Mettler Toledo D77, DL70ES, DL67 Operating Instructions Manual

Operating Instructions

METTLER TOLEDO

/

DL77

DL70ES

/

DL67 Titrators

S

E

L

RESET

S

E

L

EXIT

RUN

1. INSTALLATION

2. EDITOR

3. ANALYSIS

4. AUXILIARY FUNCTIONS

5. DOCUMENTATION

6. USER LEVEL

7. REMOTE CONTROL

8. Designations – Explanations – Examples

9. Error messages and malfunctions

10. Applications

11. Installation instructions, Technical data, Accessories

12. Index, Certificates & Declarations

Introduction

Safety measures

The titrators have been tested for the experiments and intended purposes documented in the
Tutorial and these Operating Instructions. However, this does not absolve you from the
responsibility of performing your own tests of the products supplied by us regarding their
suitability for the methods and purposes you intend to use them for. You should therefore
observe the following safety measures.

Measures for your protection

– Ensure that you plug the power cable supplied into a receptacle outlet that

is grounded! In the absence of grounding, a technical fault could be lethal.

– Switch the instrument off and disconnect the power cable before you open

Risk of electric

shock

the housin or change blown fuses! An electric shock could be lethal.

– Never work in an environment subject to explosion hazards! The housing

of the instrument is not gas tight (explosion hazard due to spark formation,
corrosion caused by the ingress of gases).

Risk of explosion

– Always test the titration vessel for firm seating in the titration head! If it falls

off, you could injure yourself if working with toxic titrants and solvents or
strong acids or bases.

Risk of corrosion

– When using chemicals and solvents, comply with the instructions of the

producer and the general lab safety rules! Additional safety precautions for
Karl Fischer titrations are described in Section 10.2.

Measures for operational safety

– Check the set operating voltage before you switch on the titrator (see

Section 11.1.5)! The instrument will be damaged if the operating voltage
does not match the line voltage.

Caution

– Use only fuses of the specified type if you need to change them!– Have

the instrument serviced only by METTLER TOLEDO Service!

– Always wipe off splashed liquids immediately! The instrument is not water-

proof.

– Exclude the following environmental influences:

• powerful vibrations,

• direct sunlight,

• atmospheric humidity greater than 80%,

• temperatures below 5 °C and above 40 °C,

• powerful electric or magnetic fields!

02/93 METTLER DL77/DL70ES/DL67 1

11/97

Introduction

2

METTLER DL77/DL70ES/DL67

02/93

Introduction

Introduction

The DL77, DL70 ES, and DL67 METTLER titrators are microprocessor-controlled analytical
instruments that provide accurate and reproducible results thanks to their built-in intelligence.

With these titrators, you can perform end point, equivalence point and pH-stat titrations,
measure pH/mV and temperature, and determine TAN/TBN and p/m values. With the aid of
a polarization current source, you can determine water contents by the Karl Fischer method
(>2 mg H2O/sample). You can perform conductivity measurements and conductometric
titrations with an appropriate non-Mettler unit equipped with an analog output.

All titrators have a maximum of four inputs for electrodes, two for temperature sensors and
three 24-V outputs for stirrer, pump or valve attachments. They have a maximum of four
RS232C/CL interfaces, enabling you to connect a series of peripheral instuments:

- an attached METTLER balance transfers the sample weight automatically,

- a printer records the desired results,

- a color terminal serves as a second display and can be used for remote control, or a PC/robot
can interchange data with the titrator, and

- with an attached METTLER Sample Changer, each titrator is turned into a titration system
for the automatic analysis of whole series of samples.

How the three titrators differ from each other
DL77: Two titrations can be executed simultaneously and two sample changers can be

connected. Neither the DL70ES nor the DL67 allow this.

DL77/ These titrators can control a maximum of four burette drives, the DL67 two.
DL70ES:

These instruments know the most important titrants and all METTLER sensors,
whereas the DL67 knows one titrant and one sensor.

With both titrators a maximum of 10 titration methods can be entered in a list and
processed in succession. With the DL67 one method can be entered at a time.

While a titration is running, you can develop and save a new method, or you can
enter sample data for the next titration method. This is not possible with the DL67.

