Sartorius Docu-pH,Docu-pH+ Operation Manual

Operation Manual

Sartorius Docu-pH

Meter

, Docu-pH

+

Meter

Docu-pH, Docu-pH+, pH/mV Meter

Français – page xx

Español – page xx

Italiano – page xx

2

Contents

3 Contents
4 Intended Use
5 Warning and Safety Information
6 General View of the pH Meter

7 Getting Started
7 Equipment Supplied
7 Connecting the Equipment to AC Power
9 Installing Electrodes

12 Default Settings (Setup Menu)
12 Example: Selecting the Language
13 Parameter Settings (Overview)

15 Calibration (Adjustment)
15 Calibration for pH Measurement
18 Checking the Relative Millivolt Mode
19 Deleting Calibration Data
20 Docu-pH

+

Meter

Model:

Calibration with Cal Reminder

21 Operating the Meter: Measurement
21 ATC Probe
21 Lock Function
21 Fast Mode (Shorter Measurement Time)
22 Measuring the pH
22 Measuring Redox Potential
23 Docu-pH

+

Meter

Model: Saving Measured Data

26 Electrode with DocuClip

®

28 Interpreting Calibration Curves
29 Temperature Compensation
30 Docu-pH

+

Meter

Model: Data Output

31 Docu-pH

+

Meter

Model: Data Interface

32 Error Messages
33 Care and Maintenance
33 Recycling Instructions

34 Overview
34 Meter Specifications
35 Accessories
36 Declaration of Conformity

3

Intended Use

The Docu-pH

Meter

is a meter for measur­ing pH/mV and temperature. The fol­lowing measuring ranges are covered:

– pH range: -2.000 to 20.000
– mV measuring range: -2,000 to +2,000
– Temperature range: –5 to +105C°

The pH meters simplify and speed up
routine procedures thanks to their:

– Automatic electrode recognition

– Simple operation

– Rugged and sturdy construction

– Easy to calibrate with 1, 2 or 3 calibra-

tion points

– Automatic buffer recognition

– Automatic electrode test during calibra-

tion

– Automatic temperature compensation

– Clear readout with easy-to-understand

symbols and LCD

– Intuitive menu controls with plain-lan-

guage instructions via LCD and softkeys

– Electrode operation with DocuClip

®

:

Previous calibrations are traceable

– Docu-pH

+

Meter

: Serial interface for data

transfer to PC or printer

– Docu-pH

+

Meter

:

Data storage capacity: 500 datasets

Symbols

The following symbols are used in
these instructions:

§ indicates required steps

$ indicates required steps, but only

under certain conditions

> describes what happens after you

perform a certain step

– indicates an item in a list

! indicates a hazard

Conventions Used in This Operation
Manual

– The pictures in this Operation Manual

are based on the “Docu-pH

Meter

”
model. On the other models, some
display readouts and printouts may
differ slightly from the ones shown.
Any differences that impact opera­tion of the meter will be explained.

Hotline for Technical Applications
Advice

Phone: [phone]
Fax: [phone]

4

Warning and Safety Information

Your pH/mV meter complies with the
European Council Directives as well as
international regulations and standards
for electrical equipment, electromagnetic
compatibility, and the stipulated safety
requirements. Improper use or handling,
however, can result in damage and/or
injury.

§ To prevent damage to the equipment,

read this Operation Manual thoroughly
before using your pH/mV meter.
Keep these instructions in a safe place.
Please observe the following instructions
to ensure safe and reliable operation of
your pH/mV meter.

Designated Use

– Designated use of the pH/mV meter is

exclusively for measuring pH and milli­volt values in a laboratory environment.
Any use above and beyond this is
considered non-intended use.

Operational Safety

!Do not use this equipment in potentially

explosive atmospheres.

!If you use electrical equipment in instal-

lations and under ambient conditions
requiring higher safety standards, you
must comply with the provisions as
specified in the applicable regulations
for installation in your country.

!If you use an AC adapter, make sure

the voltage rating printed on the AC
adapter is identical to your local line
voltage.

– If you transport your pH/mV meter

from a cold to a warm environment,
condensation may occur and your
pH/mV meter may malfunction. In cases
like this, allow the meter’s temperature
to reach the room temperature prior
to using it again.

– Use Sartorius accessories, as these are

optimally designed for use with your
pH/mV meter.

– Calibration:

The temperature dependency for some
buffer solutions and DIN/NIST is saved
in your pH/mV meter. Automatic tem­perature compensation is only accurate
if the stored buffers are used.

– Installation instructions:

The operator shall be responsible for
any modifications to Sartorius equip­ment and must check and, if necessary,
correct these modifications. On request,
Sartorius will provide information on
the minimum operating specifications
(in accordance with the standards listed
above for defined immunity to interfer­ence).

