Burkert MS09 User manual

Type MS09
Nitrate Sensor
Operating Instructions

We reserve the right to make technical changes without notice.
© Bürkert SAS, 2021
Operating Instructions 2110/00_EU-ML 00572429 / Original EN

Type MS09
Table of contents
3
TABLE OF CONTENTS
1 About this document..................................................................................................................................8
1.1 Manufacturer .................................................................................................................................... 8
1.2 Used symbols................................................................................................................................... 8
1.3 Terms and abbreviations .................................................................................................................. 9
2 Safety instructions....................................................................................................................................10
2.1 Warranty ......................................................................................................................................... 10
2.2 Intended use................................................................................................................................... 10
2.3 General safety information ............................................................................................................. 10
3 Product description..................................................................................................................................13
3.1 Design............................................................................................................................................. 13
3.1.1 ME63 Sensor Interface ......................................................................................................13
3.1.2 MS09 Nitrate Sensor..........................................................................................................14
3.1.3 Flow cell .............................................................................................................................14
3.2 Display elements ............................................................................................................................ 15
3.2.1 Product status indicator ....................................................................................................16
3.3 Markings ......................................................................................................................................... 17
3.3.1 Type label...........................................................................................................................17
3.3.2 Conformity marking ...........................................................................................................18
3.4 Memory Card.................................................................................................................................. 18
3.5 Operating principle ......................................................................................................................... 18
4 Technical data ..........................................................................................................................................22
4.1 Operating conditions ...................................................................................................................... 22
4.2 Product materials ........................................................................................................................... 22
4.3 Conformity ...................................................................................................................................... 22
4.4 Dimensions, weight ........................................................................................................................ 23
4.5 Performance data ........................................................................................................................... 23
4.6 Fluid data........................................................................................................................................ 24
4.7 Electrical data ................................................................................................................................. 24
5 Installation ................................................................................................................................................25
5.1 Safety instructions .......................................................................................................................... 25
5.2 Installing procedure ........................................................................................................................ 25
6 Electrical connection................................................................................................................................28
6.1 Connection plan MS09 ................................................................................................................... 28
6.2 Connection plan ME63 ................................................................................................................... 29
6.3 Assignment of the connections ...................................................................................................... 29
6.4 Supply voltage................................................................................................................................ 31
6.5 M12 8 pins Nitrate Sensor connection ........................................................................................... 31
7 Commissioning.........................................................................................................................................33
7.1 Safety instructions .......................................................................................................................... 33

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7.2 Manufacturer calibration................................................................................................................. 33
7.3 Path length check........................................................................................................................... 33
7.3.1 Turbidity and organics compensation ...............................................................................33
7.3.2 Nitrite .................................................................................................................................33
7.3.3 Salinity ...............................................................................................................................34
7.3.4 Path lengths and limit values .............................................................................................34
7.3.5 Unknown substances ........................................................................................................35
7.4 Install the micro SD card ................................................................................................................ 35
7.5 Transfer data to or from another product....................................................................................... 36
8 Setting and operation...............................................................................................................................38
8.1 Safety instructions .......................................................................................................................... 38
8.2 Setting tools and setting software.................................................................................................. 38
8.3 Description of the user interface .................................................................................................... 38
8.4 Available login user levels............................................................................................................... 39
8.5 Product functions and menus ........................................................................................................ 40
9 Sensor - Parameter ..................................................................................................................................41
9.1 Select the type of sensor connected to the ME63 interface .......................................................... 41
9.2 Define the organic compensation level .......................................................................................... 42
9.3 Set the interval for the automatic measurements........................................................................... 42
9.4 Adjust the measure values (customer calibration).......................................................................... 42
9.5 Monitor the values of the water sample ......................................................................................... 43
9.6 Freeze the values transmitted on the fieldbus................................................................................ 44
9.6.1 Manual freeze ....................................................................................................................45
9.6.2 Automatic freeze ................................................................................................................45
9.6.3 Change the binary event for the automatic freeze.............................................................46
9.6.4 Stop the manual freeze or the automatic freeze................................................................47
10 Sensor - Diagnostics ................................................................................................................................48
10.1 Check sensor information............................................................................................................... 49
10.2 Check calibration values ................................................................................................................ 49
10.3 Check measured values ................................................................................................................. 49
10.4 Check values for advanced diagnostics......................................................................................... 50
11 Sensor - Maintenance ..............................................................................................................................51
11.1 Stop the simulation mode .............................................................................................................. 51
11.2 Start the simulation mode .............................................................................................................. 51
11.3 Manually start a measurement ....................................................................................................... 52
11.4 Calibrate the zero value (base intensity)......................................................................................... 52
11.5 Plan the calibrations ....................................................................................................................... 53
11.6 Activate or deactivate the service mode ........................................................................................ 53
12 General Settings - Parameter ..................................................................................................................55
12.1 Set the colours and behaviour of the device status LED ............................................................... 56
12.2 Enter a name for the product ......................................................................................................... 56

