METER T8 Tensiometer – Water Potential and Temperature


To refill, or not to refill?  That is the question.

The truth about tensiometers is that they’re hard to integrate into complex sensor networks, and they can be damaged or destroyed by bad weather. Plus, they need to be refilled, which means constantly pulling the tensiometer out of the soil to check the water level. Tensiometers simply haven’t been a practical part of a modern sensor network. Until now.


With the T8 Tensiometer, our goal was to design an instrument that was easy to use, reliable, and practically bulletproof when it comes to harsh weather.  Not only that, an external refilling tube and plug and play capability make this the first tensiometer that works well in a large sensor network.

Master of the quick change–even under pressure

The highly-responsive T8 reacts much faster to changing soil conditions because of its small water volume, enabling you to measure even the most minute changes in water potential—something lower-quality tensiometers cannot do. It measures matric potential in the wet range, where most water movement occurs, enabling you to predict whether water will move and where it will go. In addition, the T8 still functions under positive pressure, meaning when the ground becomes saturated, it measures how high the water level is above saturation, important for understanding slope stability.

A refill gauge that’s always on the level

We’ve outfitted the T8 with an external refilling tube. No more pulling the tensiometer out of the ground. When it’s time to refill, the T8 can be filled externally without ever having to remove it, saving you an incredible amount of time and hassle. Not only that, a water level indicator lets you know when it’s time to refill, so you never have to guess if your data are valid.

Never leaves you in the cold

Engineered specifically for long-term, year-round use, the T8 is extremely robust, frost-proof, and reliable. It offers an integrated temperature sensor, as well as lightning protection. Thanks to its solid construction and impact-resistant plastic, the T8 Tensiometer is unaffected by tough, year-round use in the field.

It’s as easy as plug and play

To save you even more time, the T8 is incredibly easy to install. Not only is it plug and play with METER data loggers, but its digital sensor interfaces with SDI-12 and RS485 and is easily integrated into large sensor networks, even those operated by a single data logger.

Uncompromising, peerless design for long-term measurement

Reliability. Versatility. Ease-of-use. Precision. Over 25 years of German engineering has made the T8 Tensiometer into one of the most accurate, robust tensiometers in its class, saving you time and hassle and making your life much easier.

Ceramic cup

High-strength special ceramic with homogeneous porosity
Length: 60 mm
Diameter: 24 mm

Tensiometer shaft

Various lengths available (standard 200 mm)
Diameter: 25 mm
Material: acrylglass 19/25 mm
**Please indicate shaft length on your order**


Soil water tension: ± 0.5 kPa
Temperature: ± 0.2 °C (-10 to 10 °C), ± 0.5 °C (-30 to 70 °C)


0.1 kPa

Output signal analog

Selectable ranges: 2 x 0 … 1 V / 2 V / 5 V

Output signal digital

RS485 tensioLINK, SDI-12

Current consumption

7 mA

Measuring range soil water tension

+100 to -85 kPa

Delivery contents

Shaft water protection cover, calibration certificate, refilling syringe, user manual

Measuring range temperature

-30 to 70 °C

Power supply

6 to 20 VDC

Data logger compatibility

METER ZL6, EM50/60 series, Campbell Scientific, Infield 7


1.5 m; 8-pin plug M12; pigtail adapter available for connection with CSI dataloggers
3.5m; M12 stereo plug for METER data loggers


METER uses UV-resistant, durable materials for long-term field studies. Seals and screw connectors are watertight according to IP 68

T8 Tensiometer Manual


TensioLINK Guide