02/93 METTLER DL77/DL70ES/DL67 3

Introduction

Operating concept

What information will you find where?

1. The TUTORIAL, provided with the standard equipment, will help you to overcome any
inhibitions you may have with regard to the new instrument. You will get to know the
function keys, the keypad and the display. Using a stored method for an acid-base titration,
you will perform your first analysis.

2. These Operating Instructions provide a complete description of the concept and oper-
ating characteristics of the three titrators.
The operating concept and a compilation of the key combinations follow this introduction.

3. The RS232C Interface Description, i.e., a detailed description of the communication bet-
ween titrator and computer, is provided with the standard equipment (since June, 1999).

Note: These Operating Instructions apply to software version 3.0 or 3.1.

The organization of the Operating Instructions

The organization is based on a modular principle. This allows supplementation or the inter­change of individual sections or pages: new text sections carry the date of issue (in the footer
on every page).

The operating concept of the titrator

The operation of the titrator is menu driven. What does this mean?
The titrator handles various tasks:

It stores, for instance, titrant names with the corresponding concentrations; it knows that it must
terminate the titration after an equivalence point has been found; it rinses burettes and can
provide records of stored data on an attached printer.

We call the listing of these various tasks a menu. Each task is subdivided further. If you select
a task from the main menu you are shown a new set of tasks – the submenu – from which you
can select another task. We refer to this as a menu tree when the main menu branches into
submenus and these in turn into additional submenus.

4

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02/93

Introduction

02/93 METTLER DL77/DL70ES/DL67 5

Introduction

6

METTLER DL77/DL70ES/DL67

02/93

Introduction

Key combinations

Rapid menu change with key combinations

In the Tutorial, you have already become acquainted with several key combinations which you
can employ to obtain a certain menu immediately. Using these keys, you can reduce the
number of keystrokes before and during the titrations considerably. The key combinations
consist of the index key and a letter key which must be pressed simultaneously. Key combi­nations exist to

• jump from a submenu into the main menu or from a submenu into that of another branch,
or to

• trigger commands for the burette or the printer (see below)

If you press a key combination in a submenu, the DL70 stores all changes that you have made
up to this point in the menu. The selector bar can be on any line of the menu.

Key combinations for commands

+

U

+

Y

+

L

+

P

+

C

Rinse burette (see Section 4.1.1)
Rinse tip (see Section 4.1.2)
Trigger line feed on the printer (see Section 1.8.1)
Trigger form feed on the printer (see Section 1.8.1)
The current display is printed (copied!)

Key combinations for menu change

MAIN MENU
INSTALLATION
EDITOR

+

M

ANAL YSIS A
ANALYSIS B*
AUXILIARY FUNCTIONS
DOCUMENTATION
USER LEVEL
REMOTE CONTROL

* only DL77

only if computer is installed

Installation
Titrants
Sensors

+

I

02/93 METTLER DL77/DL70ES/DL67 7

Temperature sensors
Auxiliary reagents
Auxiliary instruments
Auxiliary values
Titration stands
Peripherals
Miscellaneous

Introduction

Key combinations

+

E

Editor
Method ID
METTLER methods
User methods
New method

+

A

Method

Method

+

B

Auxiliary functions
1 Burette
2 Stirrer
3 Sensor

+

F

+

D

4 Temperature
5 Sample changer
6 Auxiliary instrument
7 Calibration temperature sensors
8 Offset adjustment sensor inputs

Documentation
Print
Data transfer
Memory copy

Method
Add*

Method
Add

A

A

B

B

*DL67: Load
A: only DL77

only DL77

only if sample changer is installed
only if temperature option has been built in

No. ID2 Wt./vol.

