OTT ecoN Operating Instructions Manual

2 Order numbers and version code 5 3 Basic safety instructions 7 4 Introduction 8 5 Installing the OTT ecoN 10 5.1 Installing in an observation well 11 5.2 Installing with fastening clamps 12 5.3 Installing on a float 13 5.4 Electrical connection 14 6 Setting the operating parameters 15 6.1 Connecting the OTT ecoN to a PC 15 6.2 Calling up the OTT ecoN web interface 16 7 Modbus protocol (RTU) 18 7.1 Prerequisites 18 7.2 "Read Holding Registers" (0x03) / "Write Multiple Register" (0x10) functions 18 7.3 "Write Single Registers" function (0x06) 19 7.4 "Report Server ID" function (0x11) 19 8 Maintenance 20 8.1 Cleaning the OTT ecoN 20 8.2 Checking the OTT ecoN zero point 21 8.3 Calibrating the OTT ecoN 22 8.4 Checking OTT ecoN reference values 23 9 Repairs 24 10 Notes about the disposal of old units 24 11 Technical data 25 12 Measuring range, limits, accuracy depending on path length 26 Appendix A – Dimensions 27 Appendix B – Accessories: Mechanical wiper 28 B1 – Preparing the mechanical wiper 29 B2 – Installing the mechanical wiper on the OTT ecoN 31 B3 – Electrically connecting the mechanical wiper 31 B4 – Changing the wiper blade 33 B5 – Mechanical wiper technical data 34 Appendix C – Note on Declaration of Conformity 35 3

 – 1 Optical UV nitrate sensor (immersion housing), Housing material: stainless steel; Permanently attached connecting cable with M12-connector*, 10 metres; Serial interface: RS-485 with Modbus transmission protocol – 1 Connecting cable with M12-socket* and open ends; 1.5 metres – 1 Calibration certificate 2 Order numbers and version code  OTT ecoN UV Nirate Sensor 63.300.001.9.0 with path length (measuring range): – 0.3 mm –.3 – 1 mm –1 – 2 mm –2 – 5 mm –5 – 10 mm –10  Accessories Mechanical wiper 63.300.010.9.0 – For cleaning the optical path – Without wiper shaft and wiper blades – For mounting on the OTT ecoN housing tube – Permanently attached connecting cable with M8-connector*; 10 metres – Connecting cable with M8-socket* and open ends; 1.5 metres Extension cable for OTT ecoN M12-socket/M12-connector* – 10 metres 63.300.018.9.0 – 25 metres 63.300.019.9.0 Extension cable for mechanical wiper M8-socket/M8-connector* – 10 metres 63.300.016.9.0 – 25 metres 63.300.017.9.0 Connecting cable with open ends for OTT ecoN 63.300.035.9.0 with M12-socket*; 1.5 metres Connecting cable with open ends for mechanical wiper 63.300.036.9.0 with M8-socket*; 1.5 metres Fastening clips for OTT ecoN 63.300.031.9.0 66 mm x 86 mm; black; including mounting accessories Float for OTT ecoN 63.300.030.9.0 for horizontal installation in surface waters with fluctuating water level (alternative to fixed, suspended vertical installation) * The M12/M8 connectors are not pressure water tight ¨ not suitable for use under water! Protection: IP67 OTT ecoN

– 10 mm 63.300.032.9.0 – 50 mm 63.300.033.9.0 G2 Interface Box for configuring the OTT ecoN via a local network (LAN, Local Area Network); Ethernet interface (RJ45 socket); optional WLAN; OTT ecoN connection via M12 socket – with WLAN connection 63.300.020.9.0 – without WLAN connection 63.300.021.9.0 Operating instructions – German 63.300.001.B.D – English 63.300.001.B.E – French 63.300.001.B.F – Spanish 63.300.001.B.S  Set of wiper blades (5 pcs.) including compatible wiper shaft, mounting accessories, lubricating grease and tool – for 1 mm path length 63.300.011.9.0 – for 2 mm path length 63.300.012.9.0 – for 5 mm path length 63.300.013.9.0 – for 10 mm path length 63.300.014.9.0 Optical cleaning set 63.300.034.9.0 – Dropper bottle with acetone – Cleaning wipes for optical lenses, 50 pcs. – Plastic pliers Spare parts/ consumables 6