Protection ratings for the housing:
– This meter complies with IP43
– AC adapter complies with IP20

– Only clean the meter as described in the

cleaning instructions: see the chapter

entitled “Care and Maintenance.”

$ If you have any problems with your

pH/mV meter:

contact your local Sartorius office,

dealer or service center.

5

General View of the pH Meter

Front view:

Back panel:

6

2

3

4

1

7

5

6

89

10

11

12

1 LCD
2 Softkeys
3 Mounting for electrode

holding arm

4 Only for the Docu-pH

+

Meter

:

z key: Print/Save

5 e key: On/off
6 Jack for ATC probe
7 Female connector for

“intelligent” DocuClip

®

electrode with automatic
recognition capability

8 BNC connector for pH or

ORP (redox) electrode

9 Power jack for AC adapter

10 Only with the Docu-

pH

+

Meter

: Serial interface

11 m key: Access to

Settings

12 Q key: Calibration

7

Getting Started

Storage and Shipping Conditions

Do not expose the pH/mV meter unnecessarily
to extreme temperatures, moisture, shocks, blows
or vibration.

Unpacking the pH/mV Meter

§ After unpacking the pH meter, please check

it immediately for any visible damage.

$ If any sign of damage is visible, proceed as directed

in the chapter entitled “Care and Maintenance,”
under the section on “Safety Inspection.”
It is a good idea to save the box and all parts of the
packaging until you have successfully installed your
portable meter. Only the original packaging provides
the best protection for shipment

. Before packing

your portable meter, unplug all connected cables
to prevent damage.

Equipment Supplied

The equipment supplied includes the components

listed below:
– pH meter
– AC adapter
– Electrode holding arm
– Technical buffers; pH = 4.00 and 7.00 at 25°C:

One capsule each for producing 100 ml of buffer

solution; pH = 4.00 ml and pH= 7.00
$ The pH/mV meter is also available in sets (including

electrode/DocuClip

®

). For more information, please

contact your local dealer or Sartorius directly.

Connecting the Equipment to AC Power

$ Use only the original Sartorius power adapter

supplied:

In Europe: 102 078.1.

This AC power adapter has protection rating IP20 in

accordance with the European standard EN 60529.

§ Plug the AC adapter into the power jack.

§ Attach the electrode holding arm

$ Position the electrode arm holder on the left,

if necessary.

§ Unscrew the 2 screws on the bottom of the pH/mV

meter.

§ Position the black plate with the mounting on the

other side.

§ Use the two screws to secure the plate back into

place.

8

Installing Electrodes

You can use the following electrodes with the meter:
– pH combination electrode with BNC connector
– Separate 2.5 mm phone plug for ATC probe
– Ion-selective electrode or ORP (redox) electrode with

BNC connector
– Sartorius electrodes with DocuClip

®

– The Docu-pH

Meter

automatically recognizes the types
of the ACT probes at the temperatures listed below:
– NCT10 kohm: +14°C to 76°C
– NCT30 kohm: –5°C to 40°C
– PT1000: 4°C to 105°C

Installation:

1. Remove the protective cover from the electrode.

2. Prior to first use of the pH electrode, soak it
overnight in an electrode filling solution or electrode
storage solution (3 mol/L KCl solution).

9

3. Check the pH/mV meter for correct functioning
as follows:
Connect the shorting cap to the BNC input.
Select mV mode and record the mV value:
Press the mV softkey, if necessary.
Make sure the portable meter is in mV mode.
If the mV value is 0 ± 0.3, the meter is functioning
correctly. Note that the long-term drift specified for
this portable meter is 0.1 mV/month since the most
recent calibration.

§ Connect the electrode to the input connector (1)
on the meter (push in and twist to lock).
For accurate measurements, you can connect an
additional ATC probe to the ATC port (2).
Female connector for Sartorius DocuClip

®

(3):

Automatic electrode recognition, automatic
documentation and storage of calibration data.

4. Rinse and blot-dry electrodes between measure­ments (do not wipe). Rinse electrodes with distilled
water, deionized water, or some of the next test
solution.

10

11

5. Store pH electrodes in KCl solution (3 mol/L concen­tration). Always leave the filling hole open when in
use and closed when the electrode is in storage.
Refill with filling solution when the internal solution
drops to 1 inch (approx. 25 mm) below the filling
hole.

!Equipment Supplied: Docu-pH..|P12... and ...|P20...

and ...|P23...:
The electrode supplied is a low-maintenance
gel-filled electrode that cannot be refilled.