+

S

+

T

1/1
1/2
1/3

mV

0.0000 g

0.0000 g

0.0000 g

E –V curve

Sample data list for the current method
(example)

Display of the method function for the
current method (Titration function active)

mL

8

METTLER DL77/DL70ES/DL67

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INSTALLATION

INSTALLATION

Contents Page

1. INSTALLATION........................................................................................... 1-3

1.1 Titrants ........................................................................................................ 1-4

1.1.1 Delete........................................................................................................... 1-4

1.1.2 Modify........................................................................................................... 1-4

1.1.3 Add............................................................................................................... 1-8

1.2 Sensors ....................................................................................................... 1-9

1.2.1 Delete........................................................................................................... 1-10

1.2.2 Modify........................................................................................................... 1-10

1.2.3 Add............................................................................................................... 1-14

1.3 Temperature sensors................................................................................. 1-15

1.4 Auxiliary reagents ...................................................................................... 1-17

1.4.1 Delete........................................................................................................... 1-17

1.4.2 Modify........................................................................................................... 1-17

1.4.3 Add............................................................................................................... 1-18

1.5 Auxiliary instruments ................................................................................ 1-20

1.5.1 Delete........................................................................................................... 1-20

1.5.2 Modify........................................................................................................... 1-20

1.5.3 Add............................................................................................................... 1-21

1.6 Auxiliary values.......................................................................................... 1-23

1.7 Titration stands .......................................................................................... 1-25

1.8 Peripherals.................................................................................................. 1-28

1.8.1 Printer........................................................................................................... 1-28

1.8.2 Balance ........................................................................................................ 1-30

1.8.3 System ......................................................................................................... 1-32

1.8.4 Sample changer ........................................................................................... 1-35

02/93 METTLER DL77/DL70ES/DL67 1-1

INSTALLATION

INSTALLATION

Page

1.9 Miscellaneous............................................................................................. 1-36

1.9.1 Format date/time .......................................................................................... 1-36

1.9.2 Enter date/time ............................................................................................. 1-36

1.9.3 Language ..................................................................................................... 1-37

1.9.4 Record header ............................................................................................. 1-37

1.9.5 Titrator ID ..................................................................................................... 1-37

1.9.6 Routine level ................................................................................................ 1-38

1.9.7 Audio signal.................................................................................................. 1-39

1.9.8 Analysis parameters..................................................................................... 1-40

1-2

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INSTALLATION

INSTALLATION

1. INSTALLATION

In order to perform titrations the titrator must be acquainted with the titrants and their
concentration, the sensors with their possible unit of measurement, and the solvents that it can
dispense by means of pumps. It must know the burette drive on which the burette is located,
the input to which the sensor is connected and what output carries the stirrer. It needs the
names of the attached units such as a balance or printer in order to transfer data. In this menu
you enter and store the names of all chemical and mechanical resources: you install them.

The most common titrants, solvents and all METTLER sensors are already installed in the
titrator. Not only can you delete these resources or modify their parameters, but you also have
the possibility to install new ones.

List of resources Titrants

Sensors
Temperature sensors
Auxiliary reagents
Auxiliary instruments
Auxiliary values
Titration stands
Peripherals
Miscellaneous

Caution: All resources needed for the METTLER methods stored in the application data

base are installed accordingly. If you delete one of these, the titrator will wait until
start of titration of a METTLER method before outputting the error message that the
resource is not installed.

DL67: Only the titrant and the sensor for METTLER method M001 are stored in the DL67.

02/93 METTLER DL77/DL70ES/DL67 1-3

Titrants

INSTALLATION

1.1 Titrants

When you select this menu you receive the installed titrants with the specified parameters
concentration and burette drive. (You will find the menu tree depicted at the end of Section

1.1.2.)

NaOH 0.1 mol/L Drive 3
HCl

HClO

4

etc...

DL67: The DL67 only has stored the titrant NaOH. You can, however, add titrants to the list

(see Section 1.1.3).

If you select, for instance, NaOH the list will be masked on the right by a selection menu
containing the following commands:

0.1 mol/L Drive 3

0.1 mol/L Drive 3

Delete
Modify
Add

1.1.1 Delete

Position the selector bar on this command and confirm with RUN. The mask of the selection
menu disappears, the titrant NaOH is deleted.

Note: You can also delete a titrant directly from the list by pressing the <–> (minus) key. You

can reinstall NaOH with the command Add (see Section 1.1.3).

1.1.2 Modify

If you select this command you are shown the parameter mask of the titrant (see next page).
If you move the selector bar to one of these parameters you can modify its name or value.

Note: a. Default values are stored in the titrator for all parameters, e.g. for the concentration

of the titrant 0.1 mol/L, for the titer 1.0.

