SOLYX 14
SOLYX 14
Measure accurate water content and pore water EC with revolutionary CDX technology





The toughest, longest-lasting soil moisture sensor, built with new CDX technology for accurate measurements in a wide range of soil salinity and temperatures.
- Measures dielectric permittivity, soil moisture, temp, bulk EC, and pore water EC with Complex Dielectric through intersections (learn about CDX)
- Achieve accurate water content measurements—even in high salinity soils
- Built tough for long-term deployment in harsh conditions
The future of soil moisture monitoring starts here
Get more out of every measurement with the SOLYX 14 featuring CDX (learn about CDX). Continuously monitor dielectric permittivity, soil temperature, bulk electrical conductivity (ECb), volumetric water content (VWC), and pore water electrical conductivity (ECw). Designed and proven through rigorous durability testing, the SOLYX 14 is METER’s toughest, longest-lasting sensor yet—ensuring you get consistent, accurate soil moisture data season after season, year after year.
Soil moisture—evolved
Accurate soil moisture measurement relies on more than just collecting and processing data. To truly trust data validity, sensors should be easy to consistently install correctly and durable enough to endure years of use in harsh environmental conditions. METER instruments are chosen by scientists, growers, and engineers worldwide for their accuracy, and the CDX technology behind the SOLYX 14 marks the next advancement in soil moisture measurement.
Redefining what’s possible with CDX technology
Developed by METER scientists, Complex Dielectric through intersection, or CDX, is a patented impedance technology that makes accurate measurement of VWC, EC, and soil temperature possible in soil, substrates, and porous material across a wide range of salinities and temperatures.
By measuring complex dielectric permittivity, the SOLYX 14 independently measures both the real dielectric permittivity (related to water content) and the imaginary dielectric permittivity (which is influenced by salts and lossy clays). That means you can achieve accurate soil moisture measurements in more places than ever before.
Consistent installation = higher accuracy
The more consistent the sensor installation, the more reliable the data. That’s why the SOLYX 14 can be installed using the same Borehole Installation Tool (TBIT) as the TEROS soil moisture sensors, which minimizes air pockets and ensures solid sensor-to-soil contact. The TBIT firmly inserts the sensor into the side of a 10 cm borehole at depths of up to 5 meters, making installation quicker, easier, and more accurate. Once installed, setup is as simple as plug-and-play with METER data loggers, sending real-time data to ZENTRA Cloud for remote data visualization, computation, and collaboration.
Engineered for endurance
Whether you’re measuring soil moisture over a season or a decade, SOLYX 14 delivers long-term stability and reliability. Its low-power requirements make it ideal for permanent installation—even at remote sites. Robust stainless-steel needles, a high-durability cable, and epoxy fill enable this sensor to provide research-grade accuracy year after year, even under harsh conditions. We’re so confident about the long life of the SOLYX 14, we’ve increased our standard warranty from one to three years.
Feature summary
- CDX technology accurately measures dielectric, soil moisture, and EC in a wide range of soil types, salinities, and temperatures
- Sensor-to-sensor consistency ensures trustworthy measurements
- Simplify sensor installation with the Borehole Installation Tool
- On-board diagnostic tool checks sensor functionality with every measurement
- Robust design with epoxy fill, stainless steel needles, and cable with braided metal shield to protect against damage
- Ideal for long-term deployment
Measurement Specifications
Volumetric Water Content (VWC) Range
Mineral Soil Calibration: 0.00–0.72 m3/m3
Real Dielectric Permittivity (εr): 1 (air) to 80 (water)
Note: The VWC range is dependent on the media the sensor is calibrated to. A custom calibration will accmmodate the necessary ranges for most substrates.
Volumetric Water Content (VWC) Resolution
0.001 m3/m3
Volumetric Water Content (VWC) Accuracy
Generic Calibration: ±0.03 m3/m3 typical in mineral soils
Medium Specific Calibration: ±0.01 m3/m3 in any porous medium
Real Dielectric Permittivity (εr): ± 1εr (unitless)
Dielectric Measurement Frequency
70 MHz
Temperature
Range: –40 °C to +60 °C
Resolution: 0.1 °C
Accuracy: ±0.3 °C from 0 to +60 °C, ±1 °C from –40 to 0 °C
Note: Temperature measurement for applicable sensor may not be accurate if sensor is not fully immersed in the medium of interest due to longer equilibration time.
Bulk Electrical Conductivity (EC)
Range: 0–20 dS/m (bulk)
Resolution: 0.001 dS/m
Accuracy: ±(5% + 0.01 dS/m) from 0–10 dS/m
Accuracy: ±8% from 10–20 dS/m
Communication Specifications
Output
DDI-serial
SDI-12 communication protocol
Data Logger Compatibility
METER ZL6 data loggers and any data acquisition system capable of 4.0- to 15.0-VDC power and serial or SDI-12 communication.
Physical Specifications
Dimensions
Length: 8.9 cm (3.50 in)
Width: 2.5 cm (0.98 in)
Height: 7.5 cm (2.96 in)
Needle Length
5.5 cm (2.17 in)
IP Rating
IP 65
IP 67
Operating Temperature Range
Minimum: –40 °C
Typical: N/A
Maximum: 60 °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
0.54 ± 0.01 cm (0.212 ± 0.004 in) with a minimum jacket of 0.076 cm (0.030 in)
Connector Types
3.5 mm stereo plug connector or stripped and tinned wires
Conductor Gauge
22-AWG / 24-AWG drain wire
Electrical and Timing Characteristics
Supply Voltage (VCC) to GND
Minimum: 4.0 VDC continuous
Typical: N/A
Maximum: 15.0 VDC continuous
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: N/A
Typical: 3.6 V
Maximum: N/A
Power Line Slew Rate
Minimum: 1.0 V/ms
Typical: N/A
Maximum: N/A
Required Supply Current
Minimum: 16.0 mA
Typical: N/A
Maximum: N/A
Current Drain (During Measurement)
Minimum: N/A
Typical: 4.43 mA
Typical: NOTE: 372 ms ?M! command
Maximum: N/A
Current Drain (While Asleep)
Minimum: N/A
Typical: 0.03 mA
Maximum: 0.06 mA
Power Up Time (DDI Serial)
Minimum: N/A
Typical: 100 ms
Maximum: 350 ms
Power Up Time (SDI-12)
Minimum: N/A
Typical: 260 ms
Maximum: N/A
Power Up Time (SDI-12, DDI Disabled)
Minimum: N/A
Typical: 170 ms
Maximum: N/A
Measurement Duration
Minimum: N/A
Typical: 50 ms
Maximum: N/A
Other
Compliance
EM ISO/IEC 17050:2010 (DoC upon request)
2014/30/EU (EMC) via EN 61326-1:2013
2011/65/EU (RoHS) via EN 63000:2018
CISPR 11:2024 Group 2 Class A