 Read these operating instructions before commissioning the OTT ecoN. Ensure you are thoroughly familiar with how to install and operate the OTT ecoN. Retain these operating instructions for subsequent reference.  The OTT ecoN is used for continuous measurement of the nitrate content of ground and surface water. Measurement in water with a salt content of > 1 PSU is not possible. Only use the OTT ecoN as described in these operating instructions. For further information ¨ see Chapter 4, Introduction.  Observe all detailed safety instructions specified for the individual work steps. All safety instructions provided here are indicated by a warning symbol placed next to them.  Note that the OTT ecoN may only be installed by a trained specialist (e.g. electrician). For further information ¨ see Chapter 5, Installing the OTT ecoN.  Ensure compliance with the electrical, mechanical and climatic specifications set out in the technical data. For further information ¨ see Chapter 11, Technical Data.  Do not make any changes or modifications to the OTT ecoN. Changes or modifi- cations invalidate all warranty entitlements. In addition, the radio approval neces- sary for operation is invalidated.  Only have a defective OTT ecoN inspected and repaired by our repair centre Never repair it yourself. For further information ¨ see Chapter 9, Repairs.  After decommissioning, dispose of the OTT ecoN properly. Never dispose of the OTT ecoN with normal household waste. For further information ¨ see Chapter 10, Instructions for disposal of used equipment. 7

nitrate content of ground and surface water. The following nitrate concentrations in water can be determined:  NO3-N  NO3  NOX-N 1) (calibrated with standard NO3 solution)  NOX 1) (calibrated with standard NO3 solution) Figure 1 provides a schematic illustration of the measuring principle: A Xenon flash lamp acts as a broad band light source. The light beam first passes through an initial lens system, then passes through the measuring medium (water) in the optical path, followed by a second lens system and is then received by three detectors, which are photo diodes equipped with wavelength-specific filters. The light beam at a wavelength of 212 nm is attenuated according to the nitrate con- tent in the measuring medium. A reference diode before the optical path deter- mines the unattenuated light output. This compensates for a fluctuating or deterio- rating light source output. The additional attenuations measured at wavelengths of 254 nm and 360 nm also enable the OTT ecoN to compensate for organic inter- ference or turbidity of the water. To cover a nitrate measuring range of 0 to almost 900 mg/L with high precision and resolution, the OTT ecoN is available with six different optical path lengths (= measuring ranges; 0.3 - 10 mm). The electrical connection to a data logger or a controller is via the permanently installed connecting cable with M12 industrial connector. An RS-485 interface with Modbus (RTU) transmission protocol is available for this purpose. The nitrate sensor is equipped with an integrated web interface for setting the operating parameters on the OTT ecoN. To use this, the OTT ecoN must be tem- porarily connected to a PC using an interface box. Any internet browser can be used as the user interface. The measuring windows are equipped with anti-fouling technology with nano-coat- ed glass keeping the windows largely free of dirt deposits. At problematic measur- ing points with high organic interference, the nitrate sensor can also be fitted with a mechanical wiper. The wiping movements can be set to any time interval (externally controlled). 1) Combined value for nitrate and nitrite, where both nitrate and nitrite are present in the water to be measured. Differentiation between nitrate and nitrite is not possible with the OTT ecoN. The combined values can be internally scaled using a factor if required. Fig. 1: Optical measuring principle of the OTT ecoN UV Nitrate Sensor. Light source (Xenon- flash light) Reference diode Optical path Optical lenses Detectors (3 x) 8

attached to a suitable substrate with fastening clips or attached to a float. Maintenance work, cleaning, zero point checking and checking the reference values / quality index can be carried out by support staff themselves. The nitrate sensor can be calibrated either in the factory by the OTT repair centre or by trained specialist personnel with the appropriate equipment. Optical path Housing tube (top) Housing tube (bottom) Measuring window Mounting rod Shackle Connecting cable Fig. 2: Overview of OTT ecoN UV Nitrate Sensor.