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12.3 Enter the location of the product.................................................................................................... 57
12.4 Enter a description for the product ................................................................................................ 57
12.5 Enter a unique name for the product.............................................................................................. 57
12.6 Change the transmission speed of the product ............................................................................. 57
12.7 Address of a product connected to büS ........................................................................................ 58
12.8 Change the address of the product connected to a CANopen fieldbus ........................................ 58
12.9 Read the actually used CANopen address (Node ID) .................................................................... 58
12.10 Set the digital communication for büS or for a CANopen fieldbus ................................................ 58
12.11 Set the CANopen status................................................................................................................. 59
12.12 Show errors from büS partners ...................................................................................................... 59
12.13 Stop sending the measured process data (PDOs) to büS or to the CANopen fieldbus................. 59
12.14 Change the time to check the presence of a participant on the fieldbus....................................... 60
12.15 Monitor the supply voltage ............................................................................................................. 60
12.16 Monitor the device temperature ..................................................................................................... 61
12.17 Disable or enable the diagnostics .................................................................................................. 61
12.18 Set the transmission time between 2values of a PDO .................................................................. 63
12.19 Restore all PDOs to their default values......................................................................................... 64
13 General Settings - Diagnostics ................................................................................................................65
13.1 Read the current device temperature............................................................................................. 66
13.2 Read the current supply voltage .................................................................................................... 66
13.3 Read the number of voltage drops since the last restart ............................................................... 66
13.4 Read the maximum and minimum values of the device temperature and the supply voltage....... 66
13.5 Read the number of product starts ................................................................................................ 66
13.6 Check the presence of the memory card ....................................................................................... 67
13.7 Read the current time ..................................................................................................................... 67
13.8 Read the number of current receive errors..................................................................................... 67
13.9 Read the maximum number of receive errors since the last power-up of the device.................... 67
13.10 Read the number of current transmit errors ................................................................................... 67
13.11 Read the maximum number of transmit errors since the last power-up of the device .................. 68
13.12 Reset the 2 maximum error counters ............................................................................................. 68
13.13 Read whether the measured process data is sent on büS or on the CANopen fieldbus............... 68
13.14 Read the generated events ............................................................................................................ 68
14 General Settings - Maintenance ..............................................................................................................70
14.1 Read device information................................................................................................................. 70
14.2 Restart the product......................................................................................................................... 71
14.3 Reset the product to its factory settings ........................................................................................ 71
14.4 Restart the sensor .......................................................................................................................... 72
15 Maintenance .............................................................................................................................................73
15.1 Safety instructions .......................................................................................................................... 73

