Delta-T Devices Ltd.

- Model PR2 - Soil Moisture Profile Probe

From

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, or connect the PR2 to a data logger (GP2 or DL6) and leave the system to record soil moisture changes over time.

  • Soil moisture content profiles down to 1m
  • Dual purpose – installed and portable
  • Uses access tubes for easy probe insertion and removal
  • SDI-12 interface option available
  • Highly reliable field-proven instrument
  • Soil moisture content – not just trends
  • Out of the box solution – supplied with calibrations for common soil types
  • Portable meter option for multi-site measurement

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

HH2 Meter

The HH2 is a versatile readout unit that provides an easy and convenient way to display and store readings from Profile Probes. With the HH2 and PR2 combination, a probe can be moved from access tube to access tube, enabling large amounts of soil moisture data to be collected at multiple sites.

Data Logging

  • Profile Probes are available with analogue or SDI-12 outputs.
  • For the analogue version, order PR2/4 or PR2/6.
  • For the SDI-12 interface version, order PR2/4-SDI-12 or PR2/6-SDI-12.
  • Please note that analogue and SDI‐12 probes cannot be mixed on the same cable system

Loggers for analogue Profile Probes

  • Delta-T offers a choice of two data suitable data loggers. Both have dedicated PR2 Profile Probe input channels and connectors:
  • The DL6 Data Logger can log one PR2/6 or one PR2/4 Profile Probe
  • The GP2 Data Logger can log up to two PR2/6s or three PR2/4s

Loggers for SDI-12 Profile Probes

The PR2 SDI‐12 is ideally matched to the SDI‐12 enabled GP2 Data Logger. Many SDI-12 Profile Probes can be connected to a single GP2 (actual number depends on cable length, power, and other considerations).

Image

Augering and Extraction Kits – for optimal Access Tube installation

Profile Probes are used within access tubes inserted into augered holes in the soil – correct installation is vital for accurate measurement of soil moisture profiles. The goal of installation is to produce optimal contact between the soil and the wall of the access tube. The augered holes should be straight, smooth sided and the correct diameter.

Delta-T augering kits help you achieve the best possible access tube installation in virtually any soil.

  • 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