Gill GMX100 User manual

User Manual
For Compact Weather Stations
Document Number: 1957-PS-021 Issue 3 applies to units with firmware 2669 V2.XX.XX and
Serial Numbers 1801XXXX onwards.
Gill Instruments Limited
SaltmarshPark, 67 Gosport Street, Lymington,
Hampshire, SO41 9EG, UK
Tel:[phone], Fax: [phone]
Email: [e-mail] Website: www.gillinstruments.com
GM240
GMX541
GMX550
GMX600
GMX551
GMX531
GMX500
GMX300
GMX200
GMX100
GMX301
GMX400
GMX501
GMX101

Gill Instruments Ltd
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MaxiMet Page 2 Issue 3
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Contents
1. FOREWORD ...............................................................................................................6
2. INTRODUCTION..........................................................................................................6
2.1. MaxiMet Part Numbers and Parameters........................................................... 6
2.1.1 MaxiMet Order Part Numbers (2669 V2.XX.XX Firmware) .......................6
2.1.2 Summary of MaxiMet Sensors and Derived Parameters...........................7
2.1.3 Wind Speed and Direction Sensor (GMX200, GMX240, GMX500, GMX501,
GMX531, GMX541, GMX550, GMX551 and GMX600).................................................8
2.1.4 Solar Radiation Shield (GMX300, GMX301, GMX400, GMX500, GMX501,
GMX531, GMX541, GMX550, GMX551 and GMX600).................................................8
2.1.5 Barometric Pressure (GMX300, GMX301, GMX400, GMX500, GMX501,
GMX531, GMX541, GMX550, GMX551 and GMX600).................................................9
2.1.6 Temperature, Relative Humidity and Dewpoint (GMX300, GMX301,
GMX400, GMX500, GMX501, GMX531, GMX541, GMX550, GMX551 and GMX600)..9
2.1.7 Rain (GMX100, GMX240, GMX400, GMX541, GMX600 (and Gill Spare Part
1957-PK-073)) .............................................................................................................9
2.1.8 Rain (GMX531)........................................................................................9
2.1.9 Rain (GMX550 and GMX551)..................................................................9
2.1.10 Compass (GMX200, GMX240, GMX500, GMX501, GMX531, GMX541,
GMX550, GMX551 and GMX600)..............................................................................10
2.1.11 Compass Declination.............................................................................10
2.1.12 Solar (GMX101, GMX301, GMX501, GMX531, GMX541 and GMX551).10
2.1.13 GPS Option (GMX200, GMX240, GMX500, GMX531, GMX541, GMX550,
GMX551 and GMX600)..............................................................................................10
2.1.14 Inclinometer (All MaxiMet Models, diagram illustrates a GMX550)..........11
3. TECHNICAL SPECIFICATION..................................................................................12
4. PRE-INSTALLATION ................................................................................................17
4.1. Equipment supplied........................................................................................ 17
4.1.2 Optional Extras/Spares:.........................................................................17
4.2. Connector and Cable Assembly...................................................................... 17
4.3. Cabling ...........................................................................................................20
4.3.1 Cable Type............................................................................................20
4.3.2 Cable Length.........................................................................................20
4.4. Connections.................................................................................................... 21
4.4.1 View of the MaxiMet Connector looking down at the Cable Side.............21
4.4.2 9-Way Connector and Cable Connections..............................................21
4.5. Power supplies............................................................................................... 22
4.5.1 MaxiMet Units........................................................................................22
4.6. Connecting to a PC using RS232 (default setting)..........................................22
4.7. Connecting to a PC using RS422 (Not a default setting).................................23
4.8. Using RS485 (not a default setting)................................................................ 23
4.9. Using SDI-12 (2 wire network, not a default setting)........................................24

