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Copyright ©2022 Geolux d.o.o. All rights reserved.

GLX-RSS-2-300 WL

Non-Contact Flow Meter

User Manual

v6.4.8

Summary of Contents for GLX-RSS-2-300 WL

Page 1: ...Copyright 2022 Geolux d o o All rights reserved GLX RSS 2 300 WL Non Contact Flow Meter User Manual v6 4 8 ...

Page 2: ...y freely rely on our field proven radar technology The use of top quality components and advanced signal processing algorithms ensures that Geolux level meter can be used in various applications and environments We have created this User Manual to assist you in setting up and using the Geolux instrument Should there be any questions left unanswered please feel free to contact us directly Geolux d ...

Page 3: ... 11 5 Radar Settings 13 6 Data Interface 24 6 1 Serial RS 232 Interface 24 6 2 Serial RS 485 Interface 24 7 Data Protocols 25 7 1 NMEA Protocol RS 232 25 7 2 Servicing Protocol RS 232 28 7 3 Request Response Protocol RS 485 36 7 4 HS Protocol 36 7 5 Modbus Protocol RS 485 37 7 6 SDI 12 43 8 Radar Configurator Utility 47 8 1 Configuring the Unit for Discharge Calculation 51 8 1 1 Defining the Chann...

Page 4: ... the distance between the sensor and the water surface The radio signal modulation and detection algorithms used in the sensor allow very precise measurements that are not dependent on air temperature humidity or other parameters of the environment The flow meter is able to detect water surface velocity ranging from 0 02 m s to 15 0 m s with precision of 0 001 m s while the distance can be measure...

Page 5: ...n height above the water 24 075 108 0 02 0 001 24 125 110 12 24 1 24 175 20 112 15 0 15 GHz dBm dBm m s m s m Radar Level Sensor Frequency Beam width 3dB Azimuth Beam width 3dB Elevation Resolution Accuracy Minimal distance Maximal distance 77 000 0 5 0 2 5 2 5 5 2 5 2 81 000 15 30 GHz mm mm m m Power supply voltage 9 0 12 0 27 0 V Power Operational mode Sleep mode 1550 85 mW mW Alarm Output Maxim...

Page 6: ...wn Vin The power supply for the Radar Speed Sensor is provided on this pin The Radar Speed Sensor pow er supply voltage must be in the range 9 VDC to 27 VDC and the power supply must be able to provide at last 0 65W 3 Green RS232 TxD RS 232 data transmit signal 4 Yellow RS232 RxD RS 232 data receive signal 5 Grey GND Signal ground 6 Pink CAN H CAN2 0B high signal optional 7 Blue CAN L CAN2 0B low ...

Page 7: ...must be specified when ordering the sensors Several communication protocols are available as well as custom ones on request Details of communication protocols are described in chapter 7 of this user manual Picture 1 Serial RS232 DB 9 Cable 3 2 Serial RS 485 Interface Serial RS 485 interface is implemented as standard industrial half duplex communication interface Communication interface is interna...

Page 8: ...round Maximal voltage applied to the sink can go up to 30 VDC providing greater flexibility in connections of the sensor to PLCs loggers or data concentrators Signal range and function for 4 20 mA analog output can be configured in the setup application so the sensor will be able to signal the best suitable value range with available current range Current step in the sensor is 0 3 µA which limits ...

Page 9: ...face is widely used to connect hydrological equipment to dataloggers SDI 12 uses a single communication line and very slow speed communication to enable the use of very long communication cables For hydrological applications SDI 12 communication interface is a valid option and the instrument is natively able to communicate directly with SDI 12 master devices dataloggers etc ...

Page 10: ...ny other objects or structures 4 1 Instrument Mounting and Location Selection To achieve the specified accuracy it is important to properly select the measurement site and to install the sensor with proper horizontal and vertical tilt angle For optimal operation and best results the instrument should be oriented in parallel with the water flow direction Any deviation from parallel water flow direc...

Page 11: ...r flow to give stable measurements even under turbulent conditions However even the moderate waviness of the water surface will improve the measurement if the water flow is strongly turbulent fluctuations in measured data could be expected as well as somewhat reduced measurement accuracy If strongly turbulent flow can be expected at monitoring site then the filter length of the radar should be con...

