SNiP-MPS For Soil Water Potential
The SNiP-MPS is a 'Sensor Node Integrated Package' for LoRaWAN or CAT-M1 communication of real-time soil matric potential and temperature measurements for continuous soil monitoring.
The SNiP-MPS
The base SNiP-MPS integrates 1x S-NODE and 1x Tensiomark soil moisture sensor to a site’s unique network, communication and power requirements. The S-NODE can support an added 3x Tensiomark devices.
The Tensiomark measures soil water tension from pF 0 up to pF 7 (1 up to 10,000,000 hPa); maintenance-free and frost resistant – suited to general monitoring of soil suction within or under structures of buildings, roadways and mine sites.
See Further Specifications on the S-NODE
See Further Specifications on the Tensiomark
S-NODE
The S-NODE (for Environmental Monitoring) has been designed to support the broad suite of SDI-12 based environmental sensors. The S-NODE can support sensors with higher power requirements; a solar panel can charge either the internal lithium-ion battery or both the node and sensor can be powered by an external 12V system (e.g. battery or mains source).
A decoder suitable for TTN will be provided based upon sensor configuration.
- LoRaWAN™ low-power long-range connectivity
- Supports the full range of SDI-12 commands, and sensors requiring constant excitation.
- Optional CAT-M1
- Solar rechargeable Lithium-ion, Single use LiSOCl2, or external 12V power options
- Optional Multi-constellation GNSS
- AS923, AU915 and US915 available, with other region plans available upon request.
- Standard IP65 enclosure, optional IP67
Tensiomark
Tensiomarks measure a special aspect of soil moisture, the soil matric potential. The matric potential (synonyms: pressure head, tension, or water potential) is an expression for the binding forces of water to the soil matrix and indicates the energy acting on the soil water and keeping it against the force of gravity inside the soil matrix. Because of adsorption and capillary forces the soil causes a water tension on the soil water. This matric potential is the highest at low water contents and decreases with increasing water content. The relation between matric potential and water content is shown in Fig. 1 for three different soil textures:
Key Features:
- Sensor covers complete measuring range (pF 0-7; 1-10.000.000 hPa)
- Maintenance-free and frost resistant
- Unlimited measuring range (no measurement gaps in summer due to dehydration)
- Fast response to moisture changes
- Measurement of soil temperature (only in SDI-12-mode)
- Depending on application different calibration classes are available (see technical data)
| Measuring principle | Heat Capacity |
| Ranges | pF 0~pF 7,0 ≙ 1~10.000.000 hPa -40~+80 °C |
| Resolution | 0.01 pF, 0,1 °C |
| Accuracy | ca. +/- 30 hPa & 5 % FS = 0,35 pF Note: In general, best results will be produced with sensing cycles of 15 minutes because 15 minutes cycles are used in the calibration process |
| Shortest Sensing Cycle | 15 min |
| Waiting time | 15-20 sec (Duty cycle of the data logger before measurement) |
| Output signal | digital (SDI-12), optional analog |
| SDI-12-Signal | pF-Wert 0~7, Temp. in °C |
| Analog signal | -40°~60°C – Sensors can be used at higher temperatures under some conditions. Contact us for more details. Water potential measurements will not be accurate below 0°C. |
| Power supply | 7~14 V DC (12 V recommended) |
| Dimensions | L = 125 mm, D = 20 mm |
| Cable | Standard length: 5 m. Min. bending radius: 90 mm Sheath: PUR, UV-resistant, temperature range –30~+95 °C |
| Sensor Body | Stainless steel |
| Sensor Head | Ceramic |