Data Acquisition

Campbell Scientific dataloggers are extremely rugged measurement and control systems that combine the ability to deliver accurate, reliable measurements with on board data processing, data manipulation and the control of external devices. For example: open flood gates, operate pumps, trigger and samplers. Campbell Scientific equipment has a proven track record in all industries including meteorology, agriculture, water resources, air quality as well as the energy management and conservation, automotive, aviation and aerospace industries.

Each datalogger consists of a programmable measurement and control module housed inside a wiring panel/enclosure. Protected in a sealed, stainless steel canister, the measurement and control module provides sensor measurement, communication, data reduction, data/program storage and control functions. On board “smart” processing features include period minimums/averages/maximums, running averages and totals, wind vector calculation, histograms, polynomials (for discharge calculations) and a host of specialised scientific calculations and operations. Scan rates can be programmed from a few hours to 100,000 times per second, depending on the data logger model. All datalogger models are designed to accommodate a wide variety of industry standards, including:

• Single ended and differential analog channels for mV, mA, bridge, resistance and conductivity measurements
• Pulse input channels for counter (for example, a raingauge) and frequency measurements
• Digital I/O channels for pulse or frequency measurements and for RS232, SDI-12, MODBUS, etc digital communications protocols
• Switchable excitation channels for the excitation of external devices
• External switched power terminals for sensor power

All of our data acquisition systems are designed for automatic operation in remote locations. Systems may be powered by solar panels and batteries or battery backed mains power if this is available. A battery-backed clock assures accurate timekeeping while the multi-tasking operating system allows simultaneous communication and measurement functions.

Measurement and Control systems

Numerous communication options are possible, including:

• Direct connection (fixed RS232/USB/optical cable)
• Phone Telemetry (PSTN, CDMA, GSM, NextG, 3G)
• Radio Telemetry (Short Haul, VHF/UHF, Spread Spectrum)
• Satellite (Globalstar, Iridium, GOES, ARGOS, INMARSAT, etc)
• Network/Internet (Fixed and Wireless Ethernet, GPRS, 3G, Satellite).

The most common form of communication for monitoring networks is radio telemetry. Systems supplied by the Instrument Group include the Campbell/Maxon RF310 and the Trio DR/ER/MR450 and HR/KR900 series of radios. All are well proven in Australia and overseas and will provide remote, real time monitoring and control of every station, as well as allowing for remote data recovery, reprogramming, manual operation of external devices (such as pumps and valves) and changing of trigger points. Radio telemetry systems may be extendedto include more than 1000 field and repeater stations.

Software

A variety of software is available for data collection, processing and analysis. The Instrument Group generally supplies the Campbell Scientific range of software, including LoggerNet Datalogger Support Software, Real Time Monitoring & Control (RTMC) and RTMC Web Server software.

These software packages have been specifically written for the Campbell Scientific range of equipment and permits multiple users on the same computer network to access information from the remote monitoring stations.

LoggerNet software is installed on the computer that is to act as the radio network base station. The base station is set to poll each field station as described above. Information and data from each field station may be displayed in a number of ways.

Features of this software:

• The ability to program, monitor and control all stations, either directly or remotely, using a field computer or the base station computer (via the radio network)
• It provides digital, tabular and graphical display of station operation, and the importation of graphics to customise a screen
• The ability to collect data on-demand or automatically, perform some processing of data files and export data to third party analysis packages

Data from multiple stations can be combined in one display. Complex displays can be organised on multi tabbed displays and it is server based, permitting access of the system by more than one user.