Page 12: ...ement quality The quality indicator value ranges from 0 best quality to 3 worst quality and can be used to interpret the data in the analysis software with better understanding and confidence For example when the radar is mounted on the railway bridge one of common applications the measurement quality will be very good most of the time except when a train is passing due to the extensive vibrations...

Page 13: ...hase noise of the internal oscillator is very good and is always trimmed in the factory to a precise central frequency but even with the best possible trimming and most stable oscillators it is very unlikely that two devices will be working on the exact same frequency to cause interference Doppler frequency shift caused by water in speed range up to 15 m s is measured in kHz frequency shift As thi...

Page 14: ...h conditions 4 6 Reflections Water reflects radar signals very well which means most of the power of a wave transmitted from the radar transmitter will be reflected from the surface of the water Reflections of the radar beam transmitted power follow the same physical laws as in optics and every time the radar beam hits the water surface part of the power is reflected away from the radar part of th...

Page 15: ...oving objects grey cloud Such additional radar reflections can significantly affect measurement accuracy Installations where pedestrians cars or other objects are moving in front of the sensor closer than 75 meters should be avoided as it is proven in practice that it can cause problems Indoor applications are generally not recommended as it could lead to wrong readings due to the reflection of th...

Page 16: ...ud rate is 9600 bps RS 232 and RS 485 protocol 1 0 0 1 0 ABCD Protocol RS232 and RS485 RS 232 protocol Selects the communication protocol to be used for data communication on RS 232 interface The NMEA protocol is a GPS like human readable messaging protocol where each data packet contains a checksum for data integrity verification RS 485 protocol Selects the communication protocol to be used on RS...

Page 17: ...r detection When parity is set to None no parity is used and no error detection is possible on bit level When parity is set to Odd parity an additional bit is added to the communication that will be set to 1 when there is an odd number of bits with value 1 in the 8 bit payload byte Similarly when parity is set to Even parity an additional bit is added to the communication that will be set to 1 whe...

Page 18: ...x 4 20 mA min To configure the 4 20 mA output range the minimum measured value which will correspond to 4 mA analog output needs to be set The value is set in the currently configured measurement unit Example if values measured by the instrument are expected to be within the range of 700 mm s up to 1500 mm s it is recommended to configure the minimum value to slightly below 700 mm s for example 50...

Page 19: ...atively if the resolution is not critical then the minimum value for 4 20 mA output can be left to the instrument minimum of 0 mm Level 4 20 mA max To configure the 4 20 mA output range the maximum measured value which will correspond to 20 mA analog output needs to be set The value is set in the currently configured measurement unit Example if values measured by the instrument are expected to be ...

Page 20: ...any flow Setting SNR threshold to a higher value will result with more robust measurements but may also result with no measurements when the water is very smooth Generally measurements with SNR below 10 dB may be inaccurate and measurements with SNR below 6 dB should not be trusted The SNR threshold should be set accordingly Filter Length Filter length The length of the averaging filter in number ...

Page 21: ...then the measured data No filter No filtering is used and the raw measurements are reported IIR Infinite Impulse Response filter is used to smooth the data When compared to moving average filter IIR filter reacts more quickly to initial change in the data but it takes longer for the smoothed value to reach the new measurement The use of IIR filter is discouraged for general applications The IIR co...

Page 22: ...sed for filtering and the resulting data will be smoother However when the water level changes it will take more time for the new measurement to be reported Typically this parameter should be set to a value between 10 and 50 For highly turbulent water longer filter length is recommended IIR Constant IIR constant The constant used by Infinite Impuls Response IIR filter if IIR filter type is selecte...

Page 23: ...ce equal to 0 The threshold is used to filter noise and false readings and it is recommended to keep this value between 0 and 1000 Peak Detector Type Peak detector type Configuring the type of algorithm which is used to detect the peaks in the radar echo curve The default setting should be Maximum peak In specific cases such as when a water level needs to be measured but there is a lot of vegetati...

Page 24: ... unit The measurement unit used to report the measured level value The default measurement unit is millimetres When changing the measurement unit it s important to make sure that other parameters which depend on the measurement unit such as active zone parameters are also changed to the new unit PGA sensitivity PGA sensitivity This parameter limits the maximum gain amplification level of the inter...