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15.2 Maintenance data ........................................................................................................................... 73
15.3 Replace the memory card .............................................................................................................. 74
15.4 Maintenance and inspection .......................................................................................................... 74
15.5 Cleaning and upkeep...................................................................................................................... 74
15.5.1 Cleaning the enclosure ......................................................................................................74
15.5.2 Cleaning the measuring window........................................................................................75
15.5.3 Preparing the sensor for the function test and zero value determination..........................76
15.6 Checking the zero value ................................................................................................................. 77
16 Troubleshooting .......................................................................................................................................78
16.1 Troubleshooting with messages..................................................................................................... 78
16.2 Messages [ERROR]: failure, error or malfunction........................................................................... 78
16.2.1 Message Select sensor and restart the device................................................................78
16.2.2 Message Communication with the sensor is interrupted................................................78
16.2.3 Message Sensor error (internal error). Contact the service for your device ..................79
16.2.4 Message büS event: producer not found.........................................................................79
16.2.5 Message büS is not operational .......................................................................................79
16.3 Messages [OUT OF SPECIFICATION]: out of specification ........................................................... 79
16.3.1 Message Warning: Quality of measurement limited (SQI). Check sensor and process
...........................................................................................................................................79
16.3.2 Message Warning: Quality of measurement limited (NO3). Check sensor and process
...........................................................................................................................................80
16.3.3 Message Error: Quality of measurement significantly reduced (SQI). Check sensor and
process..............................................................................................................................80
16.3.4 Message Error: Quality of measurement significantly reduced (NO3). Check sensor and
process..............................................................................................................................80
16.4 Messages [FUNCTION CHECK]: function check ........................................................................... 80
16.4.1 Message Simulation mode active.....................................................................................81
16.4.2 Message Hold mode active ..............................................................................................81
16.5 Messages [MAINTENANCE]: maintenance required ...................................................................... 81
16.5.1 Message Device is in service mode, no communication with sensor ............................81
16.5.2 Message Path length could not be set.............................................................................81
16.5.3 Message Calibration setting could not be set .................................................................82
16.5.4 Message Deviation from default settings detected, resets to default settings..............82
16.5.5 Message Last calibration is older than 1 days. Recalibrate your device.......................82
16.5.6 Message Sensor error (invalid baseline). Contact the service for your device ..............82
16.5.7 Message Sensor error (optical path length too short). Contact the service for your
device ................................................................................................................................83
16.5.8 Message Sensor error (optical path length too long). Contact the service for your
device ................................................................................................................................83
16.6 Messages [INFO]: information ........................................................................................................ 83
16.6.1 Message Sensor error (data transfer failed). Contact the service for your device ........83
16.6.2 Message Sensor error (UPS error). Contact the service for your device .......................83
16.6.3 Message Sensor error (power fail detected). Contact the service for your device........84
16.6.4 Message Transferable memory is not accessible ...........................................................84
17 Spare parts and accessories ...................................................................................................................85
17.1 MS09 Nitrate Sensor accessories .................................................................................................. 85
18 Uninstallation ............................................................................................................................................86

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18.1 Safety instructions .......................................................................................................................... 86
18.2 Uninstalling procedure.................................................................................................................... 86
19 Logistic .....................................................................................................................................................87
19.1 Transport ........................................................................................................................................ 87
19.2 Storage ........................................................................................................................................... 87
19.3 Return ............................................................................................................................................. 87
19.4 Disposal .......................................................................................................................................... 87

Type MS09
About this document
8
1 ABOUT THIS DOCUMENT
The document is an important part of the product and guides the user to safe installation and operation.
The information and instructions in this document are binding for the use of the product.
▪Before using the product for the first time, read and observe the whole safety chapter.
▪Before starting any work on the product, read and observe the respective sections of the document.
▪Keep the document available for reference and give it to the next user.
▪Contact the Bürkert sales office for any questions.
Further information concerning the product at country.burkert.com.
1.1 Manufacturer
Bürkert SAS
Rue du Giessen
F-67220 TRIEMBACH-AU VAL
The contact addresses are available at country.burkert.com in the Contact menu.
1.2 Used symbols
DANGER!
Warns of a danger that leads to death or serious injuries.
WARNING!
Warns of a danger that can lead to death or serious injuries.
CAUTION!
Warns of a danger that can lead to minor injuries.
ATTENTION!
Warns of property damage that can damage the product or the installation.
Indicates important additional information, tips and recommendations.
Refers to information in this document or in other documents.
Indicates an instruction to avoid a danger.
Indicates a step to be carried out.
Indicates a result.
Menu Indicates a software user-interface text.

Type MS09
About this document
9
1.3 Terms and abbreviations
The terms and abbreviations are used in this document to refer to following definitions.
Product MS09
▪Photometer, digital
büS Bürkert system bus, a communication bus developed by Bürkert and based on the
CANopen protocol
NAMUR Standards committee for measurement and control technology (NAMUR) is an inter-
national association of users of automation systems for the process industry.
NAMUR recom-
mendation NE107
Self-monitoring and diagnosis of field devices.