Default Settings (Setup Menu)

Intended Use

Configuration of the pH meter, i.e. adapting to user requirements by selecting predefined
parameters from a menu.

The Setup menu is divided Language Selection

into the items: There are 5 languages available
– Calibration functions for displaying information:
– Lock function – English (factory setting)
– Fast mode – German (Deutsch)
– Settings – French (Français)
– Docu-pH+ only: data memory – Spanish (Español)

– Italian (Italiano)

Example: Selecting the Language “French”

Step Press key Display

1. Turn meter on, if required e

2. Select default m

3.

Select setup Press q softkey repeatedly,

and confirm

O softkey

4.

Confirm language O softkey

5. Select “French (Francais)” Press twice or repeatedly,
and confirm as needed

q softkey,

OK softkey

6. Exit the menu and save Press

o softkey repeatedly,

oo softkey

12

Parameter Settings (Overview)

> Factory setting; √ User setting

= Setting and function only apply to Docu-pH

+

Meter

Menu

Data Display stored
memory data

Order data > Memory number
by ... ID Number

mV
Temperature

Memory Yes
Clear > No

Print data Yes

>No

Save interval Minutes: 0 0

Seconds: 0 0

Calibration pH Calibration dataset Slope
functions Zero point

Buffer

Cal reminder Days: 00

Hours: 00

Calibration Yes
Clear > No

Select buffer set 1.68 4.01 6.86 ..

4 7 10
2 4 7 10 12

Data DocuClip

®

(electrode connected)

mV Calibration dataset mV zero point

Calibration interval Days: 00

Hours: 00

Calibration Yes
Clear > No

Data DocuClip

®

(electrode connected)

More See next page
setting
options

13

> Factory setting; √ User setting

Menu = Setting and function only with Docu-pH

+

Meter

Settings Date, > Standard format

Time U.S. format
Interface Baud rate 1200

2400
4800

> 9600

19200

Parity > None

Mark
Space
Odd
Even

Stop bits > 1 Stop bit

2 Stop bits

Handshake > Hardware

Software

Number > 7 bits
Databits 8 bits

Language > English

Deutsch
Français
Español
Italiano

Temp. > °Celsius
units °Fahrenheit

Kelvin

Resolution 0.1 pH | 1 mV
(depends on > 0.01 pH | 0.1 mV
pH or mV) 0.001 pH

Factory Yes
setting > No

Lock On
function > Off
(Static display)

Fast mode On
(Shorter > Off
measuring time)

14

Calibration (Adjustment)

Intended Use

Because electrodes vary in their response,
you must calibrate (standardize) your
pH/mV meter and electrode to compensate
for electrode variation. The more fre­quently you calibrate, the more accurate
your measurements.
Note on usage of the terms “standardize”,
“calibration” and “adjustment”: The pH
meter performs adjustments. In pH meter
jargon, however, one refers to “calibration”
or “standardization” instead of “adjust­ment”.

Preparation

Calibrate the meter and electrode using at
least two buffers. The buffers should be in
the range of the minimum and maximum
pH values to be expected for the samples.

Printing Out Calibration Results

Only the most current calibration result can
be printed out.

Procedure:

1) Menu: Calibration functions:
Load calibration dataset
(see also Chapter “Default Settings”)

2) Then print out the calibration result by
pressing the z key.

ATC Probe

Calibration can be carried out with or
without an ATC probe. If an ATC probe
is connected, the meter adjusts continu­ally for temperature during calibration

.

In this case, the pH value of the buffer
at the current temperature is taken into
account when calculating the slope of
the electrode.
When calibrating without an ATC probe,
the current temperature of each

buffer

solution must be entered manually:

1) Determining the current temperature
using a thermometer.

2) Start temperature entry:
Softkey

Temp

3) Set temperature value:
Softkey

q, softkey Q

4) Save temp value: Softkey

OK

15

Calibration for pH Measurement

Step Press key Display

1. If required, turn on meter e

2. Immerse the electrode in
a standard solution.
Stir gently.
Allow the electrode to reach
a stable value on the display.

3. Display current buffer set
and modify if required: m

16

Step Press key Display

4. Confirm calibration
functions and then pH 2+

O softkey

5. Select buffer set and 2+

q softkey,

confirm

O softkey

6. Change buffer set if required Press

q softkey

and confirm repeatedly; press

OK softkey once

7. Exit the menu and save press

o softkey

repeatedly,

oo softkey

8. Select Calibration Q

9. Start calibration with Press

first buffer

Start softkey

Calibration running ...:
The meter recognizes
the buffer automatically
from the selected set. Once the
signal stabilizes, the calibration
result is stored automatically.
The old calibration data is
automatically overwritten.