Page 25: ...le distance between the water and the instrument at the specific monitoring site Typically this is the distance between the instrument and the lowest point in the channel Level sensor height The height of the instrument needs to be set above the water zero level gauge zero The instrument will output relative measurement of the actual water level based on its height above the water zero level Examp...

Page 26: ...and SDI 12 interfaces The device is always available over RS 232 and Modbus interfaces In any SDI12 sleep mode the device remains in the sleep mode until SDI 12 Measure aM command is received While in deep sleep mode the device will not be able to connect to Modbus or RS 232 interface For reconfiguring the device which is set to operate in SDI 12 deep sleep mode it s necessary to power cycle the d...

Page 27: ...top bits 1 Parity None A NMEA like communication protocol is used to deliver flow measurements over RS 232 interface Detailed description of the protocol is given in chapter 7 of this user manual 6 2 Serial RS 485 Interface Serial RS 485 interface is used for connecting multiple flow meters to a single data logger RS 485 interface uses a different protocol then the protocol used over RS 232 interf...

Page 28: ... sentence type NMEA sentences are terminated with the checksum which makes this protocol extremely reliable NMEA protocol is a single direction protocol data is only transmitted from the flow meter At RS 232 interface the device periodically outputs following data sentences Direct flow measurement report RDTGT D1 S1 L1 CSUM CR LF RDTGT The keyword sent in the beginning of each detection report Thi...

Page 29: ...e characters in the report from to excluding these characters Quality of signal report QOS Q1 Q2 CSUM CR LF QOS The keyword sent in the beginning of each quality of signal report Q1 Quality of signal estimate based on sensor vibration Q2 Quality of signal estimate based on radar signal analysis CSUM The check sum of the characters in the report from to excluding these characters Quality of signal ...

Page 30: ...ence plane S1 Measurement SNR in dBm S2 The standard deviation of water level measurements The number of samples used to calculate the standard deviation is equal to the configured filter length CSUM The check sum of the characters in the report from to excluding these characters Level sensor tilt angle report LVLANG A1 A2 CSUM CR LF LVLANG The keyword sent in the beginning of each level sensor ti...

Page 31: ...rs Baud rate Configures the baud rate bits per second for serial communication on both RS 232 and RS 485 data lines This setting controls how many bits are sent on the communication line in one second The available values are standardized Using higher baud rates over longer lines may introduce errors in transferred data The default instrument baud rate is 9600 bps set_baud_rate 9600 set_baud_rate ...

Page 32: ...Warm up time The time after sensor power up during which all measurements are ignored This time is used to settle auto gain parameters Kalman filter values averaging filter and all other operational parameters It is recommended to set this value to a minimum of 5 seconds In extreme cases where a quick response after unit power up is required 3 seconds can be used with a possibility of losing measu...

Page 33: ...A output can be left to the instrument minimum of 0 mm set_lvl_420_max value Level 4 20 mA max To configure the 4 20 mA output range the maximum measured value which will correspond to 20 mA analog output needs to be set The value is set in the currently configured measurement unit Example if values measured by the instrument are expected to be within the range of 700 mm up to 5000 mm it is recomm...

Page 34: ... measurements The length for the moving average filter is configured separately through Filter length parameter Median The median filter finds the median value from a number of raw measurements The length for the median filter is configured separately through Filter length parameter Standard deviation This type of filter is similar to the moving average filter It takes a number of raw measurements...

Page 35: ...e value set_discharge_units m3s set_discharge_units liters set_discharge_units ft3s Velocity unit The measurement unit used to report the measured velocity value For NMEA protocol which is used over RS 232 connection the velocity is reported as an integer value To preserve higher precision with integer numbers the measured velocity will be multiplied by 10 for m s km h mph fps and fpm when being t...

Page 36: ... possible distance between the water and the instrument at the specific monitoring site set_lvl_deadzone_min value Level active zone max This parameter limits the operational range of the instrument The instrument will detect water level only within the range set by the Active zone min and Active zone max parameters This parameter is the best way to filter unwanted radar reflections from other str...

