN
Metrohm AG CH-9100 Herisau Switzerland Phone +41 71 353 85 85 Fax +41 71 353 89 01 info@metrohm.com www.metrohm.com
877 Titrino plus
8.877.8003EN
Manual
04.2013 jb/ebe
Teachware Metrohm AG CH-9100 Herisau teachware@metrohm.com
This documentation is protected by copyright. All rights reserved.
Although all the information given in this documentation has been checked with great care, errors cannot be entirely excluded. Should you notice any mistakes please send us your comments using the address given above.
Documentation in additional languages can be found on
http://documents.metrohm.com.
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Table of contents

1 Introduction 1
1.1 Instrument description ......................................................... 1
1.1.1 Titration and measuring modes ................................................ 1
1.1.2 Connectors .............................................................................. 2
1.1.3 Intended use ........................................................................... 2
1.2 About the documentation ................................................... 2
1.2.1 Symbols and conventions ........................................................ 2
1.3 Safety instructions ................................................................ 3
1.3.1 General notes on safety ........................................................... 3
1.3.2 Electrical safety ........................................................................ 4
1.3.3 Tubing and capillary connections ............................................. 5
1.3.4 Flammable solvents and chemicals ........................................... 5
1.3.5 Recycling and disposal ............................................................. 5
2 Overview of the instrument 6
Table of contents
3 Installation 8
3.1 Setting up the instrument .................................................... 8
3.1.1 Packaging ................................................................................ 8
3.1.2 Checks .................................................................................... 8
3.1.3 Location .................................................................................. 8
3.2 Connecting a sensor ............................................................. 8
3.3 Connecting a stirrer ............................................................ 10
3.4 Connecting a balance ......................................................... 11
3.5 Connecting a keyboard, printer and other USB devi-
ces ........................................................................................ 11
3.6 Connecting instruments to the remote connector .......... 14
3.7 Attaching the exchange unit ............................................. 15
4 Titrations 16
4.1 Monotonic equivalence point titration (MET) .................. 16
4.2 Endpoint titration (SET) ..................................................... 16
5 Operation 18
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5.1 Switching the instrument on and off ............................... 18
5.2 Fundamentals of operation ............................................... 19
5.2.1 The keypad ............................................................................ 19
5.2.2 Structure of the dialog windows ............................................ 20
5.2.3 Navigating in the dialog ......................................................... 20
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Table of contents
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5.2.4 Entering text and numbers ..................................................... 21
5.2.5 Selecting from a selection list ................................................. 22
5.3 Formula editor .................................................................... 22
5.4 Methods .............................................................................. 24
5.4.1 Creating a new method ......................................................... 24
5.4.2 Saving a method ................................................................... 25
5.4.3 Loading a method ................................................................. 26
5.4.4 Exporting a method ............................................................... 27
5.5 Control ................................................................................. 28
5.6 Sample data ........................................................................ 29
5.6.1 Entering sample data in the main dialog ................................ 29
5.6.2 Requesting sample data at the start of the determination ...... 30
5.7 Sample table ....................................................................... 31
5.7.1 General ................................................................................. 31
5.7.2 Editing the sample data ......................................................... 32
5.7.3 Sending the sample size from a balance ................................. 34
5.8 Carrying out a determination ............................................ 34
5.9 Live modifications .............................................................. 36
5.9.1 Editing the sample data of the running determination ............ 36
5.9.2 Editing the sample table while a determination is running ...... 37
5.9.3 Editing the live parameters ..................................................... 38
5.10 Results ................................................................................. 39
5.11 Statistics .............................................................................. 40
5.12 Printing a report manually ................................................. 42
5.13 Manual Control ................................................................... 43
5.13.1 Dosing ................................................................................... 44
5.13.2 Measuring ............................................................................. 48
5.13.3 Stirring .................................................................................. 49
6 System settings 51
6.1 Basic settings ...................................................................... 51
6.2 Managing sensors .............................................................. 55
6.2.1 General ................................................................................. 55
6.2.2 Editing the sensor data .......................................................... 55