Cal. Functions
Cal. Record

Erase Cal

Select Buffer Set

Select Buffer Set

Calibration

Buffer 1

Bufferset:

Cancel

in progress ...

Cancel

Calibration

Buffer 2

Bufferset:

Cancel

End

Step Press key Display

10. Calibrate with a 2nd buffer:
Immerse the electrode in the second
buffer solution.

11. Start calibration
with second buffer

Start softkey

Carry out a 3-point calibration:
Continue, if required, with step 10:
Standardize with a 3rd buffer

12. End 2-point calibration

End softkey

The calibration result is displayed
(electrode slope, etc.).

13. Further calibration data

q softkey
Q softkey

14. Perform pH measurement

o softkey

17

Calibration

Cancel

Cal. Results

Slope1

Offset

Cal. Results
Buffer 2

Calibration

Buffer 3

Bufferset:

Cancel

End

Checking the Relative Millivolt Mode

Step Press key Display

1. If required, turn on meter e

2. Immerse the redox electrode
in a standard solution.
Stir gently.
Allow the electrode
to reach a stable value.

3. Toggle to the millivolt
measurement

mV softkey

4. Select calibration Q

5. Start calibration

Start softkey

Calibration running ...:
When the signal has stabilized:
The meter automatically stores
the measured value. The current
absolute mV value becomes zero
relative millivolts.

18

Cancel

mV Calibration

Deleting Calibration Data

Intended Use

Example: Here, delete calibration of the pH measurement
pH measurement: measuring at default settings
Redox potential: Delete the mV offset and return to the absolute mV mode.

Step Press key Display

1. Activate menu m

2. Confirm calibration Press q softkey;
functions and then pH if necessary press

O softkey repeatedly

3. Select “Clear”

q softkey,

and confirm

O softkey

4. Delete: select “Yes” and

q softkey,

confirm

OK softkey

19

Cal. Functions
Cal. Record

Erase Cal

Select Buffer Set

Erase Cal.
Yes
>No

Docu-pH

+

Meter

Model: Calibration with Cal Reminder

Intended Use

In the Setup Menu, a calibration reminder can be programmed as a reminder of when
electrode calibration should be repeated.

Step Press key Display

1. Activate menu m

2. Confirm calibration Press

q softkey

functions and then pH If necessary, press

O softkey repeatedly

3. Select “Cal reminder”

q softkey,

and confirm

O softkey

4. Set Cal reminder

q, O softkeys

5. Confirm Cal reminder

OK softkey

6. Exit the menu

o, oo softkeys

> Docu-pH+automatically displays

“Calibration” after the Cal
reminder has been overwritten.

> When a calibration interval has

expired, the following values will
appearwith an exclamation mark:
– Current measurements
– Measurements in data memory
– Measurements on the printout

20

Cal. Functions
Cal. Record
Cal. Reminder
Erase Cal.
Select Buffer Set
DocuClip Data

Cal. Reminder

Days Hours

Calibration

Buffer 1

Bufferset

Cancel

21

Operating the Meter: Measurement

Preparation

§ To select measuring mode: Press softkey
pH or mV.

!Improperly standardized electrodes

yield inaccurate measurements.
Perform calibration regularly prior to
measurement.

$ Temper buffer or buffer solutions or

measure current temperature, if the
measurement is performed without an
ATC probe.

ATC Probe

– Measurements can be performed with

and without an ATC probe.

– The Docu-pH

Meter

detects the following
type of ATC probes automatically:
– NCT10 kohm: +14°C to 76°C
– NCT30 kohm: –5°C to 40°C
– PT1000: 4°C to 105°C

!It is imperative that you measure the

temperature to achieve accurate pH
measurements. When measuring with­out an ATC probe, enter the current
temperature manually:

1) Determine the current temperature
using a thermometer.

2) Start temperature entry:
Softkey

Temp

3) Set temperature value:
Softkey

q, softkey Q

3) Save temperature value:
Softkey

OK

Lock Function

– The lock function freezes the value

in the display. Once the stability
conditions have been met, the value
is displayed statically (Symbol: “ “)
Deactivate lock function:
Press Softkey

Unlock

Activate function: see chapter entitled
“Default Settings.”

Fast Mode (Shorter Measurement
Time)

– The fast mode reduces the measuring

time by using a lower stability criterion.
Activate function: see chapter entitled
“Default Settings.”

22

Measuring the pH

Step Press key Display

1. If required, turn on meter. e

> First the Sartorius logo appears,

then the meter information.

2. Immerse the electrode in
the medium to be measured.
Stir gently. The pH appears
on the LCD.

Measuring Redox Potential

Millivolt measurement is used in electrode diagnostics, titration, and in measuring oxida­tion/reduction (redox) potential (ORP). ORP measurements indicate the oxidizing or reducing
capacity of a solution. You can use ORP potential values to monitor and control solutions
that require a defined level of oxidants or reductants.