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4.10. Using the MaxiMet GMX531 with a Supplied Kalyx Rain Gauge or
GMX550/GMX551 (user supplies a Rain Gauge) .......................................................24
4.11. Using the MaxiMet GMX541 with supplied Gill Solid State Rain Gauge.......... 26
4.12. Set-Up Requirements .....................................................................................27
4.12.1 Host System..........................................................................................27
4.12.2 Software................................................................................................27
4.12.3 Bench System Test................................................................................27
4.13. Packaging.......................................................................................................27
5. INSTALLATION.........................................................................................................28
5.1. General Installation Guidelines.......................................................................28
5.1.1 Interference...........................................................................................28
5.1.2 Wind......................................................................................................28
5.1.3 Compass...............................................................................................29
5.1.4 GPS......................................................................................................29
5.1.5 Solar......................................................................................................29
5.1.6 Tilt.........................................................................................................29
5.1.7 Rain ......................................................................................................30
5.1.8 General Alignment.................................................................................32
5.1.9 Mounting Tube e.g. Gill Part 1405-30-056..............................................32
5.1.10 Mounting Bracket e.g. Gill Part 1771-PK-115.........................................33
5.1.11 Dimensions (in mm)...............................................................................34
6. CONFIGURING WITH METSET.................................................................................38
6.1. MaxiMet Default Configurations...................................................................... 38
6.2. Configuring MaxiMet with MetSet....................................................................55
6.2.1 Opening MetSet.....................................................................................55
6.2.2 MetSet Editing Screen...........................................................................57
6.2.3 MetSet Online Settings..........................................................................58
6.2.4 MetSet Editing Pages............................................................................58
6.3. Polled Mode.................................................................................................... 69
6.3.1 Configuration for Polled Mode (MaxiMet Set for Power Mode 0).............69
6.3.2 Data Retrieval in Polled Mode (MaxiMet Set for Power Mode 0).............69
6.4. Configuring MaxiMet for SDI-12...................................................................... 70
6.4.1 SDI-12 Units of Measure........................................................................70
6.4.2 SDI-12 Commands................................................................................71
6.4.3 SDI-12 Commands with CRC ................................................................73
6.5. Configuring MaxiMet for Modbus....................................................................76
6.5.1 MaxiMet Supported Modbus Specification..............................................76
6.6. Configuring MaxiMet for NMEA 0183 Output..................................................88
6.6.1 GMX100 NMEA Output String................................................................88
6.6.2 GMX101 NMEA Output String................................................................89
6.6.3 GMX200 NMEA Output String................................................................90
6.6.4 GMX240 NMEA Output String................................................................91
6.6.5 GMX300 NMEA Output String................................................................93

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6.6.6 GMX301 NMEA Output String................................................................94
6.6.7 GMX400 NMEA Output String................................................................95
6.6.8 GMX500 NMEA Output String................................................................96
6.6.9 GMX501 NMEA output String................................................................98
6.6.10 GMX531, GMX541 and GMX551 NMEA Output String ........................101
6.6.11 GMX550 and GMX600 NMEA Output String........................................103
6.7. Safe Mode.................................................................................................... 106
6.7.1 Summary.............................................................................................106
6.7.2 Safe Mode Method 1...........................................................................106
6.7.3 Safe Mode Method 2...........................................................................109
6.8. Using a Terminal Program to run MaxiMet Check Tilt Function..................... 110
6.9. Using a Terminal Program to Set MaxiMet Date and Time ........................... 111
7. VIEWING MAXIMET DATA STRING .......................................................................112
7.1. Use MetSet to View the MaxiMet Data String ............................................... 112
7.2. Using Gill MetView Software to View the MaxiMet Data String ..................... 113
7.2.1 Opening MetView.....................................................................................113
7.2.2 Scanning for Devices................................................................................114
7.2.3 The MetView Console...............................................................................115
7.2.4 MetView Console Display Options............................................................116
7.2.5 MetView Gauge Ranges and Graphs........................................................117
7.2.6 Data Logging............................................................................................119
7.3. Use a Terminal Program to View the MaxiMet Data String ........................... 120
8. MAINTENANCE & FAULT-FINDING.......................................................................123
8.1. Cleaning and Handling.................................................................................. 123
8.2. Servicing....................................................................................................... 123
8.2.1 Precipitation Sensor.............................................................................123
8.2.2 Solar Sensor........................................................................................126
8.2.3 Compass/GPS Modules.......................................................................126
8.2.4 Wind Sensor (WindSonic)....................................................................126
8.2.5 Barometer ...........................................................................................126
8.2.6 UV Shield (MetSpec)...........................................................................126
8.2.7 Temperature, Humidity and Dewpoint..................................................127
8.2.8 GMX531/GMX541/GMX550/GMX551 Side Connector.........................127
8.2.9 Calibration...........................................................................................127
8.3. Fault-finding.................................................................................................. 127
8.4. Safe Mode.................................................................................................... 128
8.5. Bench Test ................................................................................................... 128
8.6. Returning Units............................................................................................. 129
8.7. Guarantee..................................................................................................... 129
9. APPENDICES..........................................................................................................130
9.1. MaxiMet Output Parameters selectable using MetSet Software.................... 130

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9.2. Glossary & Abbreviations.............................................................................. 143
9.3. Electrical Conformity..................................................................................... 144