Type MS09
Safety instructions
10
2 SAFETY INSTRUCTIONS
2.1 Warranty
The warranty is conditional on compliant use of the product in observance of the operating conditions.
2.2 Intended use
Improper use of the product may be a hazard to people, nearby equipment and the environment.
MS09 is used exclusively for the implementation of NO3 or photometric measurements as described in
this manual. The product has been developed for use in industrial an municipal water treatment plants.
The ME63 Sensor Interface is used to connect the Sensor Types MS08 and MS09 into Bürkert büS net-
works.
The flow cell is used to install the Nitrate Sensor as a bypass.
▶The sensor may only be used to measure the NO3 and transmission of aqueous fluids with water qualit-
ies equal or better than drinking water. The use of other media can damage the sensor. For the use of
the product in other media then those specified this manual, please contact the Bürkert Customer Ser-
vice
▶The photometer is an immersion sensor, which is used underwater or with flow cells. Please note the
technical data of the accessory parts. Other uses do not comply with the intended use.
▶Observe the data (additional data, operating conditions, service conditions) in the contract documents,
in the Operating Instructions, on the type label and on the calibration label.
▶Only use the product with external instruments that the product manufacturer recommends.
▶Only use the product up to an altitude of 2000m.
▶Only use the product with components that the product manufacturer recommends.
▶Operate the product carefully and ensure regular and professional maintenance.
▶Operate the product only in perfect working order.
▶Ensure appropriate storage, transport, installation and use.
▶Only use the product for its intended purpose.
Qualification of the personnel
The target group for the operation of the product is technically skilled staff in plants, water plants and insti-
tutes. Operating this product often requires the handling of hazardous substances. Operating personnel
must be familiar with dealing with dangerous substances based on their professional training and experi-
ence. Operating personnel must be able to correctly understand and implement the safety labels and in-
formation on the packaging and in the package inserts of the test kits.
2.3 General safety information
These safety instructions do not take into account any unforeseen circumstances and events which occur
during installation, operation and maintenance.
The operator is responsible for observing the location-specific safety regulations, also with reference to the
personnel.

Type MS09
Safety instructions
11
To prevent injuries and product damage, observe the following:
▶Install the product according to the regulations applicable in the respective country.
▶Make sure only trained technicians carry out installation and maintenance work.
▶Secure the product or system to prevent unintentional activation.
▶Do not subject the product to mechanical stress.
▶The Nitrate Sensor is made from stainless steel. Sensors made from stainless steel must be cleaned im-
mediately after coming into contact with salt water or other corrosive substances (e.g acids, alkalis,
chlorine-based connections).
▶The material resistance must be checked after every use.
▶The sensor has seals made from NBR (nitrile butadiene rubber). Sealing rings made from other materials
may be used upon individual request. Before operation, ensure that the measured medium does not
damage the seals.
▶Do not cut, damage or change the cord. Make sure there are no heavy objects on the cable and that the
cable is not folded. Make sure that the cable is not anywhere near hot surfaces.
▶If the sensor cable is damaged, then it must be replaced with an original part by the Bürkert Customer
Service.
▶Do not place unsuitable items in the optical path as long as the measurement process is running, as this
can cause damage to the sensor or incorrect measurement results.
▶Stop operation of the sensor in the event of excessive heat development (i.e. if it is hot to the touch).
Switch off the sensor immediately and unplug the power cord from the power supply. Please contact
your dealer or the Bürkert Customer Service.
▶After an interruption in the power supply, make sure that the process is restarted in a controlled manner.
▶Never try to disassemble or modify the product or a part of the product if such a procedure is not expli-
citly described in this manual.
▶Products from Bürkert meet the highest safety standards. Inspections, modifications and repairs to the
product, which involve the replacement of the connecting cable, must be carried out by Bürkert or by a
workshop /qualified experts authorized by Bürkert. Defective, improper repairs can lead to accidents
and injuries
▶Observe the general rules of technology.
DANGER!
Injuries due to UV light
▶Never look directly at the light source. The radiation emitted (UV light) can cause serious damage to the
eyes.
DANGER!
Handling with reagents and liquid waste
▶Follow the safety and operating instructions of the manufacturer when using reagents. Observe the valid
Hazardous Materials Ordinance for reagents.
▶Liquid waste may be a biohazard. Always wear gloves when working with such materials. Observe the
currently valid biological agents regulation.
▶When handling liquid waste, observe the regulations on water pollution, drainage and waste disposal.

Type MS09
Safety instructions
12
DANGER!
Bürkert does not guarantee the plausibility of the measured values. The user is always responsible for the
monitoring and interpretation of the measured values.
CAUTION!
Electrostatically sensitive components and assemblies.
The product contains electronic components that are susceptible to the effects of electrostatic dischar-
ging (ESD). Components that come into contact with electrostatically charged persons or objects are at
risk. In the worst case scenario, these components are destroyed immediately or fail after start-up.
▶Meet the requirements specified by EN 61340-5-1 to minimize or avoid the possibility of damage caused
by sudden electrostatic discharge.
▶Do not touch electronic components when the supply voltage is connected.