The OTT ecoN can be installed in three different ways depending on the specific application:  suspended in an observation well see 5.1  attached to a suitable substrate with fastening clips see 5.2  attached to a float see 5.3 With all installation types, note the following:  the optical path must always be completely under water;  there must be an unobstructed inflow of water in the optical path;  the inflow direction should be at right-angles to the optical path (see Figure 3);  the connecting cable may not be used for attaching or suspension; it may not be subjected to any mechanical load in addition to its own weight!  contact between the sensor and the ground is to be avoided; risk of damage.  installation should be carried out in such a way that the OTT ecoN can be tem- porarily uninstalled for maintenance without excessive work;  the measuring windows must be completely free of air bubbles after immersion;  the salt content of the water to be measured may not exceed 1 PSU 1) ¨ no measurement is possible in seawater, brackish water, mining waste water with a high salt content, ... . 1) 1,77 mS/cm at 20 °C Fig. 3: Inflow direction. 10

 Suspend the OTT ecoN on a non-corroding chain or a stainless steel cable. To do this, attach the chain/cable to the mounting rod with a shackle.  Suspend the connecting cable on the chain/cable with an ISO anchor clamp or with cable ties. Recommended minimum diameter of observation well: 4 inches. Fig 4: Suspending the OTT ecoN in an observation well. 11

 Attach the OTT ecoN to a suitable substrate with fastening clips and the enclosed installation accessories (see "Accessories"). Attach the fastening clips as closely as possible to the ends of the sensors. The substrate should be non- corroding.  Attach the connecting cable with cable clamps or install in a cable duct. Fig. 5: Installing the OTT ecoN with fastening clamps. 12

This is the preferred installation type for surface water with significant fluctuations in the water level  Attach the OTT ecoN to the float (see "Accessories") as shown in Figure 6. Attach the fastening clamps as closely as possible to the ends of the sensors.  Secure the float against drifting with non-corroding chains or stainless steel cables.  Attach the connecting cable to the chain/cable with cable ties. Fig. 6: Installing the OTT ecoN on a float. 13

 Supply voltage + 12 … + 24 VDC (±10 %)  Power consumption max. 7 W Notes:  Before electrical connection to a data logger/controller, the OTT ecoN operating parameters must be set; see Chapter 6.  Do not shorten the OTT ecoN connecting cable or remove the M12 connector. Connect using the connecting cable with open ends and M12 socket (see "Accessories").  For cable lengths > 10 meters (with extension cable), the supply voltage must be + 24 VDC (voltage drop). Risk of damage to the OTT ecoN  The supply voltage must be connected with the correct polarity. Check this before applying the supply voltage.  Connect the connecting cable with open ends (M12 socket) to the OTT ecoN connecting cable (M12 connector). Please note: The M12 industrial connectors are not pressure water tight ¨ Not suitable for use under water (degree of pro- tection: IP 67).  Connect the red wire to the supply voltage (+12 … 24 VDC).  Connect the blue wire to earth (GND).  Connect the brown wire to the RS-485 (B) interface on a Modbus master.  Connect the white wire to the RS-485 (A) interface on a Modbus master.  If required: connect braided shield.  With electrically isolated OTT ecoN and Modbus master voltage supplies: Also loop the earth (GND) connection through to the RS-485 interface. The OTT ecoN is ready to operate as soon as the supply voltage is switched on. Note: When connecting an OTT ecoN that is not continuously supplied with voltage to an OTT netDL, a boot up time of 90 seconds is required! Fig. 7: Wire assignment in connecting cable with open ends. Connecting cable red +12 … +27 VDC blue GND brown RS-485 D+ (B) white RS-485 D– (A) not used Braided shield 14

The sensor is equipped with an integrated web interface for setting the operating parameters on the OTT ecoN. To use this, the OTT ecoN must be temporarily con- nected to a PC using an interface box (see "Accessories"). Any internet browser can be used as the user interface. 6.1 Connecting the OTT ecoN to a PC Required accessories:  Power adapter 1)  RJ45 patch cable (Ethernet cable) 1)  G2 interface box 1) included with the G2 interface box Note: When setting the operating parameters, the voltage supply to the OTT ecoN comes from the G2 interface box.  Connect the M12 connector on the OTT ecoN connecting cable to the G2 inter- face box.  Connect the power adapter to the G2 interface box and plug into a mains outlet.  Wait for 3 seconds.  Connect the G2 interface box to a free Ethernet port (RJ45 socket) on a PC using the RJ45 patch cable. (Alternatively, connection using an Ethernet switch or router with DHCP server is possible.) Fig. 8: Connecting the OTT ecoN to a PC. 15

