Xylem WTW OxiTop-i User manual

OPERATING MANUAL
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OxiTop®-i
OxiTop®-IDS
MEASURING HEADS FOR BOD DETERMINATION (RESPIROMETRIC TEST PROCEDURE)
OPERATING MANUAL

OxiTop®(-i/-IDS)
2ba77059e01 03/2019
Copyright © 2019 Xylem Analytics Germany GmbH
Printed in Germany.

Index
OxiTop®(-i/-IDS) Index
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1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1 Measuring system OxiTop®. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Measuring heads OxiTop®(-i/-IDS) (variants) . . . . . . . . . . . . . . . . . 5
1.3 Measuring principle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 Operation of the measuring heads . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.5 Supporting functions for BOD measurements. . . . . . . . . . . . . . . . . 7
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1 Safety information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.1 Safety information in the operating manual . . . . . . . . . . 8
2.1.2 Safety signs on the meter . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.1.3 Further documents providing safety information . . . . . . . . 8
2.2 Safe operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2.2 Requirements for safe operation . . . . . . . . . . . . . . . . . . . . 9
2.2.3 Unauthorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1 Scope of delivery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2 Power supply (OxiTop®measuring heads). . . . . . . . . . . . . . . . . . 10
3.3 Initial commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1 General operating principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1.1 Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1.2 Status information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2 Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2.1 Operating modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2.2 Menus and dialogs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2.3 Elements in menus and dialogs . . . . . . . . . . . . . . . . . . . . 14
4.2.4 Example on navigation: Setting the language . . . . . . . . . 14
4.2.5 Example on navigation: Setting the date . . . . . . . . . . . . . 15
4.3 BOD determination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.4 Carrying out the BOD determination . . . . . . . . . . . . . . . . . . . . . . . 16
4.4.1 Preparing the measurement. . . . . . . . . . . . . . . . . . . . . . . 16
4.4.2 Starting the measurement . . . . . . . . . . . . . . . . . . . . . . . . 18
4.4.3 Displaying measurement data . . . . . . . . . . . . . . . . . . . . . 19
4.5 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.5.1 OxiTop®-PM (Cal-Test) . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.5.2 OxiTop®-PT (pneumatic test). . . . . . . . . . . . . . . . . . . . . . 21
4.6 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.6.1 Measurement settings . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Index OxiTop®(-i/-IDS)
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4.6.2 System settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5 Maintenance, cleaning, disposal . . . . . . . . . . . . . . . . . . . . . . . 24
5.1 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1.1 Exchanging the battery. . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.2 Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.2.1 Measuring head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.2.2 Sample bottles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.3 Packing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.4 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6 What to do if.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
7 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

OxiTop®(-i/-IDS) Overview
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1 Overview
The measuring heads OxiTop®(-i/-IDS) are part of the OxiTop®measuring sys-
tem for BOD determination.
1.1 Measuring system OxiTop®
The OxiTop®measuring system consists of the following components:
Stirring platform IS 6, IS 12, IS 6 VAR
Sample bottles
Measuring head OxiTop®(-i/-IDS)
Only for the measuring heads OxiTop®-IDS:
IDS meter with MultiLine OxiTop®IDS software for wireless operation of the
OxiTop®-IDS measuring heads
1.2 Measuring heads OxiTop®(-i/-IDS) (variants)
figure 1-1 OxiTop®(-i/-IDS) variants
1OxiTop
®-i B (blue)
2OxiTop
®-i G (gray)
3OxiTop
®-IDS (orange)
4OxiTop
®-IDS /B (orange/gray)
1
3
2
4

