Geolux LX-80S Manuel utilisateur
Copyright ©2023 Geolux d.o.o. All rights reserved.
LX-80S
Snow Level Sensor
User Manual
v2.5.5
Starting Point
Thank you for purchasing the Geolux LX-80S snow level sensor! We have put together the
experience of our engineers, the domain knowledge of our customers, the enthusiasm of our team,
and the manufacturing excellence to deliver this product to you.
You may freely rely on our eld-proven radar technology. The use of top-quality components and
advanced signal processing algorithms ensures that the Geolux snow level sensor can be used in
various applications and environments.
We have created this User manual in order to assist you with setting up and using the Geolux
instrument.
Should there be any questions left unanswered, please feel free to contact us directly:
Geolux d.o.o.
Ljudevita Gaja 62
10430 Samobor
Croatia
E-mail: [email protected]
Web: www.geolux.hr
Contents
1. Introduction 1
2. Electrical Characteristics 2
3. Connector Pin-Out 3
3.1. Serial RS-232 Interface 4
3.2. Serial RS-485 Interface 4
3.3. Analog 4 – 20 mA Output 5
3.3.1. Devices With Serial Numbers Not Starting With LX15-4 5
3.3.2. Devices With Serial Numbers Starting With LX15-4 8
3.4. SDI-12 Interface 8
4. Installing the Snow Level Sensor 9
4.1. Rain and Wind 10
4.2. Interference and Multiple Radars 10
4.3. Fogging and Evaporation 10
4.4. Reections 11
4.5. Relative Measurement 11
4.6. Units 12
4.7. Radar Calibration 12
5. Radar Settings 13
6. Data Interface 20
6.1. Serial RS-232 Interface 20
6.2. Serial RS-485 Interface 20
7. Data Protocols 21
7.1. NMEA Protocol (RS-232) 21
7.2. Servicing Protocol (RS-232) 22
7.3. Modbus Protocol (RS-485) 29
7.3.1. Modbus Input Registers 35
7.4. SDI-12 Protocol 37
8. Geolux Instrument Congurator 42
9. Troubleshooting 46
10. Appendix A – Mechanical Assembly 53
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LX-80S Snow Level Sensor
1
Introduction
Geolux LX-80S is the innovative snow level sensor that uses advanced 80 GHz radar technology
to accurately measure the distance from the sensor down to the surface of the snow. The LX-
80S offers superior performance compared to traditional ultrasound devices used for snow depth
measurement.
Installing and maintaining the LX-80S is easy, and the device can cover a long detection distance
of up to 15 meters. The radar technology allows for non-invasive measurement from above the
snow, ensuring that the snow’s structure is not disturbed in any way.
The LX-80S has many applications, including continuous monitoring of snowpack buildup and
melting, making it essential for meteorological monitoring, hydrological planning, avalanche
warning, and ski resorts. The device provides accurate data on snow depth, which is crucial for
many industries, especially those that depend on snow conditions.
Unlike ultrasound devices that require temperature compensation due to their distance
measurement being affected by air density, the LX-80S radar is not impacted by such
environmental changes. Moreover, ultrasonic sensors are more susceptible to negative effects from
snowfall or icicles, which can form close to the device. However, the LX-80S radar uses advanced
signal processing algorithms for precipitation detection, and has a narrow radar beam of only 5°,
which prevent such issues.
The low power consumption of the instrument, small form factor and a rugged enclosure make this
instrument easy to setup and use.
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LX-80S Snow Level Sensor
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Electrical Characteristics
The electrical characteristics of the Geolux LX-80S snow level sensor are given in Table 1.
Table 1. Electrical Characteristics
Parameter MIN TYP MAX Unit
Communication interface:
RS-232 interface speed
RS-485 interface speed
9600
9600
115200
115200
bps
bps
Radar Sensor
Frequency
Beam-width (3dB) – Azimuth
Beam-width (3dB) – Elevation
77.000
5 (±2.5)
5 (±2.5)
81.000 GHz
°
°
Power supply voltage 9.0 12.0 27.0 V
Power
Operational
Standby mode
Sleep mode
360
150
30
600 mW
mW
mW
Operational temperature range -40 +85 °C
Measurement range 0.4 15 m
Accuracy 1 mm
Resolution 0.5 mm
Ingress Protection Rating IP68
Mechanical ф65 x H78 mm
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LX-80S Snow Level Sensor
3
Connector Pin-Out
The snow level sensor uses robust IP68 circular M12 connector with 12 positions and a mating
cable, both delivered standardly with the instrument. The connector and cable details are shown in
Picture 1 while Table 2 gives a detailed description of each pin.
Picture 1. Snow Level Sensor Connectors
Table 2. Connector and Cable Pin-out
Pin No. Wire Color Pin Name Pin Description
1 White GND This pin should be connected to the ground (neg-
ative) pole of the power supply.
2 Brown +Vin This is the pin with the instrument’s power supply.
The snow level sensor power supply voltage must
be between 9 VDC to 27 VDC, and the power sup-
ply must be able to provide at least 0.65 W.