Note: The Ethernet interface on the PC must be configured to automatically obtain the required network settings (DHCP protocol).  Start any internet browser on the PC.  In the browser, enter one of the following: – http://ecoN.ott/ – http://ecoN_serial number/ – http://192.168.77.1/ and press enter ¨ The home page of the OTT ecoN user interface opens (in English). Web interface menu structure  "Overview" – Information about the OTT ecoN – Information about the Xenon flash lamp  "Calibration" – This function is reserved exclusively for OTT service personnel or specially trained users; "Login" and "Password" required  "Data Logger" – Simple, internal data logger; the sample/storage interval is 30 seconds; – "Clear" clears and formats the internal memory – "Download" copies the measured values recorded in the selected period ("Start date" to "End date") to the PC  "Measurement" – "Parameter": shows the measured results from the last measurement in a table – "Measure now!": starts instantaneous value measurement – "Settings": allows you to enter an offset value and scaling factor and to calculate a sliding mean value over "n" measured values – "Edit" "Comment": enter any informative comments "Automatic": activates/deactivates automatic measurement (must be activated in combination with an OTT netDL or Sutron datalogger!) "Interval [s]": sample/storage interval is 30 seconds;  "Pheripherals" – RS-485 interface parameters; factory default setting: "Modbus RTU", "9600", "none", "none", "1"; – "Address": Modbus address; factory default setting: "1" Fig. 9: OTT ecoN user interface. 16

– "Current Date and Time": internal date and time on the OTT ecoN – "Recovery Point": this function is reserved exclusively for OTT service person- nel or specially trained users; "login"/"password" required – "System Log": Log file containing measurements performed, changes to the operating parameters and error messages. "Download!" copies the log file to the PC. Explanations of reference measured values "Measurement" | "Parameter" function  SQI Sensor-Quality-Index, specifies the quality of a measurement: 1,0 … 0,8 ¨ OK 0,8 … 0,5 ¨ Marginal < 0,5 ¨ Error, see Chapter 8.4  RefA Light intensity on the 212 nm channel; this value should always be higher than 150, otherwise insufficient light reaches the specific detector.  RefB Light intensity on the 254 nm channel; this value should always be higher than 150, otherwise insufficient light reaches the specific detector.  RefC Light intensity on the 360 nm channel; this value should always be higher than 150, otherwise insufficient light reaches the specific detector.  RefD specifies the light intensity of the Xenon flash lamp; this value should always be higher than 13 000. For further information on evaluating the reference measured values, see Chapter 8.4. 17

7.1 Prerequisites  Connection via RS-485 interface  Transmission parameters data bits: 8; parity: none; stop bits: 1 (8N1)  Transmission speed 9600 bps  Operating parameter "Measurement |"Automatic" Combined with OTT netDL: activated Note: When connecting the OTT ecoN to an IP Datalogger OTT netDL, the OTT netDL configuration is limited on using Modbus function "Read Holding Registers" (0x03). 7.2 "Read Holding Registers" (0x03) / "Write Multiple Register" (0x10) functions 1) Byte sequence: AB CD (Big Endian) Register name Register- number Type Value range Factory setting Access- mode Unit  Bus address 0000 unsigned word 1 … 247 1 R/W –  Serial number 0010 unsigned word 10 Byte; ASCII-Format – R –  Firmware version 0015 unsigned word 10 Byte; ASCII-Format – R –  Measured value NO3-N scaled value 1000 1500 float 1) 1 mm: 0.5 … 60 10 mm: 0.05 … 6 R [mg/L]  Measured value NO3 scaled value 1002 1502 float 1) 1 mm: 2.2 … 266 10 mm: 0.22 … 26.6 R [mg/L]  Spectral quality index SQI scaled value 1004 1504 float 1) 0 … 28000 R [1]  Light intensity 212 nm; RefA scaled value 1006 1506 float 1) 0 … 28000 R [1]  Light intensity 254 nm; RefB scaled value 1008 1508 float 1) 0 … 28000 R [1]  Light intensity 360 nm; RefC scaled value 1010 1510 float 1) 0 … 28000 R [1]  Light intensity reference diode, RefD scaled value 1012 1512 float 1) 0 … 28000 R [1] 18

