- Overview
- Specification
- Accessories
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Testimonials
Scientific Coordinator at the Jena Experiment, Germany
(DFG-funded Research Unit)
- Portable, accurate soil moisture profiles to 1m depth
- Portable meter option for multi-site measurement
- Uses access tubes for easy probe insertion and removal
No other soil moisture probe system enables you to monitor your soil water profiles with such ease and flexibility. Install an access tube into the soil, insert the PR2 Profile Probe and press the HH2 [Read] button to display an instantaneous reading. Alternatively, connect the PR2 to a data logger (GP2 or DL6) and leave the system to record soil moisture changes over time.
Video – Introduction to PR2 Profile Probe
The PR2 Profile Probe is built around patented sensing technology which provides excellent performance in all soil types, with minimal influence from either salinity or temperature. The PR2/4 model measures soil moisture at 4 depths down to 40 cm – the PR2/6 measures at 6 depths down to 100 cm.
The PR2 Profile Probe access tube requires an installation hole 27 mm in diameter, allowing easy installation and minimal soil disturbance. Access tubes are manufactured to strict tolerances and are exceptionally strong and durable in the soil. Correct installation is essential and we recommend the use of our specially designed augering equipment.
The PR2 Profile Probe is available in two sizes to measure to a depth of 40 cm or 100 cm.
The PR2/4 has sensing elements at 10/20/30/40 cm
The PR2/6 has sensing elements at 10/20/30/40/60 and 100 cm
Complete Auger Kit
Access tube installation is vital.
Click here for information about our augering equipment
Further information
The PR2 Profile Probe is also well suited to research applications in horticulture, hydrology, crop science, and water use efficiency. For further details click here.
Specification
For Analogue PR2 and SDI-12 PR2
| Measurement | Volumetric water content |
| Accuracy | ± 0.04 m3.m-3 (4%) With soil-specific calibration |
| Soil moisture measurement range | Full accuracy over: 0 to 0.4 m3.m-3 |
| Full range : 0 to 1.0 m3.m-3 | |
| Salinity range | 50 to 400 mS.m-1 |
| Salinity errors included in calibration | |
| Temperature range | Full accuracy over: 0 to 40°C |
| Output | (ANALOGUE) 0 to 1.0 V differential PR2/6: x6 outputs, PR2/4: x4 |
| (SDI-12) Digital | |
| Power requirement | (ANALOGUE) 5.5-15 V, PR2/6: ~120 mA for 1s PR2/4: ~80 mA for 1s __________________________ Minimum 7.5 V with 100 m cable |
| (SDI-12) Power consumption <60 mA at 12 V DC Sleep current <2 mA at 12 V DC | |
| Environmental | IP67 (when installed in access tube) |
| Sample volume | -95% sensitivity within a cylinder of diameter 200mm |
| Sample volume is weighted towards soil immediately surrounding the rods | |
| Dimensions and weight | PR2/6: length 1350 mm PR2/4: length 750 mm Both: 25.4 mm diameter PR2/6: weight 1.2 kg PR2/4: weight 0.8 kg |
| Sensor calibrations | Individual sensors are interchangeable Recalibration advised every 3 years (depending on use) |
| Soil calibrations | Generalised Mineral and Organic soil calibrations are supplied |
Accessories
Hardware
Main components and software
Mountings and enclosures
Installation accessories
Cables and networks
Remote communications
Spares and consumables
Power options
Other
Product Resources
Data Sheets
- PR2 Profile Probe SDI-12 Data Sheet 1 MB
Filename: PR2_SDI-12_v.2 - Soil Moisture Measurement Catalogue 14 MB
Filename: Soil_Moisture_Measurement_Catalogue_ver_5
Case Studies
- PR2 Futmon Case Study 638 KBDownloadFilename: pr2_futmon_case_study_ver_1
- The Jena Experiment - extensive use of PR2 Profile Probe in major ecosystem research project 4 MB
The Jena Experiment is a long‐term biodiversity focused research project funded by the German Research Foundation (DFG). The PR2 Profile Probe has been an important part of the Jena Experiment's sensor network for nearly the entirety of the long running project.