Page 37: ...ry to power cycle the device and then use the Geolux Instrument Configurator PC application to connect to the device within 20 seconds after power up If there is no attempt to connect to the device over RS 232 interface within 20 seconds the device will automatically go back to sleep mode The device consumes only 0 08W while in standby mode and 0 04 W while in sleep mode Device in sleep mode This ...

Page 38: ...0 an420_max 10000 000 min_velocity 0 000 max_velocity 15000 000 level_sensor 2 sdi12_sleep 0 discharge_units liters lvl_firmware 237 lvl_units mm lvl_filter_type 4 lvl_filter_len 15 lvl_deadzone_min 200 000 lvl_deadzone_max 15000 000 lvl_420_min 0 000 lvl_420_max 15000 000 lvl_sensor_height 0 000 lvl_peak_detector 0 lvl_aplitude_threshold 0 ...

Page 39: ...0 0x32 CSUM Checksum calculated by adding in modulo 256 the two byte values of the ID If the device ID is 2 then ID was sent as 0x30 0x32 Checksum is then 0x30 0x32 0x62 After receiving the request if the device ID matches the flow meter will respond with the current averaged flow velocity reading 0xA5 ID SPEED LEVEL CSUM 0xA5 The first byte sent in the response is byte with HEX value of 0xA5 ID E...

Page 40: ...polled unit ID is 2 then ID will be sent as 02 In HEX representation it is the following two bytes 0x30 0x32 CSUM Checksum calculated by adding in modulo 256 the two byte values of the ID If the device ID is 2 then ID was sent as 0x30 0x32 Checksum is then 0x30 0x32 0x62 After receiving the request the device goes from Power save mode to normal Operational mode 7 5 Modbus Protocol RS 485 When conf...

Page 41: ...register CRC16 0X84 CRC Low 0X0A CRC High Table 5 Slave Sensor Response Format Name Address Fun Byte Count Data CRC16 Length 1 byte 1 byte 1 byte 2 bytes H L 2 bytes L H Example 0X01 0X03 0X02 0X00 0X01 0X79 0X84 Table 6 Response Example Name Content Detail Address 0X01 Slave address Sensor id Function 0X03 Read slave info Data Length 0X02 Data length is 2 bytes Data 0X00 Data high byte 0X01 Data ...

Page 42: ... 0 8 Read defined PGA gain sensi tivity 0X0009 2 byte 0 both 1 incoming 2 outgoing Read flow direction filter setting 0000A 2 byte 0 100 Read sensitivity value 0X000B 2 byte 1 Read device type always 1 0X000C 2 byte 0 3840 Read SNR threshold dBm 256 0X000D 2 byte 621 Read firmware code 6 2 1 0x000E 2 byte 1 2 5 10 20 50 100 200 Read current PGA gain level 0x000F 2 byte 0 2047 Read relative signal ...

Page 43: ...ned units 0x0023 2 byte 0 65535 Read distance to water surface decimal part in defined units 0x0024 2 byte 0 65535 Read measured water level integer part in defined units relative to defined staff gauge zero 0x0025 2 byte 0 65535 Read measured water level decimal part in defined units relative to defined staff gauge zero 0x0026 2 byte 0 10000 Read level sensor SNR level dBM 256 0x0027 2 byte 0 150...

Page 44: ... Read level sensor unit type 0x002E 2 byte 0 m3 s 1 liters 2 ft3 s Read discharge unit type 0x002F 2 bytes 0 maximum peak 1 last peak Peak detector type for level sensor 0x0030 2 bytes 0 65335 Level spectrum amplitude threshold 0x0031 2 bytes Standard deviation Standard deviation of measurement 0x0032 2 bytes 0 360 Level sensor x axis tilt angle 0x0033 2 bytes 0 360 Level sensor y axis tilt angle ...

Page 45: ...filter type 0X000A 2 byte 0 100 Change sensitivity level 0X000C 2 byte 0 3840 Change SNR threshold dBm 256 0x001C 2 byte 0 15000 Velocity min mm s 0x001D 2 byte 0 15000 Velocity max mm s 0x0028 2 byte 0 200 Change number of frames for level sensor window filtering 0x0029 2 byte 0 no filter 1 IIR filter 2 moving average 3 median filter 4 standard deviation Change level sensor filter type 0x002A 2 b...