Writing the value "0x0101" into the register "0x0001" starts a single measure- ment. Afterwards the measured values can be read out via function "Read Holding Registers". 7.4 "Report Server ID" function (0x11) This function outputs the sensor name, the serial number and the firmware version each "null terminated". 19

Recommended interval: every 12 months With problematic local measuring point conditions (organic interference or water turbidity): Every 4 to 6 months as required. Tip: After initial instal- lation, check the sensor at short intervals and adjust the cleaning interval according to specific requirements. Required equipment:  soft brush, sponge  mild soap solution  if required: Citric /acetic acid solution (10 %)  if required: Oxalic /ascorbic acid solution (5 %)  lint free cloth / paper cloth / optical wipe  Acetone  Ultra pure water Risk of damage to the OTT ecoN  Do not use any chemicals other than those specified here.  Do not use abrasive cleaning agents or objects.  Clean the measuring window with the utmost care.  Protect the M12 socket on the connecting cable from moisture! CAUTION Risk of injury to the skin/eyes/respiratory system due to acetone and acids Improper handling of acetone and acid can lead to minor to moderately severe injuries, particularly damage to – Skin: Dryness (acetone: degreasing effect) skin changes, skin damage, chemical burns; – Eyes: Cornea damage, irritation, chemical burns; – Respiratory system (inhalation): Irritation, fatigue, headaches, dizziness, nau- sea/vomiting, acetone in higher doses has an anaesthetic effect  Wear laboratory gloves and protective goggles to perform cleaning.  Ensure adequate ventilation and do not inhale acetone vapour!  Uninstall the OTT ecoN.  Clear adherent dirt: Soak the OTT ecoN in a mild soap solution for several hours.  If required: Remove any residual dirt with a soft sponge or brush.  For lime scale deposits: Place the OTT ecoN in a 10 % citric acid or acetic acid solution for approx. 15 ... 30 minutes.  For brown deposits (iron or manganese oxide): Place the OTT ecoN in a 5 % oxalic acid or 10 % ascorbic acid solution for approx. 15 ... 30 minutes.  Thoroughly rinse the OTT ecoN with tap water.  Clean the measuring windows: Soak a lint free cloth/paper cloth/special opti- cal wipe with a few drops of acetone (see "Accessories") and carefully wipe off both measuring windows; see Figure 10. 20

pure water.  Allow the OTT ecoN to dry.  Polish the measuring windows with a dry lint free cloth/paper cloth/special optical wipe.  Recommendation: Check the zero point; see Chapter 8.3.  Re-install the OTT ecoN, see Chapter 5. 8.2 Checking the OTT ecoN zero point Recommended interval: after each cleaning; earlier if implausible measured values occur Required accessories:  VALtub 10 or 50 mm length; see "Accessories"  Alternative to VALtub: Suitable clean vessel in which the OTT ecoN can be placed in a slightly inclined position  Ultra pure water (≥ 18,2 MΩcm) Ambient temperature: 20 °C Ultra pure water temperature: 20 °C Note After cleaning the OTT ecoN, do not touch the measuring windows or the housing in the area of the optical path. Wear clean laboratory gloves to check the zero point. If impurities are detected in the ultra pure water when checking the zero point, the water must be replaced. Fig. 10: Cleaning the OTT ecoN measuring windows. 21

 Connect the OTT ecoN to the PC; see Chapter 6.1.  Fit a compatible VALtub on the OTT ecoN housing tube, see Figure 8.  Pour ultra pure water into the VALtub. The measuring windows must be com- pletely under water.  Pour away the ultra pure water after approx. 10 minutes.  Pour fresh ultra pure water into the VALtub; the measuring windows must again be completely under water. There may not be any air bubbles on the measur- ing windows.  Call up the OTT ecoN web interface, see Chapter 6.2.  Perform a measurement: Call up the "Measurement" | "Parameter" | "Mea- sure now!" ¨ the OTT ecoN starts a measurement and displays the result in the browser window. If the measured values are lower than  4.0 mg/L NO3-N with 1 mm path length  0.4 mg/L NO3-N with 10 mm path length the zero point is OK! If the values are equal to or higher than that figure, the OTT ecoN needs to be recalibrated, see Chapter 8.3! 8.3 Calibrating the OTT ecoN The nitrate sensor can be calibrated either in the factory by the OTT repair centre or by trained specialist personnel with the appropriate equipment. For calibration, directly contact the OTT Hydromet GmbH repair centre (see Chapter 9) or the sales office responsible for your area. Fig. 8: Checking the OTT ecoN zero point – VALtub. 22

