Mounting the sensor ................12 Optional Campbell Scientific Mount ..........15 8. Sensor internal connectors’ description ....17 Sensor recommended wiring using Campbell Scientific cables (this cable is supplied already connected as standard) ......19 9. HygroVUE 5, HygroVUE 10 or CS215 T/RH Sensor (CS125 only) ..........
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Table of Contents 11. Message Formats: A breakdown of the different default outputs of the sensor – Basic/Partial/ Full ................24 11.1 Visibility only messages..............25 11.2 Messages with SYNOP Present Weather Codes (CS125 only) ..26 11.3 Messages with METAR Present Weather Codes (CS125 only) ..27 11.4 Messages with Generic SYNOP Present Weather Codes (CS125 only) ....................
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Table of Contents A. CS120A/CS125 block diagram ......A-1 B. Example C code of the CRC-16 checksum ..B-1 C. Present Weather Codes ........C-1 SYNOP Codes produced by the CS125 ........... C-1 METAR Codes produced by the CS125 .......... C-2 NWS Codes produced by the CS125 ..........
Present Weather Sensors Introduction The CS120A is a visibility sensor. The CS125 additionally detects and reports present weather in the form of SYNOP, METAR or NWS codes. The CS125 has the same specification for visibility measurement as the CS120A. It is possible to upgrade a CS120A to a CS125, please contact Campbell Scientific for more details.
CS120A and CS125 Visibility and Present Weather Sensors General safety This manual provides important safety considerations for the installation, operation and maintenance of the sensor. These safety considerations are classified into three levels: WARNING Warnings alert the installer or user to serious hazards.
Figure 1-1. Particles in the sample volume scatter light in all directions, including into the detector The CS120A and CS125 comprise an emitter and detector aligned as in Figure 1-1. The emitter produces a beam of near infra-red light pulsed at 1 kHz.
CS120A and CS125 Visibility and Present Weather Sensors Figure 1-2. Signals from large, slow falling snowflakes and smaller, faster, raindrops The CS125 also has a temperature sensor. These three parameters, fall speed, size and temperature are used to identify the type of particle. If an additional external temperature and relative humidity probe is connected then a wet-bulb temperature can be calculated.
CS125, at 1 minute intervals (see Section 11, Message Formats: A breakdown of the different default outputs of the sensor – Basic/Partial/Full (p. 24) To start using the CS120A or CS125, first connect a DC supply matching the specification in Section 3.1, Electrical specification , to the red and black (p.
CS120A and CS125 Visibility and Present Weather Sensors 0’ will access the menu structure, see Section 15, Entering the sensor menu system (p. 49) Measurement specification Minimum Nominal Maximum Value Value Value Visibility characteristics Reported visibility (metric) 5 metres 75,000...
CS120A and CS125 Visibility and Present Weather Sensors Hood heater power supply Hood heater voltage (AC or DC) Hood heater wattage (at 24V AC or User alarm outputs User output high level (at 85ºC) 3.8V User output high level (at 25ºC ) 4.13V...
Hood heater Turn Off >25°C Extended temperature ranges are only guaranteed if the sensor has been tested by Campbell Scientific and verified within this temperature range. Some degradation of absolute accuracy can be expected at the extremes of the extended ranges.
CS120A and CS125 Visibility and Present Weather Sensors Weights Sensor weight: 3 Kg Shipping weight: 6 Kg (including packing box) Mounting Sensor mounting: Bracket mounts on a vertical pole 32-52.5 mm diameter. The mounting bracket has cut-outs for band clamps for larger diameter masts.
CS120A and CS125 Visibility and Present Weather Sensors Figure 7-1. Airflow In order to reduce the service frequency with the unit, the sensor should be placed away from sources of contamination, in the case of roadside monitoring; larger mounting poles can be used. More regular maintenance will be required when the instrument is placed in areas where contamination is unavoidable or where measurements may be safety critical.