Page 46: ...mmand Response Details Address Query a CR LF Device will identify using its SDI 12 address default address is 0 Ping Sensor a a CR LF Device will respond if its address is a Address Change aAb b CR LF Device will respond if its address is a with its new address b Send Identification aI a13GEOLUX 2300WLfff CR LF a address SDI 12 version 1 3 vendor identification GEOLUX sensor model 2300W sensor ver...

Page 47: ... LF Concurrent Measurement Send Data aC aCC ammm12 CR LF aD0 a val0 CR LF a val0 CRC CR LF aD1 a val1 CR LF a val1 CRC CR LF aD2 a val2 CR LF a val2 CRC CR LF Additional Data aD3 aD9 a CR LF a CRC CR LF No values are returned for additional data Continuous Measurement aR0 aR9 a CR LF a CRC CR LF The continuous mode is not sup ported Get Velocity Discharge Unit aXGWUN a d CR LF d measurement unit f...

Page 48: ...ctive Zone Value aXGDZ1 a f CR LF f active zone maximum value sensor will not report measure ments higher than this Set Maximum Active Zone Value aXGDZ1 f a f CR LF f active zone maximum value sensor will not report measure ments higher than this Get Sensor Height Value aXGSHR a f CR LF f sensor height above riverbed Set Sensor Height Value aXGSHR f a f CR LF f sensor height above riverbed Set Cur...

Page 49: ...ponds to the maximum radar signal reflection 1 report the last peak which corresponds to the furthest reflection from the radar this may include multipath reflections in typical cases and should be avoided Set Peak Detector Type For Level aXGPDT d a d CR LF d identifies the peak detector type can be any of the following 0 report the distance to the maximum peak which corresponds to the maximum rad...

Page 50: ... select Flow Meter from the window which appears In the next window select the appropriate COM port and interface If RS 485 interface is selected additionally select the baud rate and the Modbus ID In case of multiple devices connected on a single RS 485 bus make sure that each device has a unique Modbus ID When the Connect button is clicked Geolux Instrument Configurator will try to establish a d...

Page 51: ...e 4 20 mA output 4 20 mA min 4 20 mA max Level 4 20 mA min Level 4 20 mA max Processing Sensitivity level SNR threshold Filter length Direction filter Level filter type Level filter length IIR constant Amplitude threshold Peak detector type Measurement Discharge unit Velocity unit Level unit PGA sensitivity Velocity min Velocity max Level active zone min Level active zone max Level sensor hight Po...

Page 52: ...cho Curve tab and clicking the Load echo curve button loads the current echo curve The echo curve plot shows both the incoming and outgoing directions with yellow and blue lines respectively Depending on the Direction filter selected in Settings the echo curve which is not of interest will be shown in grey If desired echo curves can be saved to a csv file Picture 10 Geolux Instrument Configurator ...

Page 53: ...clicking the Clear button clears the previously acquired data Picture 12 Channel Profile Geometry Saved on the Device Navigating to the Profile tab enables the user to define the channel profile geometry and discharge parameters which are used for discharge calculation If the channel profile geometry is already defined and saved to the device the existing configuration will be loaded and the profi...

Page 54: ...d on the device Picture 14 Select a Shape or Define the Channel Profile Geometry Manually 8 1 Configuring the Unit for Discharge Calculation If there is no channel profile geometry saved on the device or if the user has deleted the defined geometry and wants to define a new one the geometry can be manually defined or a predefined shape can be selected to define the channel profile geometry as desc...

Page 55: ...icture 16 Radar Position On the right side of the channel profile geometry definition page in the Radar position section the user has to input the Sensor x offset and Sensor y offset of the radar X offset of the radar is the distance from the leftmost point of the channel to the radar while the y offset represents the distance from the radar to the lowest point of the channel After inputting or ch...

Page 56: ...ometry by adding points the Set or Delete button must be selected after inputting the x and y coordinates of a certain point otherwise the next point cannot be added Picture 18 Import csv File Preview Window If the user has the geometry saved in a csv file a preview window with the values from the csv file will appear as shown in Picture 18 In the preview window the user must select the unit type ...