Overview OxiTop®(-i/-IDS)
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Measuring heads
(variants)
1.3 Measuring principle
BOD determination with the OxiTop®measuring system is based on pressure
measurement (difference measurement). The recording of the measured val-
ues is done by means of pressure measurement via piezo-resistive electronic
pressure sensors.
1.4 Operation of the measuring heads
Operating elements
of the measuring
heads
All OxiTop®(-i/-IDS) measuring heads can be operated with the operating ele-
ments at the measuring heads (details: see present operating manual).
Wireless operation Additionally, the OxiTop®-IDS measuring heads can be connected to a meter
wirelessly via the WLM system. The meter must be equipped with the BOD
software MultiLine OxiTop®IDS.
As soon as the measuring heads are connected to the meter wirelessly via the
WLM system, you can operate several measuring heads conveniently and
simultaneously.
With the meter, several additional options for evaluation, processing and output
of the measurement data are available (e.g. output to a USB memory device or
a PC).
Characteristics OxiTop®variants
-i -IDS -IDS /B
Color Gray or
blue
Orange Orange/
gray
Operating elements
(display and keys)
xx
Wireless operation x
Transmitting measurement data x
Suitability for biogas x
Max. measured values 7360
Max. measuring duration (days) 7180
Details on the wireless operation of the OxiTop®-IDS measuring
heads via a meter is given in the "MultiLine OxiTop®IDS operating
manual for Multi 3630/3620 IDS".
The general functions of the meter, e.g. transmitting measurement
data to a PC, are described in the operating manual of your
Multi 3630 IDS or Multi 3620 IDS meter.

OxiTop®(-i/-IDS) Overview
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1.5 Supporting functions for BOD measurements
To reduce the measuring work and costs, the OxiTop®measuring system is
especially adapted to the procedures of respirometric BOD measurement by
means of the following functions:
Function Explanation
AutoTemp Function to control the temperature adjustment.
Measurement is started automatically (at least 1 hour,
at most 3 hours after the OxiTop®measuring head is
started).
Pre-tempering the samples to exactly 20°C is not
required! The samples can be inserted with a tempera-
ture in the range of 15°C ... 21°C. The AutoTemp func-
tion takes over the temperature control.
Measured value
memory
OxiTop®-i: Automatic measurement with daily mea-
sured value recording for 7 days:
OxiTop®-IDS: Automatic measurement with daily mea-
sured value recording for 180 days: The setting of
more than 7 measured values is only possible via the
wirelessly connected meter.
Momentary
value
Display of the current measured value in the selected
unit at any timer during a measurement.

Safety OxiTop®(-i/-IDS)
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2 Safety
2.1 Safety information
2.1.1 Safety information in the operating manual
This operating manual provides important information on the safe operation of
the instrument. Read this operating manual thoroughly and make yourself
familiar with the instrument before putting it into operation or working with it.
The operating manual must be kept in the vicinity of the instrument so you can
always find the information you need.
Important safety instructions are highlighted in this operating manual. They are
indicated by the warning symbol (triangle) in the left column. The signal word
(e.g. "CAUTION") indicates the danger level:
NOTE
indicates a possibly dangerous situation where goods might be damaged
if the actions mentioned are not taken.
2.1.2 Safety signs on the meter
Note all labels, information signs and safety symbols on the meter and in the
battery compartment. A warning symbol (triangle) without text refers to safety
information in this operating manual.
2.1.3 Further documents providing safety information
The following documents provide additional information, which you should
observe for your safety when working with the measuring system:
• Operating manuals of further accessories
• Safety datasheets of calibration- or maintenance accessories
WARNING
indicates a possibly dangerous situation that can lead to seri-
ous (irreversible) injury or death if the safety instruction is not
followed.
CAUTION
indicates a possibly dangerous situation that can lead to
slight (reversible) injury if the safety instruction is not fol-
lowed.

OxiTop®(-i/-IDS) Safety
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2.2 Safe operation
2.2.1 Authorized use
The authorized use of the OxiTop®-IDS measuring system is the respirometric
determination of the Biochemical Oxygen Demand (BOD) according to the self-
monitoring procedure, as well as additional respirometric test procedures.
Only the operation and running of the instrument according to the instructions
and technical specifications given in this operating manual is authorized (see
section 7 TECHNICAL DATA, page 28).
Any other use is considered unauthorized.
2.2.2 Requirements for safe operation
Note the following points for safe operation:
• The instrument may only be operated according to the authorized use spec-
ified above.
• The instrument may only be supplied with power by the energy sources
mentioned in this operating manual.
• The instrument may only be operated under the environmental conditions
mentioned in this operating manual.
• The instrument may only be opened if this is explicitly described in this oper-
ating manual (example: Inserting the batteries).
2.2.3 Unauthorized use
The instrument must not be put into operation if:
• it is visibly damaged (e.g. after being transported)
• it was stored under adverse conditions for a lengthy period of time (storing
conditions, see section 7 TECHNICAL DATA, page 28).

