- Overview
- Specification
- Accessories
- Product Resources How to Buy


Testimonials
I’ve now had the opportunity to thoroughly test the WET150 in the field, and I’m pleased to say that it has been very effective at recording percentage moisture in the wet calcareous‐fed mire environment.
Knowing the topography of the site as I do, I can say that the data visuals we have created using the WET150’s output are really exciting." Dr David Oatway,
Ecologist and Research Consultant at Ketmar
- Lower cost research-grade soil sensor kit for portable use
- Instant measurements of moisture, EC, and temperature
- Comes complete with readout meter and case
The WET150 Kit is a portable and rugged solution for researchers who need to assess moisture and salinity conditions in soils and substrates.
The Kit makes fast soil/substrate measurements of three crucial variables that influence plant growth: moisture content, temperature*, and electrical conductivity (EC) – a strong indicator of the general nutrient level.
*We recommend that the WET150 is used as a portable hand held sensor only in well-equilibrated environments where the air temperature doesn’t differ significantly from the soil/substrate temperature.
Kit Contents
The Kit comprises a WET150 Sensor, a WET150 hand-held readout meter, and a carry case. When correctly connected and tightened, the kit’s cables and connectors are completely watertight. The handheld WET150 Meter displays volumetric water content as % volume and EC in milliSiemens/metre.
The WET150 Meter is a lightweight and easy to use readout-only device (no data recording or other complications). Operation of the kit is straightforward – the user inserts the WET150 into the soil or substrate and presses the “Read” button on the meter to take and display the measurement.
The WET150 Sensor comes complete with calibrations for mineral and organic soils plus coir, peat, and mineral wool substrates soils.
Research Applications
The WET150 Kit can be used solely for precise reliable readings of soil/substrate water content. However, the inclusion of electrical conductivity (pore water conductivity ECp) measurement makes it particularly well suited to horticultural research in the areas of fertigation, precision irrigation, and soil salination monitoring.
WET150 Kit use in Commercial Horticulture
Details on the WET150 Sensor as a standalone device
Video – The Wet150 Sensor’s use in research and horticulture
Specification
WET150 Sensor
VOLUMETRIC WATER CONTENT | PORE WATER CONDUCTIVITY (ECp) | PERMITTIVITY | BULK CONDUCTIVITY (ECb) | TEMPERATURE | |
ACCURACY |
± 0.03 m3.m-3 (3%)
|
See graph below this table
|
± (3% of reading + 0.8 ε’)
1 → 40
|
± (10mS.m-1 + 6%)
|
± 0.5°C
(0°C to +40°C range)
± 0.7°C
(-20°C to +60°C range)
|
± 5% of reading
40 → 80
| |||||
RANGE |
Full range:
0 to 1.0 m3.m-3
|
See graph below this table
|
for ECp ≤ 800 mS.m-1
1 → 40
|
from 0 to 1200 mS.m-1
|
Full range:
-20°C to +60°C
|
Accurate range:
0.05 to 1.0 m3.m-3
ECb 0 to 500 mS.m-1
|
for ECp ≤ 500 mS.m-1
40 → 80
|
Accurate range:
0°C to +40°C
| |||
OUTPUT |
SDI-12 protocol 1.3 (www.sdi-12.org) Providing water content, pore water conductivity, and temperature - together with base readings of permittivity and bulk conductivity. Outputs are exceptionally configurable. | ||||
POWER REQUIREMENT |
Operating voltage: 6 to 20 Volts Current consumption (typical values powered from 12 Volts): Active sensing: 22 mA average over 12 ms (average includes short peaks at 45 mA) Active results computation: 2 mA over 188 ms Idle: <0.5mA | ||||
ENVIRONMENTAL |
IP68, - 20 to + 60°C | ||||
SAMPLE VOLUME |
~55 x 70 mm diameter | ||||
Sample volume is weighted towards soil immediately surrounding the rods | |||||
DIMENSIONS |
Overall: 143 x 40 mm dia Rods: 51 mm x 2.5 mm dia | ||||
WEIGHT |
Weight: 77g (excl. cable) | ||||
SENSOR CALIBRATIONS |
Individual sensors are interchangeable Recalibration advised every 5 years (depending on use) | ||||
SOIL CALIBRATIONS |
The WET150 Sensor comes complete with calibrations for mineral and organic soils plus coir, peat, and mineral wool substrates |

Notes: [1] The WET150 has been carefully optimised to provide accurate readings in soils and substrates - readings taken in water or air may not meet the full specification. [2] The ECp contour map is based on measurements from 30 sensors at 20°C in NPL* traceable media. Calculated ECp readings are derived from the Hillhorst equation, using the generalised “mineral” soil calibration and the default soil parameter = 4.1 * NPL is the UK's National Metrology Institute, developing and maintaining the national primary measurement standards.
WET150 Meter
INPUT CONNECTIONS | 1 WET150 multi-parameter water content sensor |
CONFIGURATION | By keypad |
SENSOR EXCITATION | Via SDI-12 |
POWER | 2 x AA alkaline batteries |
BATTERY LIFE | > 2400 readings |
ENCLOSURE RATING | IP65 |
TEMPERATURE RANGE | 0 to +40°C |
DISPLAY | 2 line x 16 character |
SIZE | 130 x 66 x 25 |
Accessories
Hardware
Main components and software
Mountings and enclosures
Installation accessories
Cables and networks
Remote communications
Spares and consumables
Power options
Other
Product Resources
Case Studies
- Using the WET150 in Teesdale plant species recovery research 6 MB
Dr David Oatway makes extensive used of the WET150 Soil Sensor in urgent plant species recovery research (Upper Teesdale, North of England - SSI).
DownloadFilename: Teesdale_WET150_Case_Study_ver_1 - Seven brief Delta-T Devices soil moisture sensor case studiesDownloadFilename: →
Videos
Manuals
- WET150 Kit Quick Start Guide 608 KBDownloadFilename: WET150_Kit_Quick_Start_Guide_v3
- WET150 Sensor User Manual 2 MBDownloadFilename: WET150-UM-01-2.0 (WET150_User_Manual_v2.0)
- WET150 Sensor Quick Start Guide 646 KBDownloadFilename: WET150_Quick_Start_Guide_v.3
- WET150 SDI-12 Programmer Guide 438 KBDownloadFilename: WET150 SDI-12 programmer guide v2