Specifications
Soil Moisture: Volumetric Water Content (VWC)
Measurement Range: In soil: 0 to 0.550 m³/m³ (volumetric water content)
Accuracy: ±0.02 m³/m³ (±2%) in most soils typical from 0° to 50°C (32° to 122°F)*
Resolution: 0.001 m³/m³
Temperature
Measurement Range: -20° to 70°C (-4° to 158°F)
Accuracy: ±0.5°C (0.9°F)
Resolution: 0.1°C (0.18°F)
Depths Measured (see below)
RXW-GP3A-xxx: 45 cm (18 inches) total; three soil moisture zones, six temperature depths
RXW-GP4A-xxx: 60 cm (24 inches) total; four soil moisture zones, six temperature depths
RXW-GP6A-xxx: 90 cm (35 inches) total; six soil moisture zones, nine temperature depths
Wireless Mote
Operating Temperature Range: Sensor: -20° to 70°C (-4° to 158°F)
Mote: -25° to 60°C (-13° to 140°F) with rechargeable batteries
Mote: -40° to 70°C (-40° to 158°F) with lithium batteries
Radio Power: 12.6 mW (+11 dBm) non-adjustable
Transmission Range: Reliable connection to 457.2 m (1,500 ft) line of sight at 1.8 m (6 ft) high
Transmission Range: Reliable connection to 609.6 m (2,000 ft) line of sight at 3 m (10 ft) high
Wireless Data Standard: IEEE 802.15.4
Radio Operating Frequencies: RXW-GPxA-900: 904–924 MHz
Radio Operating Frequencies: RXW-GPxA-868: 866.5 MHz
Radio Operating Frequencies: RXW-GPxA-921: 921 MHz
Radio Operating Frequencies: RXW-GPxA-922: 916–924 MHz
Modulation Employed: OQPSK (Offset Quadrature Phase Shift Keying)
Data Rate: Up to 250 kbps, non-adjustable
Duty Cycle: <1%
Maximum Number of Motes: Up to 50 wireless sensors or 336 data channels per one HOBO RX station
Logging Rate: Maximum logging interval: 18 hours
Logging Rate: Recommended minimum logging interval: 5 minutes year round (solar power with rechargeable batteries), 10 minutes (non-rechargeable lithium batteries)
Number of Data Channels: RXW-GP3A-xxx: 10
Number of Data Channels: RXW-GP4A-xxx: 11
Number of Data Channels: RXW-GP6A-xxx: 16
Battery Type / Power Source
Two AA 1.2V rechargeable NiMH batteries: Powered by built-in solar panel
Two AA 1.5 V non-rechargeable lithium batteries: Operating conditions -40 to 70°C (-40 to 158°F)
Battery Life
With NiMH batteries: Typical 3–5 years (temperature range -20° to 40°C / -4°F to 104°F, positioned toward sun); operation outside range reduces battery life
With non-rechargeable lithium batteries: 1 year with a 10-minute logging interval
Memory
Capacity: 16 MB
Dimensions
RXW-GP3A-xxx sensor length: 53.2 cm (20.9 inches)
RXW-GP4A-xxx sensor length: 68.2 cm (26.9 inches)
RXW-GP6A-xxx sensor length: 98.2 cm (38.7 inches)
Sensor diameter: 3 cm (1.2 inches)
Cable length: 3.5 m (11 ft 6 in)
Mote: 16.2 x 8.59 x 4.14 cm (6.38 x 3.38 x 1.63 inches)
Weight
RXW-GP3A-xxx sensor: 351 g (12.4 oz)
RXW-GP4A-xxx sensor: 408 g (14.4 oz)
RXW-GP6A-xxx sensor: 526 g (18.6 oz)
Cable: 180 g (6.5 oz)
Mote: 226 g (7.97 oz)
Materials
Sensor: Polycarbonate housing encasing epoxy sealed circuit board
Cable: Polyurethane
Mote: PCPBT, silicone rubber seal
Environmental Rating
Mote: IP67, NEMA 6