DownloadFilename: The_Jena_Project_case study_PR2_Profile_Probe_08.02.21 - Seven brief Delta-T Devices soil moisture sensor case studiesDownloadFilename: →
- Cranfield University use the PR2 to explore how tillage affects water transport through the soil profile 2 MBDownloadFilename: PR2_Cranfield_tillage_research_case_study_version_1
Videos
Manuals
- PR2 Profile Probe User Manual ver 5.0 2 MBDownloadFilename: PR2_user_manual_version_5.0
- PR2 Profile Probe Quick Start Guide 3 MB
PR2 Profile Probe Quick Start Guide v2.0, 2008
DownloadFilename: pr2-profile-probe-qsg
Quick Start Guide. See also PR2 UM and PR2 Augering UM and Kits QSG. - PR2 SDI-12 User Manual 2 MBDownloadFilename: pr2_sdi-12-_user_manual_version_4_1
- PR2 Augering User Manual 3 MB
User Manual for Augering Kits for Profile Probe access tubes. The manual describes how to install short and long access tubes in most soils using the Delta-T range of augering tools and equipment. The information contains important and essential guidance on creating good installations, which applies to both PR2 and PR1 Profile Probes.
DownloadFilename: aug-augering-user-manual-v2-0 - PR2 Augering Quick Start Guide 4 MB
Augering Quick Start Guide v1.0.pdf
DownloadFilename: aug-augering-quick-start-guide-v1-0
QSG forProfile Probe access tube Augering Kits. Briefly describes how to install short and long access tubes in most soils using the Delta-T range of augering tools and equipment. - Augering Health and Safety Sheet v1.0 47 KBDownloadFilename: augering-health-and-safety-sheet-v1-0
FAQs
- Setting up an M12 cable network to ensure a waterproof and secure connection.
Question
What is the best practice for setting up a M12 cable network to ensure a waterproof and secure connection..
Answer
It applies to:
GP2 for SDI-12 and logger networks.
Celora for SDI-12 networks.
All sensors with M12 connector cables.Examples of SDI-12 network and GP2 logger networks:
DO
When connecting multiple cables and T-piece together, it is essential that any M12 connector is tightened sufficiently:
• Ensure internal connector O-ring and opposite sealing face are free from dirt.
• Tighten the connector thumbscrews as much as you can by hand or use a torque driver set to 1Nm to be sure. See video:We recommend the Weidmuller “1900021000” torque driver:
• This will save lots of painstaking troubleshooting hours if you do have a loose connection and give you piece of mind that all connectors are correctly tightened.
• Untightened connectors can come undone and let water into the cable network which can damage wire cores and cause erroneous readings.
Connect in the office first and then transfer the network to the field. This way, you’re not trying to do it in unpleasant weather and the time pressures are off.
DON’T
Use duct tape. This will hold water against the connector. If tightened correctly, the connector will seal and hold. - How do I use the augering equipment and take measurements with a PR2 Profile Probe? – Video Guide
Question
How do I use the augering equipment and take measurements with a PR2 Profile Probe? - Video Guide
Answer
We would always recommend reading through the PR2 profile probe user manual and our augering user manual for the most up to date information on this topic. In addition, we have released this video to help:
- How can I create soil-specific calibrations for my PR2 Profile Probe?
Question
How can I create soil-specific calibrations for my PR2 Profile Probe?
Answer
The Profile Probe User Manual recommends that you use a Theta Probe (ML2x or ML2) to do a two-point soil-specific calibration.
You need to measure the moisture content of a wet sample of your soil, using the Theta Probe, and then oven-dry the sample and measure its water content once again.
The process is fully described in the Theta Probe User Manual and is also available in a detailed application note available from Delta-T. This should enable you to decide if the possible gain in accuracy is worth the additional effort of the calibration.
If you do not possess a Theta Probe, please contact your distributor or Delta-T for advice. The User Manual is available by email in electronic Acrobat pdf file format (and may be available for download from the Delta-T website).
Regulatory Information
- PR2 Profile Probe EC Declaration of Conformity 34 KBDownloadFilename: pr2-profile-probe-ec-declaration-of-conformity