Step Press key Display

1. If required, turn on meter e

> First, the Sartorius logo appears,

then the meter information.

2. Toggle to the millivolt

mV or

measurement.

rel mV softkey

3. Immerse the electrode in
the medium to be measured.
Stir gently

.

Allow the electrode
to reach a stable value.

Docu-pH

+

Meter

Model: Saving Measured Data

Features

– 500 data records can be stored in the nonvolatile memory.
– 21 CFR Part 11: Docu-pH

Meter

and DocuClip®have been developed for use in quality

management systems (for example, GLP, ISO 17025, 21 CFR Part 11).
– Sample ID: Input a six-digit number for each dataset.
– Set logging interval: allows you to enter the time interval for automatic data logging

with a calibration reminder between 1 seconds and 99 minutes in the Setup Menu.
– Allows you to display and print out data records.
– Parallel to data logging, the data are always printed out on an interfaced printer.
– Data memory display and settings: see chapter “Default Settings”

Step Press key Display

1. If required, turn on meter e

> First, the Sartorius logo appears,

then the meter information

2. If required, delete old data: m,

O softkey,

Menu: data memory: repeatedly press
delete memory

q softkey

3. Start saving to data z

memory

4. If required, change sample ID

ID softkey

5. Change 6-digit number Repeatedly press

Q softkey,
O softkey

6. Save changed sample ID

OK softkey

23

Stable

Step Press key Display /Printout

7. Log measurement to data memory z

. . . . . . . . . . .

and printout No: 4 Stable

pH: 6.65

´C: 21.5 ATC

D/T: 20.05.05 08:53
ID: 135933
CAL: 19.05.05 11:52

8. If required, store further z

measurements

9. View various measurements m, press

in memory:

O softkey twice

Menu: data memory:
Display stored data

10. If required, sort and filter data: m,

Menu: data memory:

O softkey,

Order data by ...

q, O softkey

11. If the memory is full:
Confirm “Overwrite data”

OK softkey

24

Confirm Overwrite

Cancel

Saving Measured Data with Calibration Reminder

Step Press key Display

1. If required, delete old data: m,

Menu: data memory:

O softkey,

memory delete

q softkey

2. Change default setting: Menu: m,

Data memory: Time interval

O softkey , repeatedly

for data logging press

q, O softkeys

3. Set time interval for data logging

q, O softkeys

4. Confirm time interval

OK softkey

for data logging

5. Exit Menu

o, oo softkeys

6. Start data logging

LogOn softkey

> Data is logged according to the

preset calibration reminder.

7. End data logging

LogOff softkey

8 View various measurements m,

in memory 2+ softkey

O

9. If required, sort and filter data: m,

Menu: data memory: O softkey,
Order data by...

q, O softkey

25

Data Memory
Recall
Select Filter
Clear Data Memory
Print Data Memory

Data Log Interval

Data Log Interval

Minutes Seconds

Data Logger Active

Free Sets

Data Logger Active

Free Sets

Electrode with DocuClip

®

Intended Use

DocuClip

®

performs the following functions:

– The Sartorius “Docu-pH

Meter

” automatically recog­nizes any connected electrode and stores the current
calibration value from the DocuClip

®

.

– Permanently stores the serial number and initial

calibration data of an electrode.

– Displays 4 calibration data records via Docu-pH

Meter

.

– Sartorius PY-P...DOC electrode models:

Autom. stores the serial number of the connected
electrode

– Product name
– Type of electrode
– Calibration data logging

Usage

– DocuClip

®

communicates with the Sartorius

Docu-pH

Meter

.

– DocuClip

®

can be used with just about all electro­chemical sensors, such as all pH electrodes that can
be connected to the Docu-pH

Meter

.

– DocuClip

®

is irreversibly fastened to the cable of the
sensor.

– DocuClip

®

is preformatted; easy-to-understand
user guidance prompts in the Docu-pH+enable the
user to intuitively perform initialization and initial
calibration.

Using Sartorius electrodes with DocuClip

®

(PY-P...DOC):

– The factory-set initial calibration is displayed as the

last of the calibration values and cannot be over­written.

Using DocuClip

®

with any type of electrode:

– Installing DocuClip

®

: If no calibration data are avail­able, Docu-pH+ prompts the user to manually enter
an electrode number and the initial calibration data.
The initial calibration value will be displayed as the
last of the calibration values and cannot be
overwritten.