3 Green RS232 – TxD RS-232 data transmit signal.
4 Yellow RS232 – RxD RS-232 data receive signal.
5Grey GND Signal ground.
6 Pink CAN – H CAN2.0B high signal. (optional)
7 Blue CAN – L CAN2.0B low signal. (optional)
8 Red V+ Output power supply (+Vin) for supply of exter-
nal optional equipment and for use with analog
4 – 20 mA output.
4 – 20 mA LOOP+ * Positive connector for 4 – 20 mA output loop.
9 Orange RS485 – D- RS-485 data transmitter/receiver low signal.
10 Dark Red RS485 – D+ RS-485 data transmitter/receiver high signal.
11 Black SDI-12 SDI-12 communication interface.
12 Purple 4 – 20 mA Output Analog 4 – 20 mA output.
4 – 20 mA LOOP- *Negative connector for 4 – 20 mA output loop.
* 4–20 mA LOOP+ and LOOP- is used on devices with serial numbers starting with LX15-4 (e.g. LX15-401234)
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LX-80S Snow Level Sensor
3.1. Serial RS-232 Interface
Serial RS-232 interface is implemented as standard PC full-duplex serial interface with voltage
levels adequate for direct connection to PC computers or other embedded devices used for serial
RS-232 communication.
When the RS-232 interface is connected to a standard DB-9 PC connector, TxD line (green wire)
is connected to pin 2 and RxD (yellow wire) is connected to pin 3. In order for the serial interface
to operate properly, an additional connection of signal GND (grey wire) is needed on pin 5 of the
DB-9 connector. Optionally, Geolux can supply a cable with DB-9 connector connected to the
cable. This requirement must be specied when placing an order.
Several communication protocols are available. Additional custom protocols can be implemented
on request. Detailed description of communication protocols is given in chapter 7 of this user
manual.
Picture 2. Serial RS-232 DB-9 Cable
3.2. Serial RS-485 Interface
Serial RS-485 interface is implemented as standard industrial half-duplex communication
interface. The communication interface is internally short-circuit and overvoltage protected.
Depending on the receiving device, the interface can be used with only two wires (D+ dark red
wire & D- orange wire) while in some cases the ground connection (signal GND grey wire) is also
required. For more details please consult receiver specication.
The most common communication protocol used with RS-485 interface is Modbus-RTU, but other
protocols are also available on request. Detailed description of communication protocols is given in
chapter 7 of this user manual.
Geolux recommends using Waveshare USB TO RS232/485/TTL converter for connecting Geolux
instruments to computers without a native RS-232 port.
https://www.waveshare.com/catalog/product/view/id/3629/s/usb-to-rs232-485-ttl/category/37/
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LX-80S Snow Level Sensor
3.3. Analog 4 – 20 mA Output
Analog current 4 – 20 mA output is provided for easier compatibility with older logging and control
systems. The implementation of the 4 – 20 mA output differs depending on the serial number of
the level meter as explained in the next two chapters.
3.3.1. Devices With Serial Numbers Not Starting
With LX15-4
The output is implemented as current sink architecture with common ground. Maximal voltage
applied to the sink can go up to 30 VDC, providing greater exibility in connection of the sensor to
PLCs, loggers, or data concentrators.
Signal range and function for 4 – 20 mA analog output can be congured in the setup application
so the sensor will be able to signal best suitable value range with available current range. Current
step in the sensor is 0.3 µA, which limits the resolution, so care must be taken while setting the
minimal value to be represented by 4 mA and the maximal value to be represented by 20 mA, so
the resolution is sufcient for the system requirements.
Measurement of the current by the client device (logger, PLC, modem etc.) must be implemented as
the high side current measurement as shown in Picture 4. If a sensing resistor is used, resistance
should be selected from the range of 10 Ω up to 500 Ω, with a recommended value of 100 Ω for
the sensing resistor.
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LX-80S Snow Level Sensor
Picture 4. High Side Current Measurement for the 4 – 20 mA Analog Output
Connection to Schneider TM3AM6 analog input module
The TM3AM6 analog module contains 4 analog inputs, marked I0 to I3. Each analog input consists
of two connectors, marked as I+ and I-. Each analog input can be congured to work either as
analog voltage input (0 – 10 V or -10 to +10 V), or as analog current input (0 – 20 mA or 4 – 20
mA). This is the wiring diagram from the TM3AM6 user manual:
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LX-80S Snow Level Sensor
In order to connect the Geolux instrument to the TM3AM6 module, the rst step is to congure the
selected input port as analog current input operating on 4 – 20 mA range. This is done by using
Schneider software. After the analog input module is congured, the second step is to connect the
Geolux instrument to the TM3AM6 module, according to the following schematic diagram:
It is important to note that the 4 – 20 mA wire from the Geolux instrument should be connected to
negative (-), not positive (+) terminal of the analog input port.
Table des matières