CS120A and CS125 Visibility and Present Weather Sensors Figure 7-2. Grounding boss Mounting the sensor A quick release pole mounting kit is supplied with the sensor. If a power supply enclosure has been supplied with the sensor it can be mounted on the pole, near its base using the brackets supplied with the enclosure.
CS120A and CS125 Visibility and Present Weather Sensors CAUTION Do not remove the mounting plate as this will compromise resistance to water ingress. Figure 7-3. Mounting arrangement If you need to mount the sensor to a flat surface, remove the plastic formers from the mounting brackets and use the holes as shown in Figure 7-4.
CS120A and CS125 Visibility and Present Weather Sensors Figure 7-4. Mounting to a flat surface Slots are provided to allow band clamps to be used with larger diameter masts, see Figure 7-5. Figure 7-5. Use of band clamps...
CS120A and CS125 Visibility and Present Weather Sensors Optional Campbell Scientific Mount A Campbell Scientific ‘optical sensor mount’ is available. This will put the sample volume at about 1.5 m in compliance with the WMO ‘Guide to Meteorological Instruments and Methods of Observation’, 7 Edition, Section 9.3.4.
CS120A and CS125 Visibility and Present Weather Sensors If applicable, use the following installation instructions. Install the mount on a concrete foundation. If one does not already exist then a concrete foundation should be constructed at least 600 mm square and 600 mm deep.
CAUTION 10 m is the longest length of the cable type supplied recommended. particular, additional RS-485 communication should be twisted pair. Please contact Campbell Scientific if you wish to use a longer length of cable.
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CS120A and CS125 Visibility and Present Weather Sensors Figure 8-1. Connections Connector A - Five way connector Pin number Description Notes Pin 1 +ve supply Main electronics +ve supply input Pin 2 Auxiliary Electronics 0V. Common with the main electronics 0V.
Two types of configuration cable are available from Campbell Scientific that plug directly into connector B in place of the normal connector and cable. One has a RS-232 or RS-485 output according to how the CS120A/CS125 is configured (Figure 8-4) and one has a USB output (Figure 8-5).
CS120A and CS125 Visibility and Present Weather Sensors Figure 8-4. Configuration cable Figure 8-5. USB configuration cable HygroVUE 5, HygroVUE 10 or CS215 T/RH Sensor (CS125 only) The CS125 has a temperature sensor mounted in the crossarm that is used in determining precipitation type.
CS120A and CS125 Visibility and Present Weather Sensors WMO – No. 8, 2.1.4.1 recommends temperature measurement at a height of between 1.2 and 2.0 m above ground. The screen should be below the height of the CS125 electronics box. Connections for temperature and RH sensor HYGROVUE 5 &...
CS120A and CS125 Visibility and Present Weather Sensors 10. Functions of the internal switches The sensor is equipped with four switches located within the main enclosure. These switches perform certain functions at power up; their functions are detailed in Table 10-1.
, on how to set default outputs). The SYNOP Full Format message is the (p. 49) default message for the CS125 and the Full Format Visibility only message is the default for the CS120A. These can be selected from the Message – Sub 3 menu. CS125 MESSAGE - SUB 3 Set the message output format.
CS120A and CS125 Visibility and Present Weather Sensors NOTE STX and ETX are hexadecimal command characters. NOTE Refer to Appendix B, Example C code of the CRC-16 checksum , for the checksum algorithm. (p. B-1) 11.1 Visibility only messages Basic Format, Visibility Only...
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CS120A and CS125 Visibility and Present Weather Sensors Table 11-1. Summary of message IDs and descriptions Message ID break down Definition Basic format. Contains only distance and system information Partial format. Contains user alarm outputs Full format. Contains all system alarms codes...
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CS120A and CS125 Visibility and Present Weather Sensors NOTE In accordance with WMO requirements the sensor produces visibility measurement that are either one or ten minute rolling averages that are updated at the chosen output interval or when the sensor is polled. Those averages are not direct averages of MOR measurements but are averages of extinction coefficient and that average is then used to calculate the MOR for that period.