26

The following data are stored permanently in DocuClip®:
– Initial calibration including date and time
– pH and voltage in mV
– Nominal values of the buffers used
– Serial number of Docu-pH

Meter

– Serial number of the electrode
– Temperature

§ View data of installed electrode/DocuClip

®

:

See Setup-Menu: Calibration functions: pH/mV: Data DocuClip

®

Enter serial number of the Electrode on Docu-pH+:

Step Press key Display

1. Connect DocuClip

®

2. Start “Serial number input” Start softkey

3. Set “Electrode number” (S/N) Repeatedly
press Q softkey,

O softkey

4. Confirm “Electrode number”

OK softkey

!Initial calibration: Please work

with particular care. The initial
calibration documents the degree
of effectiveness of the new electrode.
This calibration is the reference point
for the later analysis whenever there
is a change in performance.

27

Initial Calibration

Input
Serial No.

Cancel

Initial Calibration

Input
Electrode No.

Calibration

Buffer 1

Bufferset:

Cancel

Interpreting Calibration Curves

This depends on the chemical composition and temperature of the samples that are measured
regularly and can strongly affect how the efficacy of the electrode slope declines due to
aging of the electrode’s glass membrane. This information therefore provides clues that have
to be interpreted taking into account the true situation.

Situation Cause: Measure

Virtually constant The electrode has hardly The calibration interval can be
calibration results been subjected to increased.
over all four logged the effects of aging.
calibrations.

A constant Normal aging process Possibly shorten the calibration
reduction in slope of electrode. interval to always measure with
or zero point drift. current data.

A constant and Aging of the electrode Adhere to shorter calibration
strong reduction in slope can be accelerated by intervals to always measure with
and/or zero point drift in extremely acidic/basic current data. If the lifetime of
one direction. samples and/or the electrode is too short:

high temperatures. If appropriate, check whether the

electrode is suited for the samples
to be measured and the
measuring conditions.

An abruptly sharp Impure electrolyte, Replace electrolyte, clean
drop in slope compared to dirty membrane membrane (see electrode
last calibration or defective electrode. operation manual),

replace electrode

Strong fluctuations Measuring conditions If required, use special for
among calibration often vary greatly electrodes different measuring
results without (e.g. very hot or conditions (see also electrode
any identifiable trend. very acidic/alkaline operation manual).

media to be measured.

Strong fluctuations Fiber junction clogged Clean the electrode
in the zero point without (see electrode operation manual)
any identifiable trend If required, check whether the

electrode type used is suitable
for the sample.

After a constant Previous calibration Recalibrate because previous
reduction in slope, was incorrect. calibration was incorrect.
an increase occurs Cleaning or regeneration Document cleaning/

improved the performance regeneration.
of the electrode.

28

Temperature Compensation

!Note: The temperature is compensated automatically

only if an ATC probe is connected.

Temperature has two major effects on the results:

1. Temperature affects buffer pH values.
The values are usually given on the buffer label.
Most technical buffers correspond to the values
listed in the table shown here on the left.

When you perform calibration in the pH mode,
the pH value is adjusted to the current value for the
current temperature.

For example, if the buffer has a pH of 7.00 at 25°C
and the current buffer temperature is 20°C, the
portable meter calibrates the buffer to pH 7.02.

2. Temperature affects electrode efficiency.
The theoretical voltage change per pH unit – the
so-called Nernst factor – is approximately 59.17
mV/∆pH at 25°C. This value changes, however,
as the temperature changes. The meter compensates
for this effect by calculating the pH measurements
based on the measured temperatures and the
corresponding Nernst factors (for example,

58.16 mV/∆pH at 20°C).

29

Standard Buffers:

pH 4.00 pH 7.00 pH 10.00
0°C 4.005 7.13 10.34
5°C 4.003 7.10 10.26
10°C 4.001 7.07 10.19
15°C 4.002 7.05 10.12
20°C 4.003 7.02 10.06
25°C 4.008 7.00 10.00
30°C 4.010 6.99 9.94
35°C 4.020 6.98 9.90
40°C 4.030 6.97 9.85
50°C 4.061 6.97 9.78

Docu-pH

+

Meter

Model: Data Output

Print Data Log

Intended use

For printing out measurements, calibration data and ID codes in accordance with the
requirements of quality management systems.

Preparation:

! Switch off numerator on the optional Sartorius printer.

The data log in the pH mode can include the following lines:

. . . . . . . . . . .