Gill Instruments Ltd
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1. FOREWORD
Thank you for purchasing the MaxiMet manufactured by Gill Instruments Ltd.
To achieve optimum performance we recommend that youread the whole of this manual before
proceeding with use.
Gill products are in continuous development and therefore specificationsmay be subject to change and
design improvements without prior notice.
The information contained in this manual remains the property of Gill Instruments andmust not be copied
or reproduced for commercial gain.
2. INTRODUCTION
The Gill MaxiMet sensor units are very robust with no moving parts. The sensor units, output rate and
formats are all user selectable.
The MaxiMet can be used in conjunction with a PC, data logger or other device.
The MaxiMet combines all the instrument data into a single data string. This may be configured for digital
ASCII RS232/RS422/RS485 (2 wire point to point only),digital Modbus RTU/ASCII, NMEA andSDI-12
outputs.
2.1. MaxiMet Part Numbers and Parameters
2.1.1 MaxiMet Order Part Numbers (2669 V2.XX.XX Firmware)
NOTE: For information within the part structure:-
1957-XXX-XX-XXX X– A number greater than 0identifiesthe unit to havea Solar Sensor fitted.
1957-05X-XX-XXX X - A number greater than 0 identifies the unit to have an external rain gauge input.
PROJECTCODE
1957 - 0 X X X - X X - X X X
MaxiMet GPS TBA TBA
0 1 0 0 6 0 0=NoGPS 0 0
0 1 0 1 1=GPS
0 2 0 0
0 2 4 0
0 3 0 0
0 3 0 1
0 4 0 0
0 5 0 0
0 5 0 1
0 5 3 1
0 5 4 1
0 5 5 0
0 5 5 1
0 6 0 0
OPTIONSMODELNUMBER WIND SPEED
Range m/s
GMX Model Number

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2.1.2 Summary of MaxiMet Sensors and Derived Parameters
(See Appendices, Para 9.1 for more details).
GMX Sensor Parameter 100 101 300 301 400 200 240 500 501 531 541 550 551 600
Wind Speed, Relative
Wind Direction, Relative
Compass, Heading
Temperature, Air
Humidity, Relative
Barometric Pressure
Rain/Precipitation (External Gauge)
Solar Radiation
GPS (option) Opt Opt Opt Opt Opt Opt Opt Opt Opt
GMX Derived Parameter 100 101 300 301 400 200 240 500 501 531 541 550 551 600
Average Speed (WMO)
Average Direction (WMO)
Average Corrected Direction
(WMO)
Corrected Direction
Gust Direction (WMO)
Gust Speed (WMO)
Status (Sensors)
Wind Status
Dewpoint
Absolute Humidity
Pressure at Sea Level
Pressure at Station
Precipitation Intensity
Precipitation Total
Precipitation Status
Wind Chill
Heat Index
Air Density
Wet Bulb Temperature
Solar (sunshine) Hours
Twilight
Sunrise
Solar Noon
Sunset
Position of the Sun
Angle of Tilt
Node Letter
Volts (Supply)
Time (and Date)
Corrected Speed GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
Average Corrected Speed (WMO) GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
Corrected Gust Speed GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
Corrected Gust Direction GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
GPS Location (Longitude/latitude) GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
GPS Heading GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
GPS Speed GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt
GPS Status GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt GPS Opt
GPS Opt GPS Opt

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2.1.3 Wind Speed and Direction Sensor (GMX200, GMX240, GMX500, GMX501,
GMX531, GMX541, GMX550, GMX551 and GMX600)
The MaxiMet uses theGill WindSonicwind speed and direction sensor. The WindSonicmeasures the times
taken foran ultrasonic pulse ofsound totravel from the north (N) transducer to the south (S)transducer,
and compares it with the time for a pulse to travel from S to N transducer. Likewise times are compared
between west (W) and east (E), andE and W transducer.
If, for example, a north wind is blowing, then the time taken for the pulse to travel from N to S will be
faster than from Sto N,whereasthe W toE and Eto W times will be the same. Thewind speed and
direction can then be calculated from the differences in the times of flight on each axis. This calculation is
independentof factors suchas temperature.
MaxiMet can output the following wind readings dependingon use ofa Compassor GPS:
Relative wind – wind speed and/or direction, uncorrected, but relative to the north marker, which
may not be facing north.
Correctedwind – with the aid of the CompassMagnetic North corrected wind directioncan be
output.
True wind – wind speed and/or direction information corrected by GPS for any direction
misalignment of the north marker and/or for any motion of the station. (E.g. vehicle or vessel).
2.1.4 Solar Radiation Shield (GMX300, GMX301, GMX400, GMX500, GMX501,
GMX531, GMX541, GMX550, GMX551 and GMX600)
A MetSpec Multi-Plate Solar Radiation Shield is used. The special shield plate
geometry, with its double louvre design, provides excellent response time
performance of quick ambient temperature changes while still working effectively
as a baffle tostop largercontaminants such as salt or dirt from reaching the
temperature and humidity sensor. The shield benefits from very robust material
choice and extremely high UV protection requiring no maintenance.
Compass points
:
The
compass point and
polarity of U andV if the
wind components along
the U and V axis are
blowing in the direction
of the respective arrows.

