Description

The GMX100 is a precipitation sensor in the MaxiMet range of compact weather stations and features an optical rain sensor. The sensor consists of 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 rain levels to be made. Algorithms then interpret the data of drop size and quantity to determine rain fall totals and intensity. The sensor can therefore provide data for exactly when rain starts and stops as well as the amount and intensity of the rainfall. The sensor also includes an integrated heater to ensure the sensor is kept clear of dew and condensation.

The GMX100 offers additional benefits over traditional tipping rain bucket rain sensors. Counting tips may not be accurate as rain may stop before the lever has tipped. When the next period of rain begins it may take no more than one or two drops to tip the lever. Tipping buckets also tend to underestimate the amount of rainfall, ie. not recording all of it, particularly in snowfall, heavy rainfall events or in high wind conditions. Finally, tipping rain buckets can be subject to vibration, whilst the GMX has no moving parts and isn’t affected by any movement. Rain buckets that are not securely mounted, or used in an offshore application, may be subject to false rain measurements due to motion causing the balance to tip.

The GMX100 has been designed as a complete rain sensor suitable for any installations, including those that may not be suitable for traditional rain sensors eg. Marine applications, where the motion on the sea could provide false values, or extreme environments where rainfall totals may not otherwise be accurately measured. This sensor can be easily integrated into remote weather station, weather buoys or fixed installations to work as a stand alone rainfall sensor or as part of a larger environmental monitoring system.

Features

• Lightweight and Robust Rain Sensor
• Provides: Rainfall Totals, Intensity and rainfall Y/N readings
• Rainfall totals available in mm or inches
• Integrated Heater
• No Moving Parts
• Low Power Mode
• Bolt fittings supplied for securing the unit to a vertical pipe of diameter 44.45mm
• MetSet and MetView software include

Precipitation Total.
Outputs Precipitation (Rain) Total reading, this is a one minute updated accumulated rain reading output once per second (with default output rate setting at 1Hz).
Is set to zero on MaxiMet power up.
Is set to zero when the clock reads 23:59:59 to 00 (midnight) and is the default setting.
For continuous measurement turn off Auto-reset of Total Precipitation using MetSet. Result e.g. 00000.4 (millimetres default).

Precipitation Intensity.
Outputs Precipitation (Rain) Intensity.
It is the sum of the last sixty lots of 1 minute accumulated Rain data. A new sum measurement is generated every minute.
It will be set to zero on MaxiMet power up.
Result e.g. 000.2 (millimetres default).

Precipitation Status.
Outputs Precipitation (Rain) Status as N or Y (No or Yes).
Changes N to Y when total precipitation is incremented.
Changes Y to N when total precipitation has not incremented in the last 60 seconds.
Result e.g. N (or Y).

Precipitation
Measurement Type: Optical
Output Range: 0 to >300mm/hr
Resolution: 0.2mm
Repeatibility: 3%
Sampling Rate: 1 Hz
Units: mm/hr, mm Total, mm/24Hr. inchs/hr, inchs Total, inchs/24Hr

Outputs
Output Rate: 1/s, 1/min, 1/hr
Digital Comms Modes: Serial RS232, RS422, RS485, SDI-12, NMEA, Modbus, ASCII
Analogue Outputs: Available via separate optional device

Power
Power Supply: 5 to 30vDC
Power (Nominal) 12vDC: 80mA continuous high mode. 0.7mA eco-power mode (1 hour polled)

Environmental Conditions
IP Rating: IP66
Operational Temperature Range: -40 to +70°C
EMC Standard: BS EN 61326:2013 FCC CFR47 Parts 15:109
CE Marking: Yes
ROHS: Yes
Weight: 0.3Kg
Country of Origin: UK