Commissioning OxiTop®(-i/-IDS)
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3 Commissioning
3.1 Scope of delivery
OxiTop®measuring heads are included in several scopes of delivery that con-
tain also other accessories or a varying number of measuring heads.
Here, only those scopes of delivery are listed that include only measuring
heads (without any other accessories):
Measuring head / measuring heads (number of heads in set compositions)
– OxiTop®-IDS ( /2/6) (number: 1, 2 or 6)
– OxiTop®-IDS/B
– OxiTop®-i G
– OxiTop®-i B
– OxiTop®-i 6 (number: 3 x OxiTop®-i G and 3 x OxiTop®-i B)
– OxiTop®-i 12 (number: 6 x OxiTop®-i G and 6 x OxiTop®-i B)
Operating manual
3.2 Power supply (OxiTop®measuring heads)
All OxiTop®measuring heads are supplied with power by batteries (see section
7T
ECHNICAL DATA).
3.3 Initial commissioning
No extra steps are required for the initial commissioning of an OxiTop®mea-
suring head.
Each measuring head can be assigned an individual ID (see section
4.6.2 SYSTEM SETTINGS), so the measurement values can be correctly assigned
to the measuring heads and sample bottles.

OxiTop®(-i/-IDS) Operation
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4Operation
The OxiTop®-i measuring heads are exclusively operated with the keys on the
measuring heads.
The OxiTop®-IDS measuring heads are optionally operated via a wirelessly
connected control meter (Multi 3630/3620 IDS) or via the keys on the measur-
ing heads.
4.1 General operating principles
Keys In this operating manual, keys are indicated by brackets <..> .
The key symbol (e.g. <ENTER>) generally indicates a short keystroke (under
2 sec) in this operating manual. A long keystroke (approx. 2 sec) is indicated
by the underscore behind the key symbol (e.g. <ENTER_>).
figure 4-1 Control panel example: OxiTop®-IDS
1 LED to indicate operating conditions
2 IDS measuring head (suitable for wireless communication)
3 Display
4Key
<M>
5Key
<ENTER>
6 Navigation key <
>
1
456
2
3
To switch a measuring head on, press any key.

Operation OxiTop®(-i/-IDS)
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4.1.1 Display
4.1.2 Status information
Status information in
the display
<M> In the start display (ID...):
Display the measurement settings
(Info display BOD parameters)
In the info display BOD parameters:
Start the measurement
In menus/submenus/settings:
Take over the selection / entry,
Exit the menu/submenu and
go one level higher
<M_> Switch off the measuring head
(if a measurement is running, there is a security prompt
for confirmation)
<ENTER> In the start display (ID...) / info display (BOD parame-
ters):
Open the menu for measurement settings
In menus: Confirm selection / entry
<ENTER_> In the start display (ID...) / info display (BOD parameters):
Open the menu for system settings
< >In menus: Navigation in the menu
In the selection: change numerical values
<_ >Only for OxiTop®-IDS
Establish wireless connection to the meter
1 ID of the measuring head
2 Info on displayed measured value
3 Measured value
4 Date and time
2
4
3
BSB4.1 [mg/l]:
64.9
ID: 11
25.01.2019 08:22
1
Batteries almost empty.
Before starting a BOD measurement, exchange the batter-
ies (see section 5.1.1 EXCHANGING THE BATTERY).
For suitable measures, see section 6 WHAT TO DO IF...

OxiTop®(-i/-IDS) Operation
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Status LED The status LED indicates the current state of a BOD measurement.
The LED flashes slowly (approx. every 5 secionds).
4.2 Navigation
The principles of navigation in menus and dialogs are explained in the following
sections.
4.2.1 Operating modes
The instrument has the following operating modes:
Only those displays and functions are available in the active operating mode
that are currently being required.
4.2.2 Menus and dialogs
The menus for settings and dialogs in procedures contain further subelements.
Select a submenu or change a numerical value with the <
>key.
Using <ENTER>, activate (
 ) or deactivate a function, or
confirm a numerical value and switch to the next digit.
Press <M>
– to take over a selection / entry,
– to quit a menu/submenu/setting or
– to go to the superordinate level.
Color Explanation
BLUE The BOD measurement was started.
Green The BOD measurement is finished.
The status LED flashes green for approx. 24 hours.
Red The BOD measurement was started.
The measuring head is in a critical condition:
The battery is nearly discharged
or
The pressure in the sample bottles is too high.
For suitable measures, see section 6 WHAT TO DO IF...
Operating
mode
Explanation
Measuring The measurement data of the connected sensor are shown
in the measured value display
Setting The display indicates a menu, submenu, settings or func-
tions