Type MS09
Product description
13
3 PRODUCT DESCRIPTION
3.1 Design
The MS09 consists of the following components:
1 2 3 4
Fig.1: MS09 components
1 Nitrate Sensor 2 Flow cell
3 Connecting cable 4 ME63 Sensor interface
3.1.1 ME63 Sensor Interface
1
2
3
4
5
6
7
8
9
10
11
12
13
Fig.2: View of ME63 type
1 X1 2 X2
3 X3 4 X4
5 X5 6 X6
7 X7 8 X8

Type MS09
Product description
14
9 Product status indicator 10 Cover with 2 screws, slot for micro SD card
11 X01, X02: D-coded connection 12 X03 (IN), X04 (OUT): L-coded connection,
24 V DC
13 Earth connection
3.1.2 MS09 Nitrate Sensor
Fig.3: View of Nitrate Sensor
Fig.4: Nitrate Sensor dimensions
3.1.3 Flow cell

Type MS09
Product description
15
Fig.5: View of flow cell
62
62
108
M5 x 0,8 20
Fig.6: Flow cell dimensions
3.2 Display elements
Type ME63 has LEDs for diagnostics on the product status:
1
2
3
4
5
Fig.7: Display elements for ME63 type
1 Product status indicator. The indicator op-
erates according to NAMUR NE 107.
2 Communication status indicator 1. The in-
dicator changes between green and red.
3 Link/Act Blinking - There is activity on this
port. Off - No link is etablished
4 Communication status indicator 2. The in-
dicator changes between green and red.

Type MS09
Product description
16
5 Link/Act Blinking - There is activity on this
port. Off - No link is etablished
3.2.1 Product status indicator
The product status indicator changes its colour based on the NAMUR recommendation NE107.
The colour of the product status indicator gives the following pieces of information:
▪Whether product diagnostics are active or not. Diagnostics are active on the product and cannot be de-
activated.
▪If product diagnostics are active, then the product status indicator shows whether diagnostics events
have been generated or not. If several diagnostics events have been generated, then the product status
indicator shows the diagnostics event with the highest priority. Refer to table [}16]
If the product status indicator flashes, then the product is selected in a man-machine interface such as the
Bürkert Communicator software.
Colour 1Colour code (for a
PLC)
Diagnostics event 1
Red 5 Failure, error or fault
Due to a malfunction of the product or its periphery.
The functionality of the product is not guaranteed.
Orange 4 Check function
The product is being worked on:
▪The product is searching for a büS participant.
▪This status is exited after a few seconds.
▪Product simulation active.
Yellow 3 Out of specification
The ambient conditions or process conditions for the product are outside the spe-
cified ranges.
Product internal diagnostics point to problems in the product or with the process
properties.
Data sheet values cannot be complied with.
Blue 2 Maintenance required
The product has detected a deviation during ongoing diagnostics and has imple-
mented a correction.
Do the required maintenance operation.
3 Product configuration cannot be managed
The updated product configuration cannot be saved.
It is not possible to transfer the configuration when swapping products.
Green 1 Diagnostics active
Product is in error-free operation.
Status changes are highlighted in colour.
Messages are sent via any fieldbus that may be connected.
1 according to NE107

Type MS09
Product description
17
Colour 1Colour code (for a
PLC)
Diagnostics event 1
White 0 Diagnostics inactive
Product is switched on.
Status conditions are not displayed.
Messages are not listed in the message list or transmitted via any connected field-
bus.
Product is running within its specifications.
Tab.1: Product status indicator in accordance with NAMUR NE107, edition 2006-06-12, for active diagnostics
To solve a problem indicated by the product status indicator, refer to chapter: Troubleshooting [}78].
3.3 Markings
3.3.1 Type label
3.3.1.1 ME63 Sensor Interface
Fig.8: ME63 Label
3.3.1.2 Nitrate Sensor
Fig.9: Nitrate Sensor Label
3.3.1.3 Flow cell
Fig.10: MS09 Flow cell Label