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CS120A and CS125 Visibility and Present Weather Sensors System alarms break down Alarm Range Severity Definition Hood 0 = Temperature is within operating conditions temperature 1 = Too low. Less than -40°C 2 = Too high. Over 80°C 3 = No sensor detected or below -56°C...
CS120A and CS125 Visibility and Present Weather Sensors SYNOP code* Range Definition See Appendix SYNOP weather code for the last minute as defined by the WMO code table 4680. (-1 indicates either an error or that the sensor has been powered up less than one...
= 11 - Custom output = 12 -> The custom message format allows the CS120A/CS125 message to be modified to meet particular requirements. The custom message contains a fixed basic set of variables and up to 16 additional fields. NOTE The custom message output is only available on OS7 and above.
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CS120A and CS125 Visibility and Present Weather Sensors Menu 1: The message output menu CS125 MESSAGE - MENU 1 ID 0 S/N 1006 (1) Set message format:FULL SYNOP (2) Toggle units:METRES (3) Toggle polled or continuous mode:CONTINUOUS (4) Set continuous mode message-interval:60 second(s)
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CS120A and CS125 Visibility and Present Weather Sensors CS125 MESSAGE - SUB 4 Configure the message output format: 1 - Averaging duration 2 - User alarms 3 - System alarms 4 - Dirty windows values 5 - Sensor serial number...
All three of these methods use the sensor’s serial connector B to communicate with the sensor. This can be via the normal communications cable or a configuration cable as described in Section 8.1, Sensor recommended wiring using Campbell Scientific cables (this cable is supplied already connected as standard) (p. 19) 12.1 Configuring a PC for talking to the sensor...
CS120A and CS125 Visibility and Present Weather Sensors The following settings should then be used by default: Bits per second: 38400 Data bits: 8 Parity: none Stop bits: 1 Flow control: none Ensure that if the baud rate of the unit has been adjusted and then the corresponding bits per second value is entered in the port settings of the terminal emulator.
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CS120A and CS125 Visibility and Present Weather Sensors Table 13-1. User definable settings and descriptions Name Range Description Factory default Baud rate Baud rate for the main RS-232/RS-485 interface 0 = 115200 bps 1 = 57600 bps 2 = 38400 bps...
CS120A and CS125 Visibility and Present Weather Sensors Table 13-1. User definable settings and descriptions Name Range Description Factory default Hood heater override 0 = Allow the sensor to automatically control the hood heaters 1 = Turn the hood heaters off...
CS120A and CS125 Visibility and Present Weather Sensors Section 14.2, Introduction , if a setting is going to be changed on a regular (p. 1) basis e.g. heater controls. See Section 12, Interface methods – Device Configuration Utility/Command line/Menu , for more information on the values used by the ‘SET’...
CS120A and CS125 Visibility and Present Weather Sensors 14.2 The SETNC Command The format of the SETNC command is nearly exactly the same as the SET command. The only functional difference is that the SETNC command does not commit the values set into flash memory. This means that the next time the sensor is power cycled it will revert back to its previous settings.
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CS120A and CS125 Visibility and Present Weather Sensors These selections output more than one variable (1) These options will only be available if you’re using a CS125 (2) Only outputs a valid final message value when a CS215 temperature and humidity probe is connected...
CS120A and CS125 Visibility and Present Weather Sensors 0010 Sensor serial number 0008 Dirty windows values 0004 System alarms 0002 User alarms 0001 Averaging duration 121C Sum for MSGSET message The hex value is the hexadecimal sum of the hex values of the chosen fields (in bold text).
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CS120A and CS125 Visibility and Present Weather Sensors Example of a GET command GET:0:0:XXXX: Data returned by the GET command GET returned data Example Description 0x02 Sensor ID User Alarm 1 Set User Alarm 1 Active (0 = less than)
CS120A and CS125 Visibility and Present Weather Sensors User Alarm 2 not set User Alarm 2 not active User Alarm 2 distance = 10000 metres Serial baud rate 2 (= 38400 Bd) Serial number = 1009 Visibility Units = M...