6.3 Managing solutions ............................................................ 57
6.3.1 General ................................................................................. 57
6.3.2 Editing the solution data ........................................................ 57
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IV
6.4 Managing common variables ............................................ 59
6.4.1 General ................................................................................. 59
6.4.2 Editing common variables ...................................................... 60
6.5 File management ................................................................ 61
6.6 Configuring external devices ............................................. 62
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7 Parameters 67
Table of contents
6.7 Instrument diagnosis .......................................................... 65
6.7.1 Loading program versions and language files ......................... 65
6.7.2 Diagnosis functions ............................................................... 66
7.1 Monotonic equivalence point titrations (MET) ................ 67
7.1.1 Start conditions ..................................................................... 67
7.1.2 Titration parameters .............................................................. 68
7.1.3 Stop conditions ..................................................................... 73
7.1.4 Evaluation ............................................................................. 74
7.1.5 Calculation ............................................................................ 77
7.1.6 Statistics ................................................................................ 79
7.1.7 Reports .................................................................................. 79
7.2 Endpoint titrations (SET) .................................................... 81
7.2.1 Conditioning ......................................................................... 81
7.2.2 Start conditions ..................................................................... 82
7.2.3 Titration parameters .............................................................. 84
7.2.4 Control parameters EP1 ......................................................... 86
7.2.5 Control parameters EP2 ......................................................... 89
7.2.6 Stop conditions ..................................................................... 89
7.2.7 Calculation ............................................................................ 90
7.2.8 Statistics ................................................................................ 92
7.2.9 Reports .................................................................................. 92
7.3 pH calibration (CAL) ........................................................... 94
7.3.1 Calibration parameters .......................................................... 94
7.3.2 Buffers ................................................................................... 96
7.3.3 Reports .................................................................................. 97
8 Operation and maintenance 98
8.1 Quality Management and qualification with Metrohm .. 98
9 Troubleshooting 99
9.1 SET titration ........................................................................ 99
9.2 Miscellaneous ................................................................... 100
10 Appendix 101
10.1 Exchange unit ................................................................... 101
10.1.1 Maximum dosing and filling rate .......................................... 101
10.1.2 Parameters for the preparing (PREP) ..................................... 101
10.2 Stirring rate ....................................................................... 102
10.3 Balance .............................................................................. 102
10.4 USB devices ....................................................................... 103
10.4.1 6.2147.000 numerical USB keypad ...................................... 103
10.4.2 Key assignment of a USB keyboard ...................................... 104
10.4.3 PC mouse ............................................................................ 104
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Table of contents
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10.4.4 Printer ................................................................................. 105
10.5 System initialization ......................................................... 105
10.6 Remote interface .............................................................. 106
10.6.1 Pin assignment of the remote interface ................................ 106
10.6.2 Status diagram of the remote interface ................................ 108
10.7 Remote control via an RS-232 connection ..................... 109
10.7.1 Commands and variables ..................................................... 110
10.8 Arithmetic algorithms in the 877 Titrino plus ............... 111
11 Technical specifications 114
11.1 Measuring inputs .............................................................. 114
11.1.1 Potentiometry ...................................................................... 114
11.1.2 Polarizer .............................................................................. 114
11.1.3 Temperature ........................................................................ 115
11.2 Dosing drive ...................................................................... 116
11.3 Interfaces .......................................................................... 116
11.4 Mains connection ............................................................. 116
11.5 Safety specifications ........................................................ 116
11.6 Electromagnetic compatibility (EMC) ............................. 117
11.7 Ambient temperature ...................................................... 117
11.8 Reference conditions ........................................................ 118
11.9 Dimensions ........................................................................ 118
12 Warranty (guarantee) 119
13 Accessories 121
13.1 Scope of delivery .............................................................. 121
13.2 Optional accessories ........................................................ 122
Index 128
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Table of figures