The OTT ecoN has 5 reference measured values, which can be used to check correct functioning of the device: Sensor-Quality-Index: – SQI Light intensities: – RefA (Wavelength 212 nm) – RefB (Wavelength 254 nm) – RefC (Wavelength 360 nm) – RefD (Reference diode) For detailed information on the reference measured values, see Chapter 6.2. Recommended checking interval: if implausible measured values occur.  RefD < 13 000? The light intensity of the xenon flash lamp is too low (ageing process) ¨ Send the OTT ecoN to the OTT Hydromet GmbH repair centre.  RefD > 13 000 and RefA, RefB, RefC < 150? ¨ Take sensor out of water and perform measurement with air Values identical? ¨ Thoroughly clean sensor, see Chapter 8.1 and measure with air again Values identical? ¨ Check zero point, see Chapter 8.2. Values identical? ¨ Send OTT ecoN to OTT Hydromet GmbH repair centre; see Chapter 9  In ultra pure water: RefA, RefB, RefC = RefD ± 5000 ¨ OK  In ultra pure water: RefA, RefB, RefC = RefD ± 5000 and in measuring medium: RefA, RefB, RefC < 150 ¨ Send OTT ecoN to OTT Hydromet GmbH repair centre; see Chapter 9.

yourself using Chapter 8.4. „Checking OTT ecoN reference values“.  If the device has a defect, please contact the OTT repair centre: OTT Hydromet GmbH Repaircenter Ludwigstraße 16 87437 Kempten · Germany Phone +49 831 5617-433 Fax +49 831 5617-439 [email protected] Please note: Only have a defective OTT ecoN checked and/or repaired by the OTT repair center Never attempt to repair the unit yourself. Any repairs or attempted repairs carried out by the customer will void any warranty. 10 Notes about the disposal of old units Within the member countries of the European Union In accordance with the European Union guideline 2002/96/EC, OTT takes back old devices within the member countries of the European Union and disposes of them in an appropriate way. The devices concerned by this are marked with the symbol shown aside.  For further information on the return procedure, please contact your local sales contact. You will find the addresses of all sales partners in the internet on „www.ott.com“. Please take into consideration also the national implementation of the EU guideline 2002/96/EC of your country. For all other countries  After decommissioning, dispose of the OTT ecoN properly.  Observe the regulations applicable in your country for disposal of electronic devices!  Never dispose of the OTT ecoN with normal household waste. Materials used see Chapter 11 and Appendix B5 24

Measuring technology Ligth source Xenon flash lamp Detector 4 photo diodes + filter Measurement principle Attenuation (optical attenuation) Optical path 0.3 mm 1 mm 2 mm 5 mm 10 mm Parameter NO3-N NO3 NOX-N NOX (calibrated with NO3 standard solution) Measuring range 0.3 mm optical path 1.65 … 200 mg/L NO3-N 1 mm optical path 0.5 … 60 mg/L NO3-N 2 mm optical path 0.25 … 30 mg/L NO3-N 5 mm optical path 0.1 … 12 mg/L NO3-N 10 mm optical path 0.05 … 6 mg/L NO3-N Measuring accuracy 0.3 mm optical path ±(5 % + 3.3 mg/L) NO3-N 1 mm optical path ±(5 % + 1.0 mg/L) NO3-N 2 mm optical path ±(5 % + 0.5 mg/L) NO3-N 5 mm optical path ±(5 % + 0.2 mg/L) NO3-N 10 mm optical path ±(5 % + 0.1 mg/L) NO3-N Turbidity compensation Yes Data logger ~ 2 GB T100 Response Time 20 s Measurement interval ≥ 10 s Housing material Stainless steel (1.4571/1.4404) Dimensions (L x Ø) Approx. 470 x 48 mm (with 10 mm path) Weight Approx. 3 kg Interfaces digital Ethernet (TCP/IP) RS-485 (Modbus RTU) Power consumption ≤ 7 W Power supply 12 … 24 VDC (±10 %) Maintenance effort typ. ≤ 0.5 h/month Calibration/maintenance interval 24 months System compatibility Modbus RTU Max. pressure with Subconn 30 bar with fixed cable 3 bar Protection type IP68 Sample temperature +2 … +40 °C Ambient temperature +2 … +40 °C Storage temperature –20 … +80 °C Inflow velocity 0.1 … 10 m/s 25