1-4

• These values will be overwritten once you have entered new ones.

• If you want to modify only one digit of a value, you must first indicate the digit with
the cursor (with → or ←) prior to entering the new one.

METTLER DL77/DL70ES/DL67

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INSTALLATION

Titrants

Note: b. With many parameters the titrator has selection or recommendation menus in which

you need only select the values or names. If a parameter has one of these menus,
each time it is selected an arrow symbol (➡) appears at the extreme right in the
middle of the display. You can either accept the value or name following the
parameter or:

in the case of Recommendation,

– overwrite directly with a new entry or
– press SEL to select a new value or name from the recommendation menu that

appears.

in the case of Selection,
– press SEL to select a new value or name from the selection menu that appears.

You cannot enter the value or name yourself.
If only two names or values are possible for a parameter, these are toggled

automatically with SEL.

Name NaOH
Concentration [mol

/L]

0.1
Titer 1.0
Burette volume 10 mL
Burette drive Drive 3
Date/time (e.g.: 07–06–1992 12:20)

1. You can overwrite the name or press SEL to call up the recommendation menu:

Recommendation menu: You can select a new titrant from the recommendation menu.

Position the selector bar on, for instance, HCl and confirm with RUN. The recommendation
menu disappears and HCl follows Name.

2. Enter the concentration [mol/L]

3. Enter the titer only if you know its value. If you determine the titer of the titrant with the

titrator, its value is entered here together with the date automatically (see

Titer

function,

Section 2.3.16).

4. Select the burette volume from the selection menu:

Selection menu: You press SEL, position the selector bar on, for instance, 5 mL in the
selection menu and confirm with RUN. The selection menu disappears and 5 mL now
follows burette volume.

5. Select the burette drive from the selection menu.

02/93 METTLER DL77/DL70ES/DL67 1-5

Titrants

INSTALLATION

DL67: It is only possible to select one of two burette drives for this titrator. If more than two

drives have been installed, the titrator will recognize each of the first two (counting from
left to right).

6. You can neither delete nor overwrite the date. It refers to the titer determination of the titrant
using the method function
(see

Titer

function, Section 2.3.16).

Titer

and is entered here together with the time automatically

Note: As soon as you change a titrant parameter, the date and time are deleted.

The titrant with the modified parameters is installed when you quit the parameter mask with
EXIT. Here, the selector bar can be positioned on any parameter, but not on the title line.If you
confirm the title line with EXIT the following selection menu appears:

Save modifications?
Yes
No

If you confirm "Yes" with RUN, the titrator stores the modified values or names.
If you confirm "No" with RUN, the old values remain in force.

Note: If you press a key combination (<index + letter>) to quit the Installation menu, the

modified parameters are stored automatically if the selector bar is positioned on a
parameter line. If it is positioned on the title line, the selection menu "Save modifications?"
appears again (see above).

1-6

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02/93

INSTALLATION

Menu tree

Titrants

Titrant
NaOH
HCl
HClO
etc.

Selection

0.1 mol/L

0.1 mol/L

4

0.1 mol/L

Drive 3
Drive 3
Drive 3

Delete
Modify
Add

The titrant
is deleted

Titrant parameters
Name
Concentration [mol/L]
Titer
Burette volume
Burette drive
Date/time

Enter new name or select
entry from recommendation
menu with SEL

Enter new concentration

NaOH

0.1

1.0
10 mL
Drive 3
(07-06-1992 12:20)

Titrant names
NaOH
HCl
HClO

4

etc.

Enter new titer or let it be
entered through titration

Select another burette
with SEL

Burette volume
1 mL
5 mL
10 mL
20 mL

Select another drive
with SEL

Burette drive
Drive 1
Drive 2
Drive 3
Drive 4

Date/time is entered only through titer determination by the titrator!