Operation OxiTop®(-i/-IDS)
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4.2.3 Elements in menus and dialogs
Submenus
Menu items that open a submenu are indicated by an arrow pointing to the
right side ().
Submenus are opened by confirming with <ENTER>. Example:
Numerals settings (e.g. date/time)
The first digit is indicated by an undescore.
– using <
>, change the digit with the undescore
– using <ENTER>, confirm the digit and go to the next digit.
– using <M>, confirm the entire number (e.g. date or time and exti the set-
ting.
Functions (activate/deactivate)
Active functions are indicated by a checkmark  next to the function name.
The are activated/deactivated by being confirmed with <ENTER>.
Example: function Illumination
 , language Deutsch  .
4.2.4 Example on navigation: Setting the language
1. Switch on the measuring head with <M>.
The current ID of the measuring head is displayed.
2. Open the system menu with <ENTER_>.
3. Using <
>, highlight the General menu.
4. Using <ENTER>, open the General menu.
General 
Clock function 
Service 
25.02.2019
General 
Clock function 
Service 

OxiTop®(-i/-IDS) Operation
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4.2.5 Example on navigation: Setting the date
5. Using <
>, highlight the Language setting.
6. Using <ENTER>, open the Language menu.
7. Select the required language with <
>.
8. Confirm the setting with <ENTER>.
The menu is closed.
The measuring head is restarted.
The selected language is active.
1. Switch on the measuring head with <M>.
The instrument ID is displayed.
2. Open the system menu with <ENTER_>.
3. Using <
>, highlight the Clock function menu.
4. Using <ENTER>, open the Clock function menu.
5. Using <
>, highlight the Date... setting.
6. Using <ENTER>, open the Date... menu.
7. Using <
>, select the number for the highlighted digit.
8. Using <ENTER>, confirm the number for the selected digit and go to the
next digit.
9. Repeat the two last steps for all digits.
Deutsch 
English
Français
Español
General 
Clock function 
Service 
25.01.2019

Operation OxiTop®(-i/-IDS)
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4.3 BOD determination
Municipal wastewater does not normally contain any toxic or inhibiting sub-
stances. There are enough nutrient salts and suitable microorganisms present.
Under these conditions, BOD determination in the undiluted sample using the
OxiTop®(-i/-IDS) measuring system is possible.
Instruments and
accessories
required
OxiTop®(-i/-IDS) measuring head
Stirring platform (inductive stirring system)
Thermostat cabinet or box (temperature 20 °C ± 1 °C)
Brown sample bottles (bottle volume 510 ml)
Magnetic stirring rods
Magnetic stirring rod remover
Suitable overflow volumetric flask
Rubber sleeves
Nitrification inhibitor (NTH 600)
Sodium hydroxide tablets (NHP 600)
Further documents
for BOD
determination
WTW application reports (see www.wtw.com)
DIN EN 1899-2
Water quality - Determination of biochemical oxygen demand after n days
(BODn) - Part 2: Method for undiluted samples (ISO 5815:1989, modified);
German version EN 1899-2:1998
4.4 Carrying out the BOD determination
4.4.1 Preparing the measurement
Determining the
sample volume
10. Exit the setting with <M>.
1. Estimate the expected BOD value for the waste water sample.
The expected BOD value is approximately 50% of the COD value.
2. Look for the relevant measuring range in the following table and take
the values for sample volume and multiplier.

OxiTop®(-i/-IDS) Operation
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Preparing the
stirring platform
Preparing the
sample bottles
Preparing the
measuring head
Preparing the
samples
Sample volume [ml] Measuring range
[mg/l]
Multiplier *
432 0 - 40 1
365 0 - 80 2
250 0 - 200 5
164 0 - 400 10
97 0 - 800 20
43,5 0 - 2000 50
22,7 0 - 4000 100
* for conversion of digits (only for the setting: Unit...[digit])
Too big a measuring range will lead to inaccurate results.
A measuring range selected too small will cause the results to be
not evaluable.
1. Install a stirring platform for the sample bottles in a temperature-con-
trolled environment (e.g. in a thermostat cabinet or thermobox, see
operating manual of the thermostat cabinet or thermobox).
2. Rinse the sample bottles with the water sample and let the water drip
off well.
3. Check and specify the measurement settings at the measuring heads.
4. Follow the specification (and application reports) and exactly measure
the oxygen-saturated (well homogenized) sample volume required.
To measure the sample volume, overflow measuring flasks or mea-
suring cylinders are normally used.
5. Place the magnetic stirring rod in the sample bottle.
6. Fill the measured sample volume into the sample bottle.
7. Add nitrification inhibitor NTH 600 (see table).