Path length Measuring parameter Measuring range Detection limit Determination limit Precision Accuracy 1) [mm] [mg/L] [mg/L] [mg/L] [mg/L] [mg/L] 0.3 Nitrate NO3-N 0 … 200 1.65 4.95 0.495 ±(5 % + 3.3) Nitrate NO3 0 … 886 7.26 21.78 2.178 ±(5 % + 14.5) 1 Nitrate NO3-N 0 … 60 0.5 1.5 0.15 ±(5 % + 1) Nitrate NO3 0 … 266 2.2 6.6 0.66 ±(5 % + 4.4) 2 Nitrate NO3-N 0 … 30 0.25 0.75 0.075 ±(5 % + 0.5) Nitrate NO3 0 … 133 1.1 3.3 0.33 ±(5 % + 2.2) 5 Nitrate NO3-N 0 … 12 0.1 0.3 0.03 ±(5 % + 0.2) Nitrate NO3 0 … 53 0.44 1.32 0.132 ±(5 % + 0.88) 10 Nitrate NO3-N 0 … 6 0.05 0.15 0.015 ±(5 % + 0.1) Nitrate NO3 0 … 26,6 0.22 0.66 0.066 ±(5 % + 0.44) 1) Relative to a standard calibration solution; comment: 1 mg/L NO3-N corresponding to 4.43 mg/L NO3 26

OTT ecoN UV nitrate sensors with path lengths (measuring ranges) of 1, 2, 5 and 10 mm can be equipped with an optional mechanical wiper (see "Accessories") for cleaning the optical path. Depending on the path length, a corresponding wiper shaft and a wiper blade are required (see "Spare parts/consumables"). The wiping operation (duration: approx. 2 ... 3 seconds) is started by connecting the supply voltage. This causes a wiper blade fitted with several rubber lips to rotate twice through the optical path and remove any deposits on the measuring windows of the OTT ecoN. The wiper blade then moves to a park position outside the optical path. To start another wiping operation, the supply voltage must be disconnected for at least 1 second. The mechanical wiper is installed by fitting and screwing two housing sections onto the OTT ecoN housing tube. The mechanical wiper has a separate, permanently installed connecting cable with M8 industrial connector; length: 10 metres. To connect to the supply voltage, a corresponding connecting cable (length: 1.5 metres) with open ends and M8 sock- et is available (see "Accessories"). Fig. B1: Mechanical wiper, installed on housing tube of OTT ecoN UV nitrate sensor. 28

This requires a wiper blade set appropriate for the path length (measuring range) of the OTT ecoN; see "Spare parts/consumables". Risk of damage to the OTT ecoN  Observe the path length of the OTT ecoN: only install a corresponding wiper shaft with associated wiper blade. Installing the wiper shaft and wiper blade:  Lightly grease the O-ring on the wiper shaft with the lubricating grease supplied.  Align the wiper shaft and insert in the hole. If necessary, slightly rotate the wiper shaft so that it can be fully inserted. The O-ring must then be located inside the hole. Fig. B2: Installing the wiper shaft. O-ring Recess Wiper shaft Hole Torx-key Cover Fig. B3: Wiper shaft installed. 29

supplied.  Align the wiper blade (see figure) and slide it onto the wiper shaft until it locks into place (clicking sound). Fig. B4: Attaching the cover. Wiper blade Fig. B5: Fitting the wiper blade. 30