CS120A and CS125 Visibility and Present Weather Sensors Example of the MSGGET command as sent to the sensor The message sent is: MSGGET:0:0:C6ED: The response is: 161C 7067 14.6 The POLL command – Polling the sensor The POLL command requests the current visibility and/or alarm conditions from the sensor.
CS120A and CS125 Visibility and Present Weather Sensors POLL:2:0:545B: POLL:3:0:636B: POLL:4:0:E6FB: POLL:5:0:D1CB: POLL:6:0:889B: POLL:7:0:BFAB: POLL:8:0:939A: POLL:9:0:A4AA: 14.7 The ACCRES command – Resetting the accumulation value If accumulation is included in a custom message the ACCRES command resets the accumulation to zero. See Section 11.6, Custom message format (p.
CS120A and CS125 Visibility and Present Weather Sensors Example of an ACCRES command ACCRES:2:0:3A68: If the setting to check the checksum on received commands is enabled the checksum varies with the Sensor ID value. 15. Entering the sensor menu system The user can enter the menu system by typing ‘open id’...
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Section 11, Message Formats: A breakdown of the different default outputs of the sensor – Basic/Partial/Full (p. 24) Note that the CS120A Visibility Sensor can only output messages 0-2 and a limited custom message. CS125 MESSAGE - SUB 3 Set the message output format.
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CS120A and CS125 Visibility and Present Weather Sensors While in the message output menu, typing ‘2’ will toggle the units through the options ‘METRES’ and ‘FEET’ or by typing ‘4’ it will allow the message interval to be entered. In setup menu, typing ‘2’ allows the User Alarms to be set, again by toggling through options or changing values.
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CS120A and CS125 Visibility and Present Weather Sensors NOTE Once a calibration is finished changes are immediate, but factory calibrations can be restored if needed using Option ‘(2)’ in the calibration menu. The disk constants however remain as the last disk used.
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If there is a flash error or signature error it is recommended that you contact Campbell Scientific. The sensor power down voltage shown before the supply voltage is not available for CS120A sensors with serial numbers less than E1030. Menu 5: The communication menu CS125 COMMUNICATIONS - MENU 5...
CS120A and CS125 Visibility and Present Weather Sensors down voltage to be set. If set this will put the sensor into a low power state (which will not make measurements) before the battery voltage has fallen low enough to damage a back-up battery. The RH threshold for a CS125 can also be set from this menu.
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CS120A and CS125 Visibility and Present Weather Sensors Once you have selected menu item 3 you should be presented with the following screen. CS125 CALIBRATION - MENU 3 ID 0 S/N 1006 (1) Perform calibration (2) Restore the factory calibration...
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CS120A and CS125 Visibility and Present Weather Sensors CS120A/CS125 High grade calibrator serial number, extinction coefficient (EXCO) and equivalent MOR will be written here Figure 16-1. Calibration disk When you have entered the calibrator information the sensor will wait for you to place the foam bungs into the sensor hoods.
CS120A and CS125 Visibility and Present Weather Sensors Figure 16-2. Mounting calibration disk Starting light level calibration. This test will take approximately two minutes. This part of the test will take approximately two minutes. Every ten seconds a dot should appear indicating that the test is progressing as normal.
CS120A and CS125 Visibility and Present Weather Sensors This should be carried out every two years to check for any slight drift in the dirty window detection. To carry out the dirty window zero offset calibration make sure the windows are very clean.
CS120A and CS125 Visibility and Present Weather Sensors 17. Performing an operating system update Operating system updates for the present weather sensor are performed using Campbell Scientific’s Device Configuration Utility (DevConfig) software. Please refer to the help built into the DevConfig software for full instructions on how to update the sensor operating system.