Operation OxiTop®(-i/-IDS)
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4.4.2 Starting the measurement
Measuring
range BOD
[mg/l]
Sample volume [ml]
(overflow measuring
flask)
Quantity of NTH 600
[drops per sample bot-
tle]
0 - 40 432 9
0 - 80 365 7
0 - 200 250 5
0 - 400 164 3
0 - 800 97 2
0 - 2000 43,5 1
0 - 4000 22,7 1
To guarantee an optimum and safe stirring function:
Use only original accessories (RST 600 stirring rod).
8. Insert a rubber sleeve into the bottle neck.
9. Place 2 sodium hydroxide tablets in the rubber sleeve using tweezers.
The sodium hydroxide tablets must not get into the sample!
10. Screw the OxiTop®measuring head directly on the sample bottle
(close tightly).
11. Place all sample bottles in the center of the stirring places on the stir-
ring platform.
12. Observe the stirring operation, correct the bottle positions if necessary.
(see operating manual of the stirring platform)
13. For OxiTop®-IDS :
Connect the measuring heads with the meter (see operating manual
"Multi 3630/3620 IDS operation with OxiTop®-IDS".
1. Display the info display (BOD parameters) with <M>.
Check the settings. If necessary, change the measurement set-
tings with <ENTER>.

OxiTop®(-i/-IDS) Operation
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4.4.3 Displaying measurement data
You can view the measurement data during a measurement (LED flashes blue)
and after a measurement (LED flashes green).
2. Start the measurement with <M>.
If the signal LED is active, it will flash blue.
AutoTemp is displayed.
3. Keep the sample bottle (with the OxiTop®(-i/-IDS) measuring head
screwed on) in a place that is controlled to 20°C (e.g. thermostat cabi-
net/box) for the specified number of days.
When the measuring temperature has been reached (function Auto-
Temp: after at least 1 hour, at most approx. 3 hours), the OxiTop®(-i/-
IDS) measuring head automatically starts measuring the oxygen con-
sumption.
4. Stir the sample continuously during the specified measuring duration
(stirring platform).
During the specified measuring duration, the OxiTop®(-i/-IDS) measur-
ing head automatically saves a measured value once every 24 hours.
5. Read out the saved measured values after the specified measuring
duration has expired.
If the signal LED is active, it will flash green.
1. When the display is switched off:
Switch on the display with any key.
The current value (during measurement) or the value last determined
(after the end of the measurement) is displayed.
2. Using <
>, scroll through the values stored last.
The measured value can be assigned to the day via the index
(BOD0,1,2 ...7).
3. You can display the measured values as a graphic with <_
>.

Operation OxiTop®(-i/-IDS)
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4.5 Calibration
Why calibrate? The condition of the heads can be evaluated by checking the tightness and
measuring accuracy (see BOD application report).
When to calibrate? Routinely within the framework of the company quality assurance
Calibration
procedure
Creation of a defined negative pressure and balancing with the display (see
BOD application report).
In contrast to physical or chemical measuring methods, BOD systems do not
provide standardized values, as the use of microorganisms has a great spec-
trum depending on their composition and food supply. With the aid of testing
tools and suitable tests, errors due to defective pressure sensors or untight
measuring head threads can be identified.
You can check the OxiTop®(-i/-IDS) measuring heads with the following proce-
dures.
OxiTop®-PM (Cal-Test)
OxiTop®-PT (pneumatic test)
figure 4-2 Graphic display of a BOD measurement
1 Y-axis: Measured value
2 X-axis: Days
3Cursor
4. Using <
>, indicate the measured value of the individual days with
the cursor.
5. Using <_
>, quit the graphic display.
The stored data are displayed again.
6. Terminate the display of the stored measured values with <M>.
BSB[mg/l]
7 [d]
+
10.9
0
3
1
2