 Align the lower housing section (holes must line up) and place on the housing tube of the OTT ecoN.  Attach the lower housing section to the OTT ecoN using the adjusting screw.  Fit the upper housing section on the OTT ecoN housing tube and attach using the four hexagon socket screws supplied (size: 2.5 mm). B3 – Electrically connecting the mechanical wiper The connecting cable for the mechanical wiper is factory assembled for connection to a switched supply voltage. Switching on the supply voltage starts the wiping operation. If necessary, you can alternatively supply the mechanical wiper with a constant voltage and start the wiping operation using a short trigger pulse. Operating parameters for mechanical wiper:  Supply voltage +12 … + 24 VDC  Power consumption max. 6 W  Wiping operation duration approx. 2 to 3 seconds  Gap between two wiping operations > 1 second  Recommended wiping interval 1 x daily  Trigger pulse length 100 ms  Trigger signal voltage range +5 … + 24 VDC Note: The supply voltage must be applied until the end of a wiping operation. A wiping operation is made up of two wiping cycles. The wiper blade is then in park position. Otherwise the wiper blade may still be in the optical path, which leads to unusable measurements. Fig. B6: Installing the mechanical wiper on the OTT ecoN. Adjusting screw Lower housing section Hexagon socket screw (4 x) Upper housing section Holes 31

wiper connecting cable (M8 connector). Please note: The M8 industrial con- nectors are not pressure water tight ¨ Not suitable for use under water (degree of protection: IP 67).  Connect the brown/white wire to the switched supply voltage (+).  Connect the blue/black wire to earth.  Alternative (with trigger pulse): – Remove double wire end ferrules; – Fit four individual wires with wire end ferrules; – Connect the brown wire to the continuous supply voltage (+); – Connect the blue wire to earth; – Connect the white wire (+) to a controller with trigger output; – Connect the black wire (-) to a controller with trigger output.  Testing the wiping operation: Connect the supply voltage (alternatively trigger pulse) ¨ The wiper blade must rotate twice through the optical path; the rub- ber lips of the wiper blade must slide over both measuring windows with light contact. The wiper blade must then move to the park position. +12 … +24 VDC Earth Fig. B7: Wire assignment in connecting calbe with open ends. 32

Check the wiper blade at regular intervals. If there are any signs of scoring or material abrasion on the rubber lips, it must be replaced. A wiper blade set contains 5 wiper blades (see "Spare parts/consumables"). When all wiper blades in a set are worn, you need a new set as in this case the wiper shaft, O-ring and cover also need to be replaced. (The mechanical wiper does not need to be detached from the OTT ecoN.) Risk of damage to mechanical wiper (gearing)  Avoid mechanical loads on the wiper shaft and the wiper blade!  Never turn the wiper shaft by hand.  At every fifth wiper blade change: First uninstall the entire wiper shaft and then install a new one; see Appendix B2.  Slightly lift the locking mechanism with a fingernail or a small slotted screwdriv- er and pull the wiper blade forwards.  Align the new wiper blade (see Figure B8) and slide it onto the wiper shaft until it locks into place (clicking sound). Locking mechanism Wiper blade Wiper shaft Fig. B8: Changing the wiper blade. 33

Supply voltage 12 … 24 VDC (± 10 %) Power consumption active approx. 2 … 6 W Standby 1) ≤ 30 mW For use with path lengths 1 mm 2 mm 5 mm 10 mm Positive operating pressure max. 3 bar Degree of protection IP 68 Inflow speed max. 10 m/s Operating temperature +2 … +40 °C Storage temperature –10 … +70 °C Actuation Connecting cable fixed connection, 10 metres; with 4-pin M8- connector + connecting cable with M8-sock- et and open ends; 1.5 metres Trigger input 5 … 24 VDC (±10 % ) Trigger input power consumption 2 … 15 mA Wiper operation duration ≤ 3 seconds Dimensions L x Ø 175 mm x 80 mm Weight 0.52 kg Materials NBR, POM, TPE (PP, EPDM), V4A 1) For continuously applied supply voltage and actuation using trigger signal 34

If necessary, you can download the current version of the Declaration of Conformity for the OTT ecoN from our website as a PDF file: "www.ott.com/resources". 35

Ludwigstrasse 16 87437 Kempten · Germany Telefon +49 831 5617-0 Telefax +49 831 5617-209 [email protected] · www.ott.com