. Dotted line

Blank line

No: 4 Stable Consecutive number and measurement status
pH: 6.63 pH
mV: If required, mV in the mV mode
´C: 25.0 MTC Temperature is set manually here
D/T: 20.05.05 11:53 Date and time
ID: 135933 Sample ID, entered by user
CAL: 19.05.05 08:52 Date and time of the calibration

(forms the basis for calculating the pH)

The data log for calibration results:

. . . . . . . . . . . . Dotted line

Blank line

Cal. Record
Sartorius Docu-pH+Meter Instrument number
S/N: 1234567800 Docu-pH

Meter

serial number

pH Electrode PY-P12DOC Type of electrode

S/N: A044805002 Serial number of the electrode

20.05.05 11:56 Date and time of calibration end
S1: 97.2 % Slope 1 (between buffer 1 and buffer 2)
S2: 97.1 % Slope 2 (between buffer 2 and buffer 3)
Offset : -9.1 mV Zero point in mV

(= deviation ... at pH = 7.00)

B1: 1.68 Nominal value of buffer 1 at 25°C
+310.8 mV +25.0 ´C Voltage and temperature of buffer 1
B2: 6.86 Nominal value of buffer 2 at 25°C
+0.1 mV +25.0 ´C Voltage and temperature of buffer 2
Calibration OK Calibration status

Data log from memory identifiable in line:
ID: 135933 memory Sample ID and memory printout

30

Docu-pH

+

Meter

Model: Data Interface

Intended Use

The Docu-pH

+

Meter

comes equipped with
an interface port for connection to a
computer or Sartorius printer.

Available Features

– Interface type: serial interface
– Operating mode: unidirectional
– RS232
– Transmission rate:

1200, 2400, 4800, 9600, 19200 baud

– Parity: odd, even, none, mark, space
– Character format: 7-/8-bit ASCII, parity,

1 or 2 stopbits

– Handshake:

2-wire interface: Software (XON/XOFF)
4-wire interface: Hardware (CTS/DTR­none)

– Data output format: 24 characters

Female Interface Connector:

– 9-pin D-subminiature DB9 connector

with screw attachment for direct con­nection to a computer or an optional
Sartorius data printer.

Pin Assignment:

Pin 1: Not connected
Pin 2: Serial data input (RxD)
Pin 3: Serial data output (TxD)
Pin 4: Data Terminal Ready (DTR)
Pin 5: Signal GND
Pin 6: Not connected
Pin 7: Not connected
Pin 8: CTS
Pin 9: Not connected

!No other pins may be assigned in the

Docu-pH

+

Meter

!

6

5

1

9

31

Cabling Diagram

Diagram for interfacing a computer to the Docu-pH

+

Meter

using the RS232C/V24 standard

and cables up to 15 m (~50 ft.) long

pH meter, 9-pin Computer, 9-pin
TxD 3 2
RxD 2 3
CTS 8 4
DTR 4 8
GND 5 5

Most Common Errors:

– The baud rates between the Docu-pH

+

Meter

and the computer/printer are different.
– The parity or stop bits are not set in the computer properly
– The pins in the cable are not properly configured.

Error Messages

If the meter displays a calibration error:
this indicates an error in the electrode reaction.
If this is displayed during calibration, this means
the electrode shows under 90% or over 105% of the
correct slope according to the Nernst equation.

The “Error” message can mean one of the following:
– A bad electrode
– One or more contaminated or expired buffer(s)
– Wrong buffer selected
– mV offset greater than |30|mV

Testing a pH electrode:

§ Immerse the electrode in a good neutral pH 7 buffer.

§ Access mV mode: Press softkey mV

> Record the measured value
$ Make sure the portable meter is in the mV mode and

not in the relative mV mode (rel. MV). Repeat these

steps with basic or acidic buffers. At a temperature

of approx. 25°C, the electrode signal should be

within the limits shown here:

32

Zero point at Slope Cause Solution
pH = 7.00

1)

Between –30 mV 53…62 mV/∆pH Electrode OK
and +30 mV 90...105 % of the

theoretical value

Between < 10 mV/

∆pH Glass membrane Replace electrode

–55...–65 mV or < 17 % of the ruptured
+55...65 mV theoretical value

< –30 mV and 53…62 mV/

∆pH Wrong or Replace electrolyte.

> +30 mV 90...105 % of the contaminated Not possible with gel-

theoretical value electrolyte filled electrodes

– here: replace electrode.

Between –30 mV 15…50 mV/

∆pH Membrane aged Regenerate membrane

and +30 mV 25...85 % of the (see manual of the electrode

theoretical value or replace electrode).

< –30 mV and 15…50 mV/

∆pH Membrane Clean electrode carefully

> +30 mV 25...85 % of the or junction dirty (see electrode manual).

theoretical value
> 62 mV/∆pH Buffer error Throw out buffer.

Recalibrate with
fresh buffer.

1) for pH = 6.86, added 8 mV to the values.