Type MS09
Product description
18
3.3.2 Conformity marking
D-74 6 53 Ingelf ingen
Made i n G ermany
Conformity
marking
Fig.11: CE marking
3.4 Memory Card
A micro SD card (available as an optional accessory) can be used as a memory card to store product-spe-
cific values and user settings and transfer them to another product. Refer to chapter Install the micro SD
card [}35] and Transfer data to or from another product [}36].
CAUTION!
The micro SD card used is a special industrial version that offers additional durability and temperature res-
istance.
▶Do not use a standard micro SD card for the product. Only purchase the micro SD card for the product
from your Bürkert sales department.
Function of the micro SD card limited to data exchange
The micro SD card is not suitable for back-ups. If the micro SD card of the product is re-inserted at
a later stage, then the data last saved are not restored. The function of the micro SD card is limited
to data exchange.
3.5 Operating principle
The ME63 Sensor Interface represents the central control unit for MS08 and MS09.
Function: The ME63 Sensor Interface is an additional interface for büS devices. The ME63 Sensor Interface
exchanges data with the Nitrate Sensor on Ethernet communication.
Measurement principle
For optimal use of the sensor, it is essential to understand the measuring principle and measurement setup
which the sensor is based on. The following is an overview of the measurement principle, the optical ar-
rangement and the subsequent calculation.
1 2 3 4
Fig.12: Operating principle MS09 Nitrate Sensor
1 Light source 2 Reference diode
3 Lens system and optical path 4 Detector
The Nitrate Sensor essentially consists of four parts (see figure above):

Type MS09
Product description
19
▪a defined light source
▪a lens system
▪the optical path through the medium
▪a second lens system with three photodiodes as detectors
A xenon flash lamp is used as a broadband light source. The light passes through the medium in the optical
path and is partially absorbed by it. The photodiodes pick up the remaining light and determine its intensity
at defined wavelength points. The weakening of the light when passing through the measurement medium
is compared to the weakening caused by ultra-pure water. The measurement in ultra-pure water provides
the so-called basic intensity I0. Using equation 1 and equation 2, the Nitrate Sensor determines the trans-
mission T and the absorbance A for three defined wavelengths.
T = I
I0
Fig.13: Equation 1 - Calculation of transmission
A = −log10 T = −log10
I
I0
Fig.14: Equation 2 - Calculation of absorbance
where:
Ttransmission in %
Icurrent light intensity
I0basic light intensity in ultra-pure water
Aabsorption in AUs (AU = absorbance unit)
Analysis
0
0,5
1
1,5
2
2,5
3
190210230250270290310330350
Absorption [AU]
Wavelength [nm]
Nitrate
Nitrite NOx
Organics
SAC254 Turbidity
Fig.15: Detection at wavelengths 212, 254 and 360nm (red arrows)

Type MS09
Product description
20
Parameters
The Nitrate sensor measures absorption at 212nm. The derived parameter NO3 is output.
Taking the path length into account, the absorption values [AU] are calculated with the unit [1/m] at 212,
254 and 360nm. The Nitrate sensor uses the absorption at 212nm for the detection of NO3-N. Absorption
at 254 (SAC254) and 360nm is used to correct organic compounds and turbidity. Optical path lengths of
0.3, 1, 2, 5 or 10mm are available for the Nitrate sensor.
It is possible to adapt the sensor with scaling factors to laboratory analyses and local conditions. Please
note that the manufacturer's calibration is not affected by the customer-specific calibration (refer to chapter
Adjust the measure values (customer calibration) [}42]).
Optimal range Allowed range Out of specification
range
Refer to chapter Main-
tenance [}73]
SQI value 1...0.8 0.8...0.5 <0.5
Tab.2: SQI value range and quality of measurement
Compensation of Turbidity and Organics
Optical nitrate measurement can be influenced by the presence of particles (turbidity) and organic sub-
stances (organics). For this reason, the manufacturer's calibration contains a compensation for turbidity and
organics, as shown schematically in the figure below.
Organics
Nitrate
Organics
Turbidity
Organics
Turbidity Turbidity
Turbidity
compensation
Organic
compensation
212nm 254nm 360nm
In the case of organic compensation, it is possible to choose from three fixed compensations for different
applications:
Default: standard manufacturer calibration.
High: manufacturer calibration with enhanced compensation for high concentrations of organic
substances.
Low: manufacturer calibration with reduced compensation for low concentrations of organic sub-
stances.
Reference values
In addition to NO3, the following reference values are output (refer to chapter Check values for advanced
diagnostics [}50]):
▪The SQI value is the sensor quality index that indicates the quality of the measurement.
▪RefA indicates the light intensity on the 212nm channel.