02/93 METTLER DL77/DL70ES/DL67 1-7

Titrants

INSTALLATION

1.1.3 Add

Select this command if you wish to add a titrant to the titrant list, for instance NaOH of
concentration 1.0 mol/L or with a different burette volume, or a new titrant. You can also add
a titrant directly to the list by pressing the <+> (plus) key. You are always shown the following
mask:

Name NaOH
Concentration [mol

/L]

0.1
Titer 1.0
Burette volume 10 mL
Burette drive Drive 3
Date/time 00–00–0000 00:00

1. Select the titrant from the recommendation menu or enter the one you wish to install.
Note: If you install, for example, several NaOH solutions of the same concentration, you must

provide each name with a different flag to allow the titrator to distinguish between them,
e.g. NaOH/1.

2. Enter the concentration [mol/L].

3. Enter the titer only if you know its value. If you determine the titer with the titrator, its value

together with the date is entered here automatically (see

Titer

function, Section 2.3.16).

4. Select the burette volume from the selection menu.

5. Select the burette drive from the selection menu.

6. The date together with the time for the newly installed titrant is entered here automatically

only after the titer has been determined (see

Titer

function, Section 2.3.16).

The titrant with the appropriate parameters is installed when you quit the parameter mask with
EXIT (see the appropriate description at the end of Section 1.1.2).

1-8

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INSTALLATION

Sensors

1.2 Sensors

When you select this menu you are shown the installed sensors with the specified parameters
unit of measurement and the sensor input. (You will find the menu tree depicted at the end of
Section 1.2.2.)

DG111-SC pH Sensor 1 (Combined pH electrode – aqueous medium)
DG101–SC pH Sensor 1 (Combined pH electrode for small volumes in a

small titration vessel – aqueous medium)

DG113–SC mV Sensor 1 (Combined glass electrode with movable sleeve

frit – nonaqueous medium)

DG114–SC mV Sensor 1 (Combined glass electrode with movable sleeve

frit – aqueous medium)

DG115–SC mV Sensor 1 (Combined glass electrode with sleeve frit –

aqueous medium)

DM140–SC mV Sensor 2 (Combined platinum ring electrode – redox

titrations)

DM141–SC mV Sensor 2 (Combined silver ring electrode – argentometry)
DM142 mV Sensor 1 (Double-pin platinum electrode – voltametry)
DP550 % T Sensor 2 (Phototrode – transmission measurements at

550 nm)

DP660 % T Sensor 2 (Phototrode – transmission measurements at

660 nm)

DL67: Only sensor DG111-SC is stored in the DL67. You can, however, add sensors to the

list (see Section 1.2.3).

Note: There is no need to install a reference electrode as it is part of the installed measuring

electrode at input sensor 1. The input for the reference electrode is marked (see Sec­tion 11.1.4).

If you select DG111-SC, for instance, the list is masked on the right by a selection menu
containing the following commands:

Delete
Modify
Add

02/93 METTLER DL77/DL70ES/DL67 1-9

Sensors

INSTALLATION

1.2.1 Delete

Position the selector bar on this command and confirm with RUN. The mask of the selection
menu disappears, the DG111-SC sensor is deleted.

Note: You can also delete a sensor directly from the list by pressing the <–> (minus) key. You

can reinstall the DG111-SC with the Add command (see Section 1.2.3).

1.2.2 Modify

If you select this command you are shown the parameter mask of the sensor in which you can
change the parameter values:

Name DG111-SC
Unit of measurement pH
Sensor input Sensor 1
Zero point [Unit] 7.0
Slope [mV/Unit] –59.16
Temperature [°C] 25.0
Date/time (e.g.: 02–06–1992 10:15)

1. Select the sensor name from the recommendation menu or enter the one you wish to install

in place of the DG111-SC sensor.

2. Select the unit of measurement suitable for the sensor from the selection menu. Within a

method you can later again choose between the selected unit of measurement and "mV"
in the functions Measure, Titration and pH/mV-stat (see Section 2.3.4/ 12/13).

mV: Either there is no other unit of measurement suitable for the sensor, or you

require only mV.
If you select the unit mV for a sensor, the calibration parameters zero point,
slope and temperature are ignored by the titrator.

pH: After you select pH you then enter the calibration parameters for a pH electrode

or you let the titrator do it (see notes a. and b. on page 1-12).

pM: M represents any cation. After you select pM you then enter the calibration

parameters for a pM electrode or you let the titrator do it (see notes a. and b.
on page 1-12).

pX: X represents any anion. After you select pX you then enter the calibration

parameters for a pX electrode or you let the titrator do it (see notes a. and b.
on page 1-12).

