Data Loggers
Data Logger or data recorder is an electronic device that records data over time or in relation to location either with a built in instrument or sensor or via external instruments and sensors. Increasingly, but not entirely, they are based on a digital processor or computer. They generally are small, battery powered, portable, and equipped with a microprocessor, internal memory for data storage, and sensors. Some data loggers interface with a personal computer and utilize software to activate the data logger and view and analyze the collected data, while others have a local interface device and can be used as a stand-alone device.
Technically speaking, a data logger is any device that can be used to store data. This includes many data acquisition devices such as plug-in boards or serial communication systems which use a computer as a real time data recording system. However, most instrument manufacturers consider a data logger a stand alone device that can read various types of electrical signals and store the data in internal memory for later download to a computer.
The advantage of data loggers is that they can operate independently of a computer, unlike many other types of data acquisition devices. Data loggers are available in various shapes and sizes. The range includes simple economical single channel fixed function loggers to more powerful programmable devices capable of handling hundreds of inputs. Data loggers vary between general purpose types for a range of measurement applications to very specific devices for measuring in one environment or application type only. It is common for general purpose types to be programmable; however, many remain as static machines with only a limited number or no changeable parameters. Electronic data loggers have replaced chart recorder in many applications. One of the primary benefits of using data loggers is the ability to automatically collect data on a 24-hour basis. Upon activation, data loggers are typically deployed and left unattended to measure and record information for the duration of the monitoring period. This allows for a comprehensive, accurate picture of the environmental conditions being monitored, such as air temperature and relative humidity. The cost of data loggers has been declining over the years as technology improves and costs are reduced. Simple single channel data loggers cost as little as $25. More complicated loggers may costs hundreds or thousands of dollars.
Applications
- Weather station recording
- Hydrographic recording
- Soil moisture level recording
- Gas pressure recording
- Offshore buoys for recording a variety of environmental conditions
- Road traffic counting
- Measure temperatures ,humidity, etc. of perishables during shipments: Cold chain
- Process monitoring for maintenance and trouble shooting applications
- Process monitoring to verify warranty conditions
- Wildlife research with pop-up archival tags
- Measure vibration and handling shock environment of distribution packaging
- Tank level monitoring
- Deformation monitoring of any object with geodetic or geotechnical sensors controlled by an automatic deformation monitoring system.
- Environmental monitoring
- Vehicle Testing
- Motor Racing
- Monitoring of relay status in railway signalling
- For science education enabling 'measurement', 'scientific investigation' and an appreciation of 'change'
- Record trend data at regular intervals in veterinary vital signs monitoring
- Load profile recording for energy consumption management
- Temperature, Humidity and Power use for Heating and Air conditioning efficiency studies
- Water level monitoring for groundwater studies
- Digital electronic bus sniffer for debug and validation
Future directions
Data Loggers are changing more rapidly now than ever before. The original model of a stand alone data logger is changing to one of a device that collects data but also has access to wireless communications for alarming of events, automatic reporting of data and remote control. Data loggers are beginning to serve web pages for current readings, e-mail their alarms and FTP their daily results into databases or direct to the users.