Figure 1 Front 877 Titrino plus ........................................................................ 6
Figure 2 Rear 877 Titrino plus ......................................................................... 7
Figure 3 Connecting pH or redox electrodes ................................................... 8
Figure 4 Connecting a reference electrode ...................................................... 9
Figure 5 Connecting a temperature sensor ...................................................... 9
Figure 6 Connecting a polarizable electrode .................................................. 10
Figure 7 Connecting a stirrer ......................................................................... 10
Figure 8 Connecting a balance ...................................................................... 11
Figure 9 Connecting USB devices .................................................................. 12
Figure 10 Connecting the USB stick ................................................................ 13
Figure 11 Connecting the 6.2147.000 USB keyboard with USB stick and
printer ............................................................................................. 13
Figure 12 Connecting the USB hub with USB stick, printer and the 6.2148.030
RS-232/USB Box (for connecting balances). ...................................... 14
Figure 13 Connecting a remote cable ............................................................. 14
Figure 14 Attaching the exchange unit ........................................................... 15
Figure 15 Reagent dosing for MET .................................................................. 16
Figure 16 Reagent dosing for SET ................................................................... 17
Figure 17 Keypad 877 Titrino plus ................................................................... 19
Figure 18 Directory structure on the USB flash drive ........................................ 61
Figure 19 Rotational speed depending on stirring rate .................................. 102
Figure 20 Pin assignment of remote socket and remote plug ........................ 106
Figure 21 Remote status diagram MET .......................................................... 108
Figure 22 Remote status diagram SET ........................................................... 108
Figure 23 Remote status diagram CAL .......................................................... 109
Figure 24 Connecting the RS-232/USB Box to the PC .................................... 109
Table of figures
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VII
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1 Introduction

1.1 Instrument description

The 877 Titrino plus is a titrator for volumetric titrations for universal appli­cations. Methods can be created and stored under a new name. The methods can be exported to a connected USB flash drive. This function makes it possible for you to copy methods quickly and easily from one instrument to another. The remote connector enables the integration of the instrument in a Metrohm automation system.

1.1.1 Titration and measuring modes

The following titration and measuring modes are supported:
MET
Monotonic equivalence point titration. The reagent is added in con-
stant volume steps.
Measuring modes:
pH (pH measurement) – U (potentiometric voltage measurement) – Ipol (voltametric measurement with selectable polarization cur-
rent)
Upol (amperometric measurement with selectable polarization
voltage)
SET
Endpoint titration at one or two specified endpoints.
Measuring modes:
pH (pH measurement) – U (potentiometric voltage measurement) – Ipol (voltametric measurement with selectable polarization cur-
rent)
Upol (amperometric measurement with selectable polarization
voltage)
CAL
Electrode calibration.
Measuring mode:
pH (calibration of pH electrodes)

1 Introduction

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1.2 About the documentation

1.1.2 Connectors

The instrument is equipped with the following connectors:
MSB connector (Metrohm Serial Bus)
USB (OTG) connector
Sensor connectors
Remote connector

1.1.3 Intended use

The 877 Titrino plus is designed for usage as a titrator in analytical labora­tories. Its main application field is volumetric titration.
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For connecting a stirrer.
The 6.2151.100 adapter can be used to connect, for example, a printer, a USB flash drive or a USB keyboard.
Four connectors for the following sensor types:
– pH or redox electrodes – reference electrodes – polarizable electrodes – temperature sensors (Pt1000 or NTC)
For connecting a Dosimat or sample changer. The Dosimat enables automatic addition of an auxiliary solution.
This instrument is suitable for processing chemicals and flammable sam­ples. The usage of the 877 Titrino plus therefore requires that the user have basic knowledge and experience in the handling of toxic and caustic substances. Knowledge with respect to the application of the fire preven­tion measures prescribed for laboratories is also mandatory.
1.2 About the documentation
CAUTION
Please read through this documentation carefully before putting the instrument into operation. The documentation contains information and warnings which the user must follow in order to ensure safe opera­tion of the instrument.

1.2.1 Symbols and conventions

The following symbols and formatting may appear in this documentation:
Cross-reference to figure legend
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The first number refers to the figure number, the sec­ond to the instrument part in the figure.
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1 Introduction
Instruction step
Carry out these steps in the sequence shown.
Method Dialog text, parameter in the software
File New Menu or menu item
[Next] Button or key
WARNING
This symbol draws attention to a possible life-threat­ening hazard or risk of injury.
WARNING
This symbol draws attention to a possible hazard due to electrical current.
WARNING
This symbol draws attention to a possible hazard due to heat or hot instrument parts.

