Delta-T Devices Ltd.

- Model GP2 - Advanced Data Logger and Controller


The GP2 is a powerful 12 channel data logger that is easy to use, versatile, rugged and reliable. It can log most sensor types and accepts voltage, resistance, current, potentiometer, bridge, counter, frequency, and digital state inputs. DeltaLINK software helps the user set up logging sequences and provides control over reading frequency, sensor type, thresholds, units and much more. All Delta-T sensors can be selected from a menu.

  • Powerful and rugged field data logger
  • 12 differential (or 24 single ended) channels
  • ideal for demanding research applications
  • Free use of DeltaLINK-Cloud data sharing service

Power and flexibility

  • The GP2 Data Logger features advanced controller functionality, and sophisticated programs can be easily created via a simple scripting editor.
  • As the user's needs change, the GP2 can adapt. Optional lids are available with additional cable entry points, dedicated Profile Probe inputs, or with wider diameter cable entry points.

Building systems with the GP2 Data Logger
The GP2 is the ideal data logger for field work, with applications ranging from agronomy, meteorology and hydrology to eco-physiology and soil science. We can supply complete systems including sensors, enclosures, solar power and communications options.

The GP2 Data Logger is compatible with all Delta-T sensors. For the Delta-T WET Sensor there is a dedicated input channel and for the PR2 Profile Probe there is an optional dedicated lid.

Delta-T has decades of experience of instrumentation for environmental research and can advise on all aspects of system specification.

The GP2 Data Logger can log most sensor types and accepts voltage, resistance, current, potentiometer, counter, frequency, and digital state inputs.

The GP2's analog inputs can be fully customised. Each channel can have its own input type and recording parameters. DeltaLINK software gives the user control over reading frequency, thresholds and units, and provides statistical recording options for Average, Minimum, Maximum, Standard Deviation and more. Specialised wind options are available including wind rose, gusts and wind averaging.

Users can add their own custom sensor types to the sensor library, exploiting the GP2's detailed configuration options. The GP2 provides 4 input ranges down to microvolt resolution with adaptive auto-ranging, excellent analog accuracy, and configurable sensor excitation - enabling it to support nearly all analog sensors.

Calculations based on the measurements from several input channels can be recorded and displayed as additional virtual channels (calculated measurements).

Simple point and click software makes it easy to configure channel set-up and recording intervals. The menus that support the advanced customisation options can be displayed or hidden as required.

Sensor connections are laid out logically with clear, easy-to-follow diagrams and notes.
The GP2's weatherproof case, battery power and convenient accessories make it very easy to install in the field - often without the need for a secondary enclosure.

This unique software feature allows logging programs to be tested before real-world activation. For applications involving weather data, irrigation or soil moisture recording, the environmental variables can be changed to test how the program responds. Years of logging time can be simulated in just a few minutes.

Storage, communications and power
4 Mbytes of FLASH memory enable storage of 2.5 million readings (typical). Data can be collected by a laptop locally via USB/RS232 or remotely using the GPRS modem options.

The GP2 has 6 alkaline AA internal batteries as standard. An optional mains power adapter is available (type GP2-PSU). Up to 7 GP2s can share power and communications using an M12 cabling network. GP1 Data Loggers can be integrated into such a network via an adapter cable.


The GP2 Data Logger has been upgraded to support SDI-12 inputs. All new GP2s come with SDI-12 as standard - and GP2s supplied before March 2016 can be easily updated via a software download.

Key features:

  • Huge additional input capacity for SDI-12 sensors
  • Existing analogue and digital channels fully available
  • Highly flexible logger + sensor networks

The GP2 Data Logger has a wide range of environmental, agricultural and industrial applications: Horticulture and Irrigation , Soil Science,  Plant Physiology, Agronomy Climate Research and Meteorology, Agriculture, Turf and Gardens, Amenity Landscaping, Ecology, Field Trials, Eco-Physiology.

  • Input connections:
    • 12 differential (or 24 single-ended) analog inputs con?gurable as: Voltage, Resistance (12 3-wire or24 2-wire), Bridge (12), Potentiometer (12)
    • 4 digital inputs as: Counters, (2 fast + 2 slow), Frequency, Digital state
    • 1 Delta-T WET sensor channel Unlimited virtual channels
  • Control outputs: 2 relay outputs expandable to 6 (1A)
  • Readings stored: 2.5 Million
  • Recording rate: 1 second to 24 hours
  • Configuration: DeltaLINK
  • Communication options: USB/RS232 or modem
  • Sensor excitation: Calibrated 3V reference, +5V and+12V regulated, or 5 to 10.5V (battery or external power), user selectable.
  • Power: 6 AA alkaline batteries or external power 10-15V DC
  • Battery life (dependent on usage): ~ 300K readings
  • Enclosure rating: IP65
  • Temperature range: -20 to +60°C
  • Display
  • Size: 225 x 185 x 75mm
  • Typical applications: Demanding research projects
  • Environmental monitoring
  • PID control applications

Sensor compatibility (maximum number of sensors that could be connected [2]

  • ML3: (6) with temp / (12) without temp
  • SM150T: (6) with temp / (12) without temp
  • PR2: (2 PR2/6 with expansion lid) (3 PR2/4 with expansion lid)
  • PR2 SDI-12: (50)
  • WET Sensor: (1)
  • EQ3: 6 with temp / 12 without temp
  • Temperature: (12)
  • Tensiometers: (12)
  • Counters or Events: (4) 2 fast 2 slow
  • Relay Output: (2) expandable to (6)

 [2] With appropriate expansion cards and power supply arrangements