1-10

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INSTALLATION

Sensors

%T: After you select %T you then enter the calibration parameters of a phototrode

(unit of measurement: transmission, see

Operating Instructions "Phototrode"

A: After you select A you then enter the calibration parameters of a phototrode

(unit of measurement: transmission. The absorption (A = -log T) is calculated,
see

Operating Instructions "Phototrode"

).

µS/cm: After you select µS/cm you then enter the calibration parameters of the conduc-

tivity cell.

mS/cm: After you select mS/cm you then enter the calibration parameters of the conduc-

tivity cell.

Note: Conductivity measurements and conductivity titrations can be performed using a

conductometer equipped with an analog output.

3. Select the sensor input from the selection menu.

).

Notes: a. In the standard configuration of the titrator you have the sensor 1 and sensor 2 input

available. You should select the sensor 1 input for all glass electrodes as this has
the highest input resistance (see

Technical data

, Section 11.2.1)

Rear view of the titrator

.

, Section 11.1.4 and

b. For technical reasons, only the "low resistance" sensor input 2 may be selected for

phototrodes (see
Section 11.2.1)

Rear view of the titrator

.

, Section 11.1.4 and

Technical data

Caution: The RS option has an additional "low resistance" sensor input, the temperature

option an additional high resistance sensor input (see Sections 11.1.6 and 11.1.7).
Depending on the installation manner, the "low resistance" input may, for example,
be either sensor 3 or sensor 4! (See

Technical data

, Section 11.2.1).

Rear view of the titrator,

Section 11.1.4 and

4. Enter the zero point of the sensor:
The zero point of a sensor is the measured value at which it displays 0 mV potential (zero

point of electrode assembly).

• For the zero point of a pH electrode this is pH0 with unit pH.

,

• For the zero point of an ion-selective electrode this is pM0 with the unit pM, or pX0 with

the unit pX.

• The zero point of the phototrode is normally 0% T (100% T = 1000 mV).

• The zero point of a conductivity cell is normally 0 µS/cm or 0 mS/cm.

02/93 METTLER DL77/DL70ES/DL67 1-11

Sensors

INSTALLATION

5. Enter the slope of the sensor.
The slope of a sensor is the potential change in mV per unit of measurement.

• For the slope of a pH electrode the unit is: mV/pH.

• For the slope of an ion-selective electrode the unit is: mV/pM or mV/pX.

• The slope of a phototrode is normally 10 mV/ %T.

• For the slope of a conductivity cell the unit is: mV/µS*cm

-1

or mV/mS*cm-1.

6. Enter the temperature: The actual calibration temperature is either

• defined by you when starting a calibration method (see Section 3.1) or

• measured automatically if you have attached and installed a temperature sensor (see
Sections 1.3, 2.3.2 and 2.3.17).

7. You can neither delete nor overwrite the date. It refers to the calibration of the sensor using
the method function
(see

Calibration

Calibration

and is entered here together with the time automatically

function, Section 2.3.17).

Notes: a. The calibration parameter values of the titrator installed in the factory are theoretical

values for a new sensor. You have to perform a calibration of your sensor if you wish
to determine accurate values (see

Calibration

function, Section 2.3.17).

b. When a pH, pM or pX sensor is calibrated the calibration parameters (zero point,

slope, temperature) are entered here automatically.

c. As soon as you change a sensor parameter, the date and time are deleted.

Caution: Do not transfer the calibration data obtained for glass electrodes attached to sensor

input 1 (or for the temperature option sensor input) to the electrodes you attach to
sensor input 2 (or the sensor input of the RS option)! Recalibrate these sensors to
obtain correct values!

The sensor with the modified parameters is installed when you quit the parameter mask with
EXIT (see the appropriate description at the end of Section 1.1.2).