1.3 Safety instructions

1.3.1 General notes on safety

WARNING
This instrument may only be operated in accordance with the specifica­tions in this documentation.
WARNING
This symbol draws attention to a possible biological hazard.
CAUTION
This symbol draws attention to possible damage to instruments or instrument parts.
NOTE
This symbol highlights additional information and tips.
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This instrument has left the factory in a flawless state in terms of technical safety. To maintain this state and ensure non-hazardous operation of the instrument, the following instructions must be observed carefully.
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1.3 Safety instructions

1.3.2 Electrical safety

The electrical safety when working with the instrument is ensured as part of the international standard IEC 61010.
Only personnel qualified by Metrohm are authorized to carry out service work on electronic components.
Never open the housing of the instrument. The instrument could be damaged by this. There is also a risk of serious injury if live components are touched.
There are no parts inside the housing which can be serviced or replaced by the user.
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WARNING
WARNING
Mains voltage
WARNING
An incorrect mains voltage can damage the instrument.
Only operate this instrument with a mains voltage specified for it (see rear panel of the instrument).
Protection against electrostatic charges
WARNING
Electronic components are sensitive to electrostatic charges and can be destroyed by discharges.
Do not fail to pull the mains cable out of the mains connection socket before you set up or disconnect electrical plug connections at the rear of the instrument.
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1.3.3 Tubing and capillary connections

CAUTION
Leaks in tubing and capillary connections are a safety risk. Tighten all connections well by hand. Avoid applying excessive force to tubing connections. Damaged tubing ends lead to leakage. Appropriate tools can be used to loosen connections.
Check the connections regularly for leakage. If the instrument is used mainly in unattended operation, then weekly inspections are manda­tory.

1.3.4 Flammable solvents and chemicals

WARNING
1 Introduction
All relevant safety measures are to be observed when working with flammable solvents and chemicals.
Set up the instrument in a well-ventilated location (e.g. fume cup-
board).
Keep all sources of flame far from the workplace. Clean up spilled liquids and solids immediately. Follow the safety instructions of the chemical manufacturer.

1.3.5 Recycling and disposal

This product is covered by European Directive 2002/96/EC, WEEE – Waste from Electrical and Electronic Equipment.
The correct disposal of your old equipment will help to prevent negative effects on the environment and public health.
More details about the disposal of your old equipment can be obtained from your local authorities, from waste disposal companies or from your local dealer.
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2 Overview of the instrument

2
5
4
3
1
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Figure 1 Front 877 Titrino plus
Piston rod
1
Of the dosing drive.
Coupling
3
For switching the flat stopcock.
Keypad
5
Contact pins
2
For the data chip.
Display
4
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2
4
8
6
5
9
1
3
7
2 Overview of the instrument
Figure 2 Rear 877 Titrino plus
Electrode connector (Ind.)
1
For connecting pH or redox electrodes with integrated or separate reference electrode. Socket F.
Electrode connector (Ref.)
3
For connecting reference electrodes. Socket B, 4 mm.
USB (OTG) connector
5
For connecting printers, USB sticks, USB hubs, etc.
Temperature sensor connector (Temp.)
7
For connecting temperature sensors of the Pt1000 or NTC types. Two B sockets, 2 mm.
Electrode connector (Pol.)
9
For connecting polarizable electrodes, e.g. double Pt electrodes. Socket F.
Type plate
2
Contains specifications concerning mains voltage and serial number.
Mains connection socket
4
MSB connector
6
Metrohm Serial Bus.
For connecting a stirrer. Mini DIN, 9-pin.
Remote connector
8
For connecting instruments with a remote interface. D-Sub, 9-pin.
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3.1 Setting up the instrument

3 Installation

3.1 Setting up the instrument

3.1.1 Packaging

The instrument is supplied in highly protective special packaging together with the separately packed accessories. Keep this packaging, as only this ensures safe transportation of the instrument.

3.1.2 Checks

Immediately after receipt, check whether the shipment has arrived com­plete and without damage by comparing it with the delivery note.

3.1.3 Location

The instrument has been developed for operation indoors and may not be used in explosive environments.
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Place the instrument in a location of the laboratory which is suitable for operation, free of vibrations, protected from corrosive atmosphere, and contamination by chemicals.
The instrument should be protected against excessive temperature fluctu­ations and direct sunlight.