Gill Instruments Ltd
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2.1.5 Barometric Pressure (GMX300, GMX301, GMX400, GMX500, GMX501, GMX531,
GMX541, GMX550, GMX551 and GMX600)
Barometric pressure is provided by a solid-state device fitted onto a board inside a MaxiMet moulding.
2.1.6 Temperature, Relative Humidity and Dewpoint (GMX300, GMX301, GMX400,
GMX500, GMX501, GMX531, GMX541, GMX550, GMX551 and GMX600)
There is internal solid state sensor circuitry contained within the radiation shield that provides digital
output signals for Relative Humidity, Temperature and calculated Dewpoint.
2.1.7 Rain (GMX100, GMX240, GMX400, GMX541, GMX600 (and Gill Spare Part 1957-
PK-073))
Rain drop detection and a reading of Rain level is provided by using an optical infra-red beam sensor.Infra-
red beams bounce off the inner optical surface between transmitters and receivers. Depending on rain
drop levels the intensity of the beams change and internal digital signal processing allows a measurement
of Rainlevels to bemade. The sensor increments rain detected indefault 0.080mm stepsbut tip size can
be changed. The GMX541 rain gauge is supplied with a 20M lead with 9 way and 4 way connectors fitted.
NOTE: The Optical Sensor provides a General Indication only of rainfall levels for use in situationswhere
low maintenance is required. Use a tipping bucket or equivalent with a MaxiMet (e.g. GMX531, GMX550-
and GMX551) where reference quality precipitation measurements are required.
2.1.8 Rain (GMX531)
A reading of Rain levels is provided by a supplied remote Kalyx traditional tipping bucket rain gauge. A
switch contact closure provides a connection to the GMX531 through a plug-in connector where a tip
occurs for 0.200mm of rainfall. For rainfall rates above 120mm/hour andup to 1000mm/hour then
contact EML in the UK for a mathematical correction to readings.
The Kalyx raingauge is supplied wired toa 20metre longcable which has a 4-wayconnectorfitted toit
that plugsinto a socketin themoulding of theGMX531.
2.1.9 Rain (GMX550 and GMX551)
A Rain Gauge switch contact closure is required to be connected through the 4 way plug-in connector, to
register that a tip has occurred. The default tip size is 0.000mm but this can be adjusted by the user to suit
their supplier rain gauge.

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2.1.10 Compass (GMX200, GMX240, GMX500, GMX501, GMX531, GMX541, GMX550,
GMX551 and GMX600)
MaxiMet contains a 2-axis flux gate compass.
MaxiMet uses the internal compass to electronically sense the horizontal component of the Earths’
magnetic field. Wind direction data is corrected for the orientation of the sensor. The output of the wind
direction is relative to magnetic North.The MaxiMet compass is calibrated at Gill Instruments before the
unit is delivered.
Prior toinstalling MaxiMet itis suggested that for best accuracy a declinationfigure should be entered.
Use of the Compass-Corrected Wind Direction readings allows the unit to be installed such that accurate
positioning of the MaxiMet north marker is not required.
Caution: Gill provide a derived parameter for corrected wind direction and speed information, this derived
parameter is based on an algorithm devised by Gill and may not satisfy or meet other known valid
standards for correcting a moving object’s wind speed and direction heading. Details on thealgorithm used
are included in the Appendix Para 9.1.
2.1.11 Compass Declination
Declination is the magnetic declination (the angle between Magnetic North and True North) in degrees.
This is a correction factor that is addedto theMagnetic North heading from the compass.
Map and declination figures in decimal figures can be obtained from:
http://www.geosats.com/magdecli.html
http://www.ngdc.noaa.gov/geomag/declination.shtml
2.1.12 Solar (GMX101, GMX301, GMX501, GMX531, GMX541 and GMX551)
MaxiMet uses a high quality Hukseflux LPO2 second class Solar Radiation/Pyranometer which complies
with ISO 9060. This highly accurate instrument uses thermopile technology to measure hemispherical solar
radiation from a 180 degree field of view angle.
2.1.13 GPS Option (GMX200, GMX240, GMX500, GMX531, GMX541, GMX550, GMX551
and GMX600)
MaxiMet uses a highly accurate GPS antenna receivermodule including a ceramic GPS patch antenna. The
module is capable of receiving signals from up to 48 GPS satellites and transferring them into position and
timing information that can be read over a serial port. Small size and high-end GPS functionality are
combined with low power consumption.
When GPS Speed and GPS Heading are available and GPS Speed transitions are above 5m/s, Corrected
Wind Speed shall be computed as the True Wind Speed using GPS Speed and GPS Heading.