1-12

METTLER DL77/DL70ES/DL67

02/93

INSTALLATION

Menu tree

Sensors

Sensors
DG111-SC
DG101-SC
DG113-SC
DG114-SC
DG115-SC
DM140-SC
DM141-SC
DM142
DP550
DP660

pH
pH
mV
mV
mV
mV
mV
mV
%T
%T

Sensor 1
Sensor 1
Sensor 1
Sensor 1
Sensor 1
Sensor 2
Sensor 2
Sensor 1
Sensor 2
Sensor 2

Sensor parameters
Name
Unit of measurement
Sensor input
Zero point [unit]
Slope [mV/unit]
Temperature [°C]
Date/time

Enter new name or select entry from
recommendation menu with SEL

DG111-SC
pH
Sensor 1

7.0

-59.16

25.0
(02-06-1992 10:15)

Selection
Delete
Modify
Add

The sensor is
deleted

Sensor names
DG111-SC
DG101-SC
DG113-SC
etc.

Select another unit of measurement
with SEL

Select another input with SEL

Enter new zero point or let it be
entered through calibration

Enter new slope or let it be entered
through calibration

Enter new temperature

Date/time is entered only through calibration by the titrator!

Units of meas.
mV
pH
pM
etc.

Sensor inputs
Sensor 1
Sensor 2
Sensor 3
Sensor 4

02/93 METTLER DL77/DL70ES/DL67 1-13

Sensors

INSTALLATION

1.2.3 Add

Select this command if you wish to add a sensor to the sensor list, for instance a
DG111-SC sensor with different calibration parameters or a sensor not yet installed. You can
also add a sensor directly to the list by pressing the <+> (plus) key. You are always shown the
following mask:

Name DG111-SC
Unit of measurement mV
Sensor input Sensor 1
Zero point [Unit] 7.0
Slope [mV/Unit] –59.16
Temperature [°C] 25.0
Date/time 00–00–0000 00:00

1. Select the sensor name from the recommendation menu or enter the name of the sensor
you wish to install.

Note: If you install, for example, several DG111-SC sensors, you must provide each name

with a different flag to allow the titrator to distinguish between them, e.g. DG111/2.

2. Select the unit of measurement suitable for the sensor from the selection menu.

3. Select the sensor input from the selection menu.

4. Enter the zero point of the sensor.

5. Enter the slope of the sensor.

6. Enter the temperature.
(see explanation of the parameters and note under

Modify

).

7. The date together with the time for the newly installed sensor is entered here automatically
only after the sensor has been calibrated (see

Calibration

function, Section 2.3.17).

The sensor with the appropriate parameters is installed when you quit the parameter mask with
EXIT (see the appropriate description at the end of Section 1.1.2).

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INSTALLATION

Temperature sensors

1.3 Temperature sensors

When you select this menu you are shown the installed temperature sensors with the specified
parameters sensor type and sensor unit:

TEMP A Pt100 Temp 1
TEMP B Pt100 Temp 2
TEMP C Pt1000 Temp 1
TEMP D Pt1000 Temp 2

You can neither delete a temperature sensor nor add a new one to the list. You can, however,
install several Pt100 or Pt1000 at the same temperature sensor input (Temp 1 or Temp 2), for
example.

If you select TEMP A, for instance, you are shown the parameter mask of the Pt sensor in which
you can change the parameter values or names:

Name TEMP A
Sensor type Pt100
Sensor input Temp 1
Zero point [°C] 0.0
Date/Time 00–00–0000 00:00

1. You can not change the sensor name: The line will be skipped when the selector bar is
moved.

2. Select the sensor type with SEL: "Pt100" or "Pt1000" (see Section 11.1.7).

3. Select the sensor input with SEL: "Temp 1" or "Temp 2" (see Section 11.1.4).

4. Enter the zero point of the Pt sensor.
The zero point of a Pt sensor is the deviation of a measured value from a reference value,

such as 0 °C for an ice bath.

5. You can neither delete nor overwrite the date. It refers to the calibration of the Pt sensor
using the auxiliary function

Calibration temperature sensors

and is entered here together

with the time automatically (see Section 4.7).

Notes: a. The installed zero point is the theoretical value for a new Pt sensor. You have to

perform a calibration of your sensor if you wish to determine an accurate value.
When calibrating, the zero point is automatically entered here together with the date
(see auxiliary function

Calibration temperature sensors

, Section 4.7).

b. As soon as you change a parameter of the temperature sensor, the date and time

are deleted.

