Introduction to Sensor
The TEROS 11 is a rugged, long-life soil moisture and temperature sensor designed for reliable monitoring in demanding field environments. With a large 1010 mL volume of influence, reduced sensor-to-sensor variability, and advanced 70 MHz capacitance technology, it delivers consistent and accurate soil measurements. Its durable epoxy body and easy installation make it ideal for long-term soil monitoring applications.
Specifications
Specifications
Volumetric Water Content
| Parameter | Specification |
|---|---|
| Range | Mineral Soil Calibration: 0.00–0.70 m³/m³ Soilless Media Calibration: 0.0–1.0 m³/m³ Apparent Dielectric Permittivity (εa): 1 (air) to 80 (water) NOTE: The VWC range is dependent on the media the sensor is calibrated to. A custom calibration will accommodate the necessary ranges for most substrates. |
| Resolution | 0.0010 m³/m³ |
| Accuracy | Generic Calibration: ±0.03 m³/m³ (±3.00% VWC) typical in mineral soils that have solution EC <8,000 μS/cm Medium Specific Calibration: ±0.01–0.02 m³/m³ in any porous medium Apparent Dielectric Permittivity (εa): 1–40 (soil range), ±1 εa (unitless) 40–80, 15% of measurement |
Measurement Specifications
| Parameter | Specification |
|---|---|
| Dielectric Measurement Frequency | 70 MHz |
| Measurement Volume | See comparison article |
| Temperature – Range | −40 to +60 °C |
| Temperature – Resolution | 0.1 °C |
| Temperature – Accuracy | ±1.0 °C from −40 to 0 °C±0.5 °C from 0 to +60 °C NOTE: Temperature measurement, for applicable sensors, may not be accurate if sensor is not fully immersed in the medium of interest, due to longer equilibration time. |
Communication Specifications
| Parameter | Specification |
|---|---|
| Output | DDI serial or SDI-12 communication protocol |
| Data Logger Compatibility | METER ZL6, EM60, and Em50 data loggers or any data acquisition system capable of 4.0- to 15-VDC power and serial or SDI-12 communication See compatibility chart |
Physical Specifications
| Parameter | Specification |
|---|---|
| Dimensions | Length: 9.4 cm (3.70 in) Width: 2.4 cm (0.95 in) Height: 7.5 cm (2.95 in) |
| Probe Length | 5.5 cm (2.17 in) |
| Operating Temperature Range | Minimum: -40.00 °C Typical: NA Maximum: 60.00 °C NOTE: Sensors may be used at higher temperatures under certain conditions; contact Customer Support for assistance. |
| Cable Length | 5 m (standard) 75 m (maximum custom cable length) NOTE: Contact Customer Support if a nonstandard cable length is needed. |
| Cable Diameter | 0.165 ±0.004 (4.20 ± 0.10 mm) with minimum jacket of 0.030 (0.760 mm) |
| Connector Types | 3.5-mm stereo plug connector or stripped and tinned wires |
| Stereo Plug Connector Diameter | 3.5 mm |
| Conductor Gauge | 22-AWG / 24-AWG drain wire |
Electrical and Timing Characteristics
| Parameter | Minimum | Typical | Maximum |
|---|---|---|---|
| Supply Voltage (VCC to GND) | 4.0 VDC | NA | 15.0 VDC |
| Digital Input Voltage (Logic High) | 2.8 V | 3.6 V | 5.0 V |
| Digital Input Voltage (Logic Low) | -0.3 V | 0.0 V | 0.8 V |
| Digital Output Voltage (Logic High) | NA | 3.6 V | NA |
| Power Line Slew Rate | 1.0 V/ms | NA | NA |
| Current Drain (During 25-ms Measurement) | 3.0 mA | 3.6 mA | 16.0 mA |
| Current Drain (While Asleep) | NA | 0.0 mA | NA |
| Power Up Time (DDI Serial) | 80 ms | NA | 100 ms |
| Power Up Time (SDI-12) | NA | 245 ms | NA |
| Power Up Time (SDI-12, DDI Serial Disabled) | 145 ms | 155 ms | 165 ms |
| Measurement Duration | 25 ms | NA | 150 ms |
Other
| Parameter | Specification |
|---|---|
| Compliance | EM ISO/IEC 17050:2010 (CE Mark) 2014/30/EU and 2011/65/EU EN61326-1:2013 and EN55022/CISPR 22 EN 55011:2016/A1:2017 (GROUP 1, CLASS A-RCM mark) Prop 56 warning EU Declaration of Conformity |
| GSA | View GSA details |
Features
Applications