3.2 Connecting a sensor

Connecting pH or redox electrodes
Figure 3
Connecting pH or redox electrodes
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3 Installation
NOTE
The electrode cable is protected against accidental disconnection of the cable by means of a pull-out protection feature. If you wish to remove the plug, then you must first retract the outer plug sleeve.
Connecting a reference electrode
Figure 4 Connecting a reference electrode
Connecting a temperature sensor or an electrode with inte­grated temperature sensor
Temperature sensors of the Pt1000 or NTC type can be connected to the Temp. connector.
Figure 5
Connecting a temperature sensor
NOTE
The red plug must always be plugged into the red socket at the temper­ature sensor for the purpose of shielding against disruptions.
If you use an electrode with an integrated NTC probe, then you must plug the red plug into the red socket.
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3.3 Connecting a stirrer

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Connecting a polarizable electrode
Figure 6 Connecting a polarizable electrode
NOTE
The electrode cable is protected against accidental disconnection of the cable by means of a pull-out protection feature. If you wish to remove the plug, then you must first retract the outer plug sleeve.
3.3 Connecting a stirrer
You can connect the following stirrers:
801 Stirrer 803 Ti Stand 804 Ti Stand (requires rod stirrer)
Figure 7
Make sure that the flat side of the plug matches the marking on the socket.
Connecting a stirrer
CAUTION
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3.4 Connecting a balance

Balances are equipped with a serial RS-232 interface as a rule. To connect a balance, you require a 6.2148.030 RS-232/USB Box.
Figure 8 Connecting a balance
When a 6.2151.020 USB cable is used, then the 6.2148.030 RS-232/USB Box can be connected to the 877 Titrino plus by means of a USB hub or a
6.2151.100 adapter (see Chapter 3.5, page 11).
3 Installation
Connect the 9-pin plug of the respective balance connecting cable to the RS 232/1 connector. Consult the user manual of the balance in order to select the correct connecting cable.
The parameters for the RS-232 interface on the instrument must match those on the balance (see "Editing the COM1 settings", page 63). Addi­tionally consult the user manual of the balance.
3.5 Connecting a keyboard, printer and other USB devi­ces
The 877 Titrino plus has a USB (OTG) connector. Use the provided
6.2151.100 adapter USB MINI (OTG) - USB A for connecting USB devices as e.g. printers, keyboards or USB sticks, see the following figure.
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3.5 Connecting a keyboard, printer and other USB devices
6.2151.100
Figure 9 Connecting USB devices
CAUTION
Switch the instrument off before connecting or disconnecting a USB device or a USB stick.
The 877 Titrino plus can only recognize the device immediately after switching on.
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The following devices can be operated directly on the USB connector with the 6.2151.100 adapter:
USB sticks (for the backup or storing of methods) 6.2147.000 numerical USB keypad 6.2148.030 RS-232/USB Box (for connecting balances or for the
RS-232 remote control)
USB hub (with or without an own power supply)
The 6.2147.000 numerical USB keypad serves for comfortable numer­ical input and for navigating in the dialog. In addition, it provides two USB connectors. Connect additional USB devices to the keypad.
NOTE
Most of the USB devices need a so-called hub in order to work cor­rectly.
A USB hub is a distributor to which several USB devices can be connec­ted. USB hubs are available in specialty stores in a number of different models.
The USB (OTG) connector of the 877 Titrino plus has no such hub. The
6.2147.000 numerical USB keypad has a USB hub and two USB con­nectors.
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USB MINI (OTG)-USB
USB stick
6.2151.100
USB MINI (OTG)-USB
USB stick
Keypad
6.2147.000
6.2151.100
Printer
3 Installation
The following devices can only be connected to a 6.2147.000 numerical keypad or to a USB hub:
Printer (with USB connector, use the 6.2151.020 connecting cable) Barcode reader (with USB cable) Mouse (PC mouse with USB cable, for navigating in the dialog)
The following devices can only be connected to a USB hub:
PC keyboard (with USB cable, for the comfortable input of letters and
numbers)
Keypad with numerical keypad (with USB cable)
If you wish to connect several different instruments without own power supply, then you must possibly use a USB hub with own power
supply (self powered). The USB (OTG) connector of the 877 Titrino plus is not designed for supplying power to several devices with elevated electric­ity requirements.
Also observe the instructions in chapter 10.4, page 103.
Examples:
Figure 10
Connecting the USB stick
Figure 11 Connecting the 6.2147.000 USB keyboard with USB stick and
printer
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3.6 Connecting instruments to the remote connector

