Product Overview
The OHTS1021 is a multi-layer soil parameter monitoring sensor based on the dielectric constant measurement principle. Utilizing a stratified measurement structure, it enables dynamic observation of soil moisture content, temperature, and electrical conductivity at different depths. The device is equipped with standard 3-layer to 5-layer soil parameter detection capability, with a measurement point spacing of 10cm. An optional integrated tri-axial tilt sensor is available for monitoring soil and equipment attitude changes.
The device features a PVC tubular housing structure that allows transmission of near 1GHz high-frequency detection waves, avoiding interference from soil salt ions, fertilizers, pesticides, and irrigation activities on measurement results. The circuit section employs potting processing, achieving IP68 protection rating for the below-ground portion. The communication interface adopts standard ModBus-RTU protocol with RS485 bus transmission, supporting a maximum communication distance of 2000m, and accepts 10 ~ 30V wide-range DC power supply.
Features
- Multi-Layer Structural Design: Supports synchronous monitoring of 3 to 5 layers of soil parameters with 10cm inter-layer spacing, providing comprehensive soil profile data.
- Dielectric Constant Measurement: Utilizes TDR principle to measure soil volumetric water content; measurement electrodes do not contact soil directly, avoiding electrochemical corrosion and polarization interference.
- Robust PVC Housing: PVC tubular housing with excellent wave transmission performance and resistance to soil chemical corrosion, ensuring long-term stability in harsh agricultural environments.
- Optional Advanced Functions: Available with soil electrical conductivity monitoring (0 ~ 20000μS/cm range) and tri-axial tilt sensor for static and dynamic angle monitoring.
- Industrial Grade Protection: Potting process treatment achieves IP68 protection rating for below-ground portions, ensuring reliable operation in soil conditions.
- Flexible Communication: Standard ModBus-RTU protocol with RS485 interface supporting multi-level bus networking up to 2000m communication distance.
- Wide Power Range: 10 ~ 30V wide-range DC power supply with low power consumption design suitable for solar-powered remote installations.
- High Frequency Detection: Near 1GHz high-frequency detection waves provide accurate measurements unaffected by soil salinity or chemical treatments.
Applications
- Agricultural irrigation automation control systems
- Soil moisture and drought monitoring networks
- Soil parameter acquisition for meteorological observation stations
- Hydrological and water resource monitoring projects
- Water conservancy engineering storage and diversion status monitoring
- Precision agriculture and environmental monitoring stations
- Geological disaster early warning soil parameter monitoring
- Long-term observation of soil physicochemical properties for scientific research
Technical Specifications
| Parameter Category | Parameter Item | Specification |
|---|---|---|
| Environmental Adaptability | Operating Temperature | -40℃ ~ 80℃ |
| Measurement Range | Soil Moisture | 0 ~ 100% |
| Soil Temperature | -15℃ ~ 35℃ | |
| Soil Electrical Conductivity | 0 ~ 20000μS/cm | |
| Tilt Angle | -90° ~ 90° | |
| Measurement Accuracy | Soil Moisture | ±5% (@50%, 25℃) |
| Soil Temperature | ±0.5℃ (25℃) | |
| Soil Electrical Conductivity | 0 ~ 10000μS/cm range: ±3%FS; 10000 ~ 20000μS/cm range: ±5%FS (Brown soil, 60%, 25℃) | |
| Tilt Angle-X/Y Axis | Static accuracy: ±0.1°; Dynamic accuracy: ±0.5° | |
| Tilt Angle-Z Axis | Static accuracy: ±0.5° (dynamic has integration error) | |
| Temperature Characteristics | Tilt Temperature Drift | ±(0.5° ~ 1°), (-40°C ~ +60°C) |
| Structural Parameters | Measurement Point Spacing | 10cm |
| Electrical Parameters | Power Supply | 10 ~ 30V DC |
| Power Consumption (3-layer) | 0.7W | |
| Power Consumption (5-layer) | 0.96W | |
| Output Signal | RS485 (ModBus-RTU Protocol) | |
| Performance Indicators | Response Time | ≤60s |
| Material and Protection | Housing Material | PVC plastic tube |
| Protection Rating | IP68 for below-ground portions |
Note: When soil temperature is below 0℃, soil moisture and electrical conductivity readings are for reference only.
Physical Specifications
| Parameter Item | Specification Description |
|---|---|
| Housing Material | PVC plastic tube |
| Protection Rating | IP68 for below-ground portions |
| Measurement Point Spacing | 10cm |
| Layer Configuration | 1 temperature observation point at ground level, 1 soil temperature and moisture measurement point every 10cm below ground |
FAQ
Q: What measurement principle does the OHTS1021 use?
A: The sensor utilizes the dielectric constant method based on TDR principle to measure soil volumetric water content with non-contact electrodes.
Q: What is the protection rating of the device?
A: The below-ground portion achieves IP68 protection rating through potting process treatment, providing excellent resistance to soil chemical corrosion.
Q: What happens when soil temperature drops below 0 degrees Celsius?
A: When soil temperature is below 0 degrees Celsius, soil moisture and electrical conductivity readings are for reference only.
Q: How should the sensor be installed in sandy or clay soils?
A: For sandy soil, pour at least 5 liters of water into the hole before grouting to moisten the walls. For clay soil, soak the extracted soil for more than 4 hours to soften before creating the slurry.
Q: Can this device be used as a safety or emergency stop device?
A: No, this device is strictly prohibited from use as a safety device or emergency stop device, nor shall it be used for other applications where equipment failure may cause personal injury.