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Temperature sensors

INSTALLATION

The Pt sensor with the modified parameters is installed when you quit the parameter mask with
EXIT (see the appropriate description at the end of Section 1.1.2).

Menu tree

Temperature sensors
TEMP A
TEMP B
TEMP C
TEMP D

Pt100
Pt100
Pt1000
Pt1000

Temp 1
Temp 2
Temp 1
Temp 2

Temperature sensors
Name
Sensor type
Sensor input
Zero point [°C]
Date/time

The name cannot be changed

Select the other type with SEL: Pt1000

Select the other input with SEL: Temp 2

Enter new zero point or let it be entered
through calibration!

TEMP A
Pt100
Temp 1
0
00-00-0000 00:00

1-16

Date/time is entered only through
zero-point calibration by the titrator

METTLER DL77/DL70ES/DL67

02/93

INSTALLATION

Auxiliary reagents

1.4 Auxiliary reagents

When you select this menu you receive the installed auxiliary reagents with the specified
parameters dispensing rate and auxiliary output. An auxiliary reagent is a solvent that is
dispensed using a time-controlled device, e.g. a diaphragm pump or an electromagnetic valve.
(You will find the representation of the menu tree at the end of Section 1.4.3).

H2O 250 mL/min Aux.2
CH3OH 250 mL/min Aux.2
CHCl

3

etc.

DL67: Only auxiliary reagent H2O is stored in the DL67. You can, however, add auxiliary rea-

gents to the the list (see Section 1.4.3).

If you select H2O, for instance, the list is masked on the right by a selection menu containing
the following commands:

250 mL/min Aux.2

Delete
Modify
Add

1.4.1 Delete

Position the selector bar on this command and confirm with RUN. The mask of the selection
menu disappears, the auxiliary reagent H2O is deleted.

Note: You can also delete an auxiliary reagent directly from the list by pressing the <–> (minus)

key. You can reinstall H2O with the command Add (see Section 1.4.3).

1.4.2 Modify

If you select this command you are shown the parameter mask of the auxiliary reagent in which
you can change the parameter values:

Name H2O
Dispensing rate [mL/min] 250
Auxiliary output Aux.2

1. Select the name of the auxiliary reagent from the recommendation menu or enter the name
of the reagent you wish to install in place of H2O.

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Auxiliary reagents

INSTALLATION

2. Enter the dispensing rate [mL/min] of the device.
Notes: a. The titrator uses the dispensing rate to calculate the volume to be dispensed for

time-controlled pumps or electromagnetic valves (see functions Pump and Rinse,
Sections 2.3.8 and 2.3.9).

b. The dispensing rate of each device must be determined experimentally in advance

for each solvent:

– Add the particular solvent using the dispensing device to a measuring cylinder

within 1 minute (stopwatch) and note the volume.
– Repeat this procedure for, e.g. periods of 20, 30 and 40 seconds.
– Use the different volumes to calculate the mean value per minute and enter this

value.

3. Select the auxiliary output from the selection menu.
Note: The titrator has three auxiliary outputs (Aux. 1, 2 and 3). One auxiliary output of the

titrator is normally assigned to the stirrer, e.g. Aux. 1 (see Section 1.7). You should thus
select only Aux. 2 and/or Aux. 3 for this auxiliary reagent (see

Technical data

, Section

11.2.2).
If you have attached the sample changer (ST20A or ST20), this unit offers you two addi­tional outputs called "RINSE" and "DOSE".

The auxiliary reagent with the modified parameters is installed when you quit the parameter
mask with EXIT (see the appropriate description at the end of Section 1.1.2).

1.4.3 Add

Select this command when you wish to add an auxiliary reagent to the list. You can also add
an auxiliary reagent directly to the list by pressing the <+> (plus) key. You are always shown
the following mask:

Name H2O
Dispensing rate [mL/min] 250
Auxiliary output Aux.2

1. Select the name from the recommendation menu or enter the reagent you wish to install.
Note: If you install several auxiliary reagents with the same name, you must provide each one

with a different flag to allow the titrator to distinguish between them, e.g. H2O/2.

2. Enter the dispensing rate [mL/min] of the device.

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