USB MINI (OTG)-USB
USB stick
USB-Hub
RS-232/USB Box
6.2148.030
6.2151.100
Printer
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Figure 12 Connecting the USB hub with USB stick, printer and the
6.2148.030 RS-232/USB Box (for connecting balances).
3.6 Connecting instruments to the remote connector
The 877 Titrino plus can be integrated in an automation system with the aid of a remote cable.
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Figure 13
Connecting a remote cable
A variety of different connecting cables are available for connecting Metrohm instruments (e.g. sample changers) (see Optional Accessories chapter).
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3.7 Attaching the exchange unit

3 Installation
Figure 14 Attaching the exchange unit
To attach the exchange unit, proceed as follows:
Slide the exchange unit from the front onto the 877 Titrino plus and
1
push all the way to the rear.
It must snap in audibly.
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4.1 Monotonic equivalence point titration (MET)

U/mV
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4 Titrations

4.1 Monotonic equivalence point titration (MET)
Monotonic equivalence point titration is a titration mode for titrations with relatively high signal fluctuations or suddenly occurring potential jumps and for slow titrations or slow-response electrodes. The reagent is added in constant volume steps. Measured value acceptance is drift-con­trolled (equilibrium titration) or after a waiting time. Equivalence points are evaluated automatically.
Figure 15
Reagent dosing for MET

4.2 Endpoint titration (SET)

Endpoint titration is a titration mode for rapid routine determinations to a preset endpoint (e.g. titrations in accordance with special norms) and titrations for which reagent overflow must be avoided. The titration termi­nation at the endpoint takes place either drift-controlled or after a waiting period. The volume dosed until the endpoint is used for calculating the content of the sample.
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t/s
EP
Continuous dosing
Initial dosing
V/mL
V/mL
U/mV
Control range
4 Titrations
Figure 16 Reagent dosing for SET
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5.1 Switching the instrument on and off

5 Operation

5.1 Switching the instrument on and off
Switching on the instrument
Proceed as follows:
Press the red [STOP] key.
1
The instrument is initialized and a system test performed. This process takes some time.
If a buret unit has been attached, then a request appears to carry
out the PREP function:
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All tubings and the cylinder are rinsed with the PREP (Preparing) function. The preparing of the buret unit is described in chapter "Preparing the buret unit (PREP)", page 44.
Confirm the message with [OK].
The display of this message can be deactivated in the system set­tings (see "PREP warning", page 53).
The main dialog is displayed:
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Switching off the instrument
The instrument is switched off with the [STOP] key. The fact that the key needs to be pressed down for an extended time prevents accidental switch off.
Proceed as follows:
Keep the red [STOP] key pressed down for at least 3 s.
1
A progress bar is displayed. If the key is released during this time, then the instrument will not be switched off.

5.2 Fundamentals of operation

5.2.1 The keypad

5 Operation
Figure 17
Keypad 877 Titrino plus
BACK Apply the input and exit the dialog.
Move the selection bar either up or down by one
line at a time. Select the character to be entered in the text editor.
Select the character to be entered in the text and
number editor. Select the individual functions in the function bar.
OK Confirm the selection.
STOP Stop an ongoing method run or a manual func-
tion. Switch the instrument on or off.
START Start a method run or a manual function.
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5.2 Fundamentals of operation

5.2.2 Structure of the dialog windows

The current dialog title is displayed on the left-hand side of the title bar. The current status of the system is displayed in the upper right-hand cor­ner:
ready The instrument is in normal status.
cond.busy The working medium is being conditioned.
cond.ok The working medium is conditioned.
busy A method has been started.
hold A method has been paused.
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Some dialogs have a so-called function bar on the bottom line. The func­tions contained therein can be selected with the arrow keys [] or [] and executed with [OK].

5.2.3 Navigating in the dialog

The selection bar is displayed in inverted style. Use the arrow keys [] and [] to move the selection bar upward or downward one line at a time. If
a dialog text is marked with "", then additional settings are available in a subordinate dialog. Use [OK] to access this dialog.
Example: System settings
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