Error

Care and Maintenance

Cleaning

§ Unplug the AC adapter from the wall outlet.

§ Clean the pH meter using a piece of cloth which has

been wet with a mild detergent

§ Wipe down the pH meter with a soft cloth.
$ Cleaning the electrode: refer to the Instructions for

Use of the particular electrode.

! Make sure that no liquid enters the instrument.
!Do not use any aggressive cleaning agents

(solvents or similar agents)

Safety Inspection

If there is any indication that safe operation of the
equipment is no longer guaranteed:

§ Disconnect the power cord from the outlet
> Ensure that the equipment cannot be used during

this time. Notify your nearest Sartorius Service
Center.
Maintenance and repair work may only be
performed by specialized service technicians.

Recycling Instructions

To ensure adequate protection for safe shipment,
your instrument has been packaged to the extent
necessary using environmentally friendly materials.
After successful installation of the instrument, you
should return this packaging for recycling because
it is a valuable source of secondary raw material.
For information on recycling options, including
recycling of old weighing equipment, contact your
municipal waste disposal center or local recycling
depot.

33

34

Overview

Meter Specifications

Docu-pH

Meter

Docu-pH

+

Meter

pH measurement

Measuring range -2.000 … 20.000
Readability 0.001 | 0.01 | 0.1, adjustable
Accuracy ± 0.005

mV measurement

Measuring range in mV –2000.0 … +2000.0
Readability in mV 0.1 | 1 adjustable
Accuracy in mV ± 0.2 < | 1000 | ± 1 > | 1000 |

Temperature measurement

Measuring range in °C –5 … 105
Readability in °C 0.1
Accuracy in °C ± 0.2
Temperature compensation Automatic or manual from -5°C … 105°C
Buffer recognition Automatic: technical buffers, DIN/NIST buffers
Calibration points, max. number 3
Date|Time battery-supplied - +
Sample IDs - +
Calibration reminder - +
Complete GLP-compliant record - +
Memory for measurement data - +
Communication with DocuClip

®

++

Input for pH combination electrodes BNC BNC
Input for temperature probes
NTC 10 kO, NTC 30 kO, Pt1000 2.5 mm phone plug 2.5 mm phone plug
Interface RS232C – +
Dimensions in mm 89 + 229 + 145
Weight in kg 1

35

Accessories

Order No.

pH/ATC combination electrodes with DocuClip

®

; Clip ready installed and precalibrated:
Gel electrolyte, fiber junction with integrated ATC probe PY-P12doc
Gel electrolyte, fiber junction PY-P20doc
KCI liquid-filled, fiber junction with integrated ATC probe PY-P10doc
KCI liquid-filled, platinum junction with integrated ATC probe PY-P11doc
KCI liquid-filled, platinum junction PY-P21doc
KCI liquid-filled, platinum junction (microelectrode) PY-P22doc
Gel electrolyte-filled, annular gap junction (surface electrode) PY-P23doc
KCI liquid-filled, adjustable flow rate, sleeve junction PY-P24doc

All Sartorius pH electrodes standard equipped without DocuClip

®

PY-P...

DocuClip

®

for use with any electrode DocuClip®

Redox/ORP combination electrode with DocuClip

®

, Clip ready installed:

KCI liquid-filled, platinum disk PY-R01doc

ATC probe:

10 kO NTC PY-T01

pH buffer solutions:

Buffer pH = 4.00 (0.01 at 25°C), twin-neck bottle, 500 ml PY-Y21
Buffer pH = 7.00 (0.01 at 25°C), twin-neck bottle, 500 ml PY-Y22
Buffer pH = 10.00 (0.01 at 25°C), twin-neck bottle, 500 ml PY-Y23

Cleaning solution, pepsin | hydrochloric acid, 500 ml PY-Y06
Electrolyte solution, KCl (3 mol/L), silver ion-free, 500 ml PY-Y07

Sartorius lab printer YDP05-pH

“IQ | OQ” Qualification for pH meter 8407pH

36

C

Sartorius AG
Weender Landstrasse 94–108
37075 Goettingen, Germany

Phone [phone]
Fax [phone]
www.sartorius.com

Copyright by Sartorius AG,
Goettingen, Germany.
All rights reserved. No part
of this publication may
be reprinted or translated in
any form or by any means
without the prior written
permission of Sartorius AG.
The status of the information,
specifications and illustrations
in this manual is indicated
by the date given below.
Sartorius AG reserves the
right to make changes to the
technology, features,
specifications and design of the
equipment without notice.

Status:
February 2007, Sartorius AG,
Goettingen, Germany

Printed in Germany on paper that has
been bleached without any use of chlorine
W1A000 · KT
Publication No.: WDO6003-e07023