You need sensor longevity
Soil can be highly variable in space, requiring numerous measurements and frustrating amounts of your research dollars. Not to mention the extra cost and hassle of replacement sensors if you need long-term data. Make long-term, large sensor networks simpler, longer-lasting, and more affordable with the ultra-dependable TEROS 12 soil moisture and temperature sensor.
With you for the long haul—guaranteed
The culmination of our new TEROS water content line, the TEROS 12 soil moisture, temperature, and electrical conductivity sensor makes your life easier with a large volume of influence, reduced sensor-to-sensor variability, and a near-bulletproof form factor—which lasts up to 10 years in the field. These innovations, along with our well-published capacitance technology, an accuracy verification standard, and a blazing fast installation tool have combined to generate our most accurate, easy-to-use, highly durable—yet still economical—soil moisture sensor. In fact, we’re so confident about the long life of our TEROS sensor line, we’ve increased our standard warranty from one to three years.
Legendary technology—long-lasting performance
Backed by over 20 years of soil moisture research, the TEROS 12 combines METER’s trademark 70 MHz circuitry with an extremely ruggedized epoxy fill and securely attached, sharpened stainless steel needles that easily slip into the soil and are resistant to salts, so you can worry less about sensor deterioration. Very low power consumption and a high resolution provide increased precision over a longer period of time.
Small sensor lets you think bigger
The TEROS 12 delivers the best volume of influence to sensor size on the market so you’re less susceptible to soil variability errors. We’ve optimized the circuitry in this 9.4-cm sensor to deliver an incredible one-liter volume of influence (versus the 200 mL typical for most sensors). Most soil sensors that measure this much volume are 20 cm or longer, causing installation headaches. Not only that, you can cut your installation time in half or more when you install with the new Borehole Installation tool. The tool mistake-proofs installation, eliminating common errors that cause uncertainty in the data—like air gaps, or preferential flow.
The TEROS 12 uses a completely new calibration procedure that maximizes accuracy and minimizes sensor-to-sensor variability while keeping the cost reasonable. So you can be confident that every sensor you install is going to read exactly like the next one. Unlike other sensors on the market which spec an unverifiable ±1.0% VWC accuracy, the TEROS 12 was rigorously tested by our soil physicists across a challenging range of soil types and EC levels so you can be confident in the accuracy of your data.
Plus, TEROS sensor repeatability can be checked with an accuracy verification standard. No other soil moisture sensor has this ability. Just slide the verification clip onto a sensor and plug it into a logger. If it reads within the right range, your sensor is good to go.
Near-instant data gratification
Easy and reliable data collection is part of the TEROS experience. Combine the TEROS 12 with the new ZL6, where all data are connected and delivered in near-real time through the cloud. All you have to do is sit back and let the data flow.
Now you can have everything
We created the TEROS line to eliminate barriers to good accuracy: installation inconsistency, sensor-to-sensor variability, and sensor verification. The TEROS 12 is a long-life, accurate, easy-to-install sensor that combines METER’s legendary technology with an ultra-rugged form and a new calibration procedure to deliver an unbeatable price-to-performance ratio. If you’re planning a long-term large sensor network and want long-lasting performance for less work and less of your research budget, then choose the TEROS 12.
- Increased volume of influence (1010 mL)
- Easy installation with borehole installation tool (minimizes air gaps for cleaner readings)
- Dependable, long-life sensor
- Reduced sensor-to-sensor variability
- 3-year long-life guarantee
- Track solute and fertilizer movement with accurate EC measurement
- Check installation or troubleshoot with the ZSC Bluetooth sensor interface
- Repeatability can be checked with an accuracy verification standard
- Robust, epoxy body for tough field conditions
- Minimizes salinity and textural effects by using 70 MHz frequency capacitance technology
- Steel needles cut through the soil for better soil-sensor contact
- Easy-to-use SDI-12 communication for non-METER data loggers
- Ferrite core eliminates cable noise
- See comparison of all TEROS water content sensors—>
|Volumetric water content (VWC)|
|Dielectric measurement frequency|
Range: −40 to 60 °C
|Bulk electrical conductivity (ECb)|
Range: 0 to 20 dS/m (bulk)
DDI serial or SDI-12 communications 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)
Length: 9.4 cm (3.70 in)
5.5 cm (2.17 in)
5 m (standard)
0.165±.004 (4.20±.10mm) with min. jacket of .030 (.76mm)
3.5-mm stereo plug connector or stripped and tinned wires
|Stereo plug connector diameter|
22 AWG/24 AWG drain wire
|ELECTRICAL AND TIMING CHARACTERISTICS|
|Supply voltage (VCC) to GND|
Minimum: 4.0 VDC
|Digital input voltage (logic high)|
Minimum: 2.8 V
|Digital input voltage (logic low)|
Minimum: –0.3 V
|Digital output voltage (logic high)|
|Power line slew rate|
Minimum: 1.0 V/ms
|Current drain (during 25-ms measurement)|
Minimum: 3.0 mA
|Current drain (while asleep)|
|Operating temperature range|
Minimum: –40 °C
|Power up time (DDI serial)|
Minimum: 80 ms
|Power up time (SDI-12)|
|Power up time (SDI-12, DDI disabled)|
Minimum: 145 ms
Minimum: 25 ms
Manufactured under ISO 9001:2015
California requires the following notice:
⚠️ WARNING: This product may contain chemicals including ethylene glycol, lead, nickel, styrene and cadmium, which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov
Learn more with articles, case studies, demos, webinars
- ZENTRA Cloud request a demo
- TEROS 12 cited publications
- How to install soil moisture sensors—better, faster, and for higher accuracy
- The researcher’s complete guide to soil moisture
- How to calibrate soil moisture sensors
- Soil Moisture 101: Need to know basics
- Soil Moisture 102: Water content methods—demystified
- SEE ALL TEROS 12 KNOWLEDGE BASE ARTICLES
- SEE ALL TEROS 12 WEBINARS
- SEE ALL TEROS 12 CASE STUDIES
Have a question or problem? Our support team can help.
We manufacture, test, calibrate, and repair every instrument in-house. Our scientists and technicians use the instruments every day in our product testing lab. No matter what your question is, we have someone who can help you answer it.
Phone Europe: +49 89 12 66 52 0