Introduction to Sensor
The TEROS 22 is a high-accuracy matric water potential sensor designed to measure soil water potential across the full range for reliable soil moisture monitoring. Its precalibrated design enables quick and easy installation, while onboard temperature measurement provides additional soil condition data. With low maintenance requirements and fast installation and removal, it is ideal for efficient long-term soil monitoring.
Specifications
Specifications
Measurement Specifications
| Parameter | Specification |
|---|---|
| Water Potential | Range: 0 to –100,000 kPa (1.70 to 6.00 pF) Resolution: 0.1 kPa Accuracy: ±(10% of reading + 2 kPa) from –100 to –5 kPa NOTE: TEROS 22 can read up to 0 kPa when on a wetting path. The air entry of the soil limits the performance of the sensor to –5 kPa on the drying curve. NOTE: TEROS 22 is not well calibrated beyond –100 kPa. For more information on using the TEROS 22 beyond this range, see Section 3.3.3 in the user manual. |
| Dielectric Measurement Frequency | 70 MHz |
| Temperature | Range: –40.00 to +60.00 °C Resolution: 0.10 °C Accuracy: ±1.00 °C |
Communication Specifications
| Parameter | Specification |
|---|---|
| Output | DDI serial or SDI-12 communication protocol |
| Data Logger Compatibility | METER ZL6 and EM60 data loggers or any data acquisition system capable of 4.0- to 15-VDC power and serial or SDI-12 communication |
Physical Specifications
| Parameter | Specification |
|---|---|
| Dimensions | Diameter: 1.7 cm (0.67 in) Length: 17 cm (6.7 in) Length with optional extensions: 40, 80, and 120 cm (15.7, 31.5, and 47.3 in) |
| Sensor Diameter | 1.7 cm (0.67 in) |
| Operating Temperature Range | Minimum: –40.00 °CTypical: NA Maximum: +60.00 °C NOTE: Sensors may be used at higher temperatures under certain conditions; contact Customer Support for assistance. |
| Cable Length | Standard: 5 m Maximum custom cable length: 75 m NOTE: Contact Customer Support if a nonstandard cable length is needed. |
| Connector Types | Stereo plug connector or stripped and tinned wires |
| Connector Size | 3.50 mm |
| Conductor Gauge | 22-AWG \ 24-AWG ground wire |
Electrical and Timing Characteristics
| Parameter | Specification |
|---|---|
| Supply Voltage (VCC to GND) | Minimum: 4.0 VDC Typical: NA Maximum: 15.0 VDC |
| Digital Input Voltage (Logic High) | Minimum: 2.8 V Typical: 3.6 V Maximum: 5.0 V |
| Digital Input Voltage (Logic Low) | Minimum: –0.3 V Typical: 0.0 V Maximum: 0.8 V |
| Digital Output Voltage (Logic High) | Minimum: NA Typical: 3.6 V Maximum: NA |
| Required Supply Current | Minimum: 15 mA Typical: NA Maximum: NA |
| Power Line Slew Rate | Minimum: 1.0 V/ms Typical: NA Maximum: NA |
| Power Up Time (DDI Serial) | Minimum: NA Typical: 100 ms Maximum: 350 ms |
| Time before sensor is responsive to SDI-12 commands (DDI serial enabled) | Minimum: NA Typical: 260 ms Maximum: 500 ms |
| Time before sensor is responsive to SDI-12 commands (DDI serial disabled) | Minimum: NA Typical: 170 ms Maximum: NA |
| Measurement Duration | Minimum: NA Typical: 50 ms Maximum: NA |
Other
| Parameter | Specification |
|---|---|
| Compliance | EM ISO/IEC 17050:2010 (CE Mark) EN 55011:2016 / A1:2017 (RCM Mark) |
| Safety Information | Prop 65 warning |
| Declaration | EU Declaration of Conformity |
Features
Applications