Soil moisture sensors

PESSL INSTRUMENTS SOIL MOISTURE SENSOR PI54-D

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TECHNICAL SPECIFICATIONS

Order number: 600118 / 900012

The PI54-D soil moisture sensor has a larger volume of influence. It determines volumetric water content (VWC) by measuring the dielectric constant of the soil using capacitance technology and soil temperature. It is 10 cm long and thus measures 1 liter of soil, while high frequency minimizes salinity and textural effects which makes PI54-D accurate in most soils.

Necessary Interface to connect this sensor with iMETOS: 600069 / 900052, 600068 / 900051, 600167 / 900057 or 900173, 900174, 900175.

FEATURE	VALUE
Volumetric water content (VWC)	Range: 0−0.57 m3/m3 (0%−57% VWC) Resolution: 0.0008 m³/m³ (0.08% VWC) in mineral soils from 0−0.50 m³/m³ (0%−50% VWC) Accuracy: With standard calibration equation, 0.03 m³/m³ (3% VWC) typical in mineral soils that have solution electrical conductivity <10 dS/m NOTE: With soil-specific calibration, ±0.02 m³/m³ ( ±2% VWC) is typical in any soil.
Dimensions	16.0 cm (6.3 in) length; 3.3 cm (1.3 in) width; 0.8 cm (0.3 in) height
Prong length	10 cm (3.94 in)
Cable length	5 m or 10 m
Supply voltage (VIN to GND)	Minimum: 3.6 VDC at 12 mA Maximum: 15 VDC at 20 mA
Measurement duration	Maximum 10 ms
Temperature accuracy	-+0.3°C in the soil temperature (range -5°C to +25°C approx.)
Output	Digital

PI-Profile Probe

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TECHNICAL SPECIFICATIONS

Order number: 600196 / 900260 (60 cm), 600197 / 900261 (90 cm)

The PI-Profile Probe system is ideal for broad-acre row crops like corn, cotton, alfalfa and soybeans, as well as all permanent crops. Due to its special design where the sensor and the cable
are trenched below the surface, there is no need for annual installation and removal of soil sensors from the field. The sensor comes with a 5-meter cable and watertight rapid connector so the in-field telemetry can be removed only during tillage, seeding, or harvest and moved back in after that. Highly scalable with a low total cost of ownership; no annual installation and removal! The PI-Profile Probe is available with 60 cm and 6 sensors (every 10 cm) and with 90 cm and 6 sensors (every 15 cm), which measure volumetric water content and soil temperature in the profile.

Necessary Interface to connect this sensor with METOS: SDI12

FEATURE	VALUE
Probe lengths	from 60 cm to 90 cm
Probe diameter	25 mm
Number of sensors	60 cm probe: one sensor every 10 cm 90 cm probe: one sensor every 15 cm
Moisture (VWC) range	Oven dry to saturation
Method	FDR
Resolution	0.01 %
Moisture precision	±0.03 % vol
Operating temperature range	-20 °C to 60 °C
Temperature resolution	0.2 °C
Cable length	5 m

Sentek Drill & Drop

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TECHNICAL SPECIFICATIONS

Order number: 600098 / 900104, 600099 / 900106, 600100 / 900107, 600101 / 900108, 600102 / 900109, 600103 / 900110, 600104 / 900111, 600105 / 900112, 600106 / 900113, 600107 / 900114

Sentek Drill & Drop probe provides the user with great flexibility for precision monitoring of temperature, water and salinity (Triscan) at multiple depths in a soil profile. Available in five lengths: 10 cm, 30 cm, 60 cm, 90 cm and 120 cm with sensors fixed at every 10 cm increment.

Necessary Interface to connect this sensor with iMETOS: 600150/900105.

FEATURE	VALUE
Probe lengths	10 cm (4”) / 30 cm (12”) / 60 cm (24”) / 90 cm (36”) / 120 cm (48”)
Number of sensors	1 / 3 / 6 / 9 / 12
Outer Probe Diameter (Top-Bottom)	24-24.5 mm / 28-29.5 mm / 27-29.5 mm / 26-30 mm / 24.5-29.5 mm
Moisture (VWC) range	Oven dry to saturation
Method	Capacitance based technology
Resolution	Moisture (VWC): 1:10000 Salinity (Triscan) (VIC, Volumetric Ion Content): 1:6000 Temperature: 0.3 °C
Moisture precision	±0.03 % vol.
Temperature accuracy	±2 °C at 25 °C
Operating temperature range	-20°C to +60°C

IRROMETER WATERMARK SOIL MOISTURE SENSOR

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TECHNICAL SPECIFICATIONS

Order number: 600120 / 900010

The Watermark Sensor consists of two concentric electrodes buried in a special reference matrix material that is held in place by a synthetic membrane. The matrix material has been selected to reflect the maximum change of electrical resistance over the growth range of crop production, as well as to neutralize the effect of soil salinity. In operation, soil moisture is constantly being absorbed or released and the electrical resistance between the electrodes changes. This resistance is read and logged by the weather station.

The sensor is manufactured from non-corrosive materials and lasts up to three years.

Necessary Interface to connect this sensor with iMETOS: 600068 / 900051, 600167 / 900057, 900174, 900175.

FEATURE	VALUE
Size	2.2 cm diameter x 5 cm length
Measuring Principle	Soil water tension correlated with electrical resistance in granular matrix
Working range	0 to 200 kPa
Precision	5%
Evaluation	Analog
Cable	3.5m / 10m

IRROMETER TENSIOMETER

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TECHNICAL SPECIFICATIONS

Order number: TNS101

The instrument measures soil water tension (or suction). This value represents the energy a plant’s root system uses to draw water from the soil. Understanding soil moisture dynamics helps the user make informed irrigation scheduling decisions, resulting in improved yield quantity and quality while reducing water, fertilizer, labour and energy costs. Available in different lengths: 15 cm, 30 cm, 45 cm, 60 cm and 90 cm.

Necessary Interface to connect this sensor with iMETOS: 600069 / 900052, 600068 / 900051, 600167 / 900057 or 900173, 900174, 900175.

FEATURE	VALUE
Instrument body materials	Butyrate body, ceramic tip, neoprene stopper
Weight	30 cm weights 0.439 kg. It increases 0.114 kg per 30 cm
Ceramic tip	White tip – used for most soil types
Operating suction	0-90 kPa
Operating temperature range	0°C to 50°C
Reservoir dimensions	Height: 120-130 mm including cap; Diameter: 51-55 mm including cap
Body tube dimensions	Lenght: ranges from 15 to 90 cm Diameter: 22 mm