The sensor is a robust instrument that will provide years of uninterrupted weather monitoring. Calibration is carried out at the factory and can be redone easily on site with the optional sensor calibrator or carried out by Campbell Scientific if required. Only general cleaning of the lenses is required to keep the sensor working efficiently.
CS120A and CS125 Visibility and Present Weather Sensors CAUTION If the lenses require cleaning, it is very important that only a proper lens cloth or lens tissue be used. The use of inappropriate materials to clean the lenses can permanently damage or reduce the effectiveness of the lenses leading to errors in measurement of precipitation and visibility.
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CS120A and CS125 Visibility and Present Weather Sensors next metal tray above the bags. If placed in a radiating exposed infra-red element type oven, shield the bags from direct exposure to the heating element, giving the closest bags a minimum of 40 cm clearance from the heat shield.
Operation of the CS125 with either the WXT531, or WXT535, requires the CS125 to be installed with Operating System 11 (OS11) or later. Free OS upgrades for CS125 sensors are available from Campbell Scientific. Note on connecting a hail sensor to a...
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Addendum – Hail monitoring (CS125 only) Figure 1. Electrical connections between the WXT531 (shown) or WXT535 Hail Sensor and host CS125...
Appendix B. Example C code of the CRC-16 checksum This appendix is for programmers implementing their own code to communicate with the sensor. The Checksum command in CRBasic can generate a CRC-16 checksum. Command: Checksum/ChkSumString,1,0). The checksum includes all characters excluding the SOT, EOT and the checksum itself.
Appendix C. Present Weather Codes C.1 SYNOP Codes produced by the CS125 56 codes are available. Weather Type 4680 Code No significant weather observed Haze or smoke, or dust in suspension in the air, visibility ≥ 1 km* Haze or smoke, or dust in suspension in the air, visibility < 1 km* Mist Fog (in the preceding hour) Precipitation (in the preceding hour)
Intensity qualifiers, ‘-‘ for light, ‘+’ for heavy, may be added in front of DZ, RA, SN, and PL Combinations, for example RASN for rain and snow can be reported. *Only reported if an optional hail sensor is connected. Contact Campbell Scientific for details. C.3 NWS Codes produced by the CS125...
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Appendix C. Present Weather Codes Z (freezing) may be added as a descriptor in front of L and R Intensity qualifiers, ‘-‘ for light, ‘+’ for heavy, may be added after the NWS code.
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See Product Details on the Ordering Information pages at www.campbellsci.com. Other manufacturer's products, that are resold by Campbell Scientific, are warranted only to the limits extended by the original manufacturer. Refer to www.campbellsci.com/terms#warranty...
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Decontamination” form and comply with the requirements specified in it. The form is available from your CAMPBELL SCIENTIFIC regional office. Campbell Scientific is unable to process any returns until we receive this statement. If the statement is not received within three days of product receipt or is incomplete, the product will be returned to the customer at the customer’s...
Dispose of spent batteries properly. WHILE EVERY ATTEMPT IS MADE TO EMBODY THE HIGHEST DEGREE OF SAFETY IN ALL CAMPBELL SCIENTIFIC PRODUCTS, THE CUSTOMER ASSUMES ALL RISK FROM ANY INJURY RESULTING FROM IMPROPER INSTALLATION, USE, OR MAINTENANCE OF TRIPODS, TOWERS, OR ATTACHMENTS TO TRIPODS AND TOWERS SUCH AS SENSORS, CROSSARMS, ENCLOSURES, ANTENNAS, ETC.
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Campbell Scientific regional offices Australia France Thailand Location: Garbutt, QLD Australia Location: Vincennes, France Location: Bangkok, Thailand Phone: 61.7.4401.7700 Phone: 0033.0.1.56.45.15.20 Phone: 66.2.719.3399 Email: info@campbellsci.com.au Email: info@campbellsci.fr Email: info@campbellsci.asia Website: www.campbellsci.com.au Website: www.campbellsci.fr Website: www.campbellsci.asia Brazil Germany Location: São Paulo, SP Brazil...
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