Page 57: ... k factor values corresponding to different water level values by clicking the Add k factor button After the discharge parameters have been defined the values will be drawn on a graph next to the defined channel profile geometry picture After defining the channel geometry and discharge parameters the changes need to be saved to the device This is done by clicking the Save changes button If the use...

Page 58: ... Defining the Discharge Parameters 8 1 2 Selecting a Predefined Channel Profile Shape After clicking the Select profile shape button Picture 14 or Select shape button Picture 21 a new window appears with 9 predefined shapes from which the user can choose Picture 22 Predefined Shapes ...

Page 59: ...following pictures 20 25 show the definition of 2 different channel shapes Clicking the Next button leads to the next step i e defining the y offset of the radar Picture 24 The required y offset distance is clearly show in the picture as well as the values defined in the previous step If changes need to be made to the values from the previous step it can be done by clicking the Back button Picture...

Page 60: ... WL Non Contact Flow Meter The next step is to define the x offset of the radar Defining the x offset of the radar concludes the channel profile geometry definition Picture 24 Defining the x Offset of the Radar Picture 26 Channel Geometry Defined ...

Page 61: ...he values will appear in green on the graph next to the channel geometry picture as seen in Picture 28 Picture 27 The Defined Shape Shown in the Main Window Picture 28 Defining the Discharge Parameters After completing all the steps of defining the channel geometry the selected shape will appear in the Main window and the Radar position and Channel geometry sections will be defined by the inputted...

Page 62: ...n channel flows Discharge is calculated by multiplying mean flow velocity and channel cross section area The cross section area is the area of the slice in the water column made perpendicular to the flow direction Let us assume a rectangular channel profile with constant flow velocity at all points as seen in Picture 29 Picture 29 Simple Channel Diagram The discharge can be calculated according to...

Page 63: ...rement The mean cross section flow velocity needs to be determined from measured surface flow velocity Studies performed by USGS reveal that typically the mean velocity is 80 95 of the surface velocity the average being 85 Knowing non rectangular area of the stream cross section and knowing the surface flow velocity the following formula can be used Q 0 85 V A More details about water flow measure...

Page 64: ...to brown and white wires of the instrument cable The power supply must be able to deliver at least 500 mA of current 3 Check RS 232 connector The yellow green and grey wires from the instrument cable must be properly connected to the serial port on the computer Make sure that the grey wire signal ground is connected the RS 232 connection will not work if the signal ground is not connected Also mak...

Page 65: ...85 interface 1 Make sure that the cable is properly connected to the instrument Check that the cable M12 circular connector is firmly connected and screwed to the instrument It is not sufficient to simply attach the cable connector to the instru ment connector the cable connector must be screwed into the instrument connec tor 2 Check power supply Make sure that the power is being supplied to the i...

Page 66: ...evice must have a unique slave device ID assigned so that the bus master can distinguish between the devices If two or more devices are assigned the same slave device ID a bus conflict will happen and prohibit the master to correctly communicate with the slave devices To resolve this problem change the instrument s slave device ID to a unique number through the Geolux Instrument Configurator PC ap...

Page 67: ... important that both the data line and the signal ground lines are connected The 4 20 mA output is not correct 1 Make sure that the cable is properly connected to the instrument Check that the cable M12 circular connector is firmly connected and screwed to the instrument It is not sufficient to simply attach the cable connector to the instrument connector the cable connector must be screwed into t...

Page 68: ... and the water surface There should be no obstructions between the instrument and the water surface so that the radar waves can freely travel from the instrument s antenna to the water surface and back Objects such as rocks construction elements metal concrete etc vegetation tree branches water vegetation etc can all affect the instrument s reading If there are some minimal obstructions far away f...

Page 69: ...ional range the instrument will not be able to measure the distance and the water level 4 Check that the distance between the instrument and the water surface is within configured active zone Connect the instrument to the Geolux Instrument Configurator PC application over RS 232 connection Check the active zone parameters if the distance to the actual water surface is outside of the predefined act...

Page 70: ...GLX RSS 2 300 WL User Manual 67 GLX RSS 2 300 WL Non Contact Flow Meter 11 Appendix A Mechanical Assembly ...

Page 71: ...2022 ...

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