What is a Data Logger ?

A data logger is a solid state device used to measure and record analogue and / or digital inputs from sensors or other instruments. Typically these sensors or other instruments will themselves be measuring environmental or process parameters such as temperature, humidity, pressure, flow, level, wind speed, wind direction, and many other physical properties.

A data logger is a stand alone recording device. It does not need a PC to store it’s data. There are many types of data logger. However they fall into two broad categories.

1) Small compact battery powered data logger for use in remote locations or in application where weight and space available is critical

2) Large multi channel data logger, usually mains powered to store large amounts of data from many external sensors and inputs.

Data logger design has improved exponentially over the last few years. A typical small data logger for single channel temperature measurement will be no larger than a matchbox, and can store up to 32,000 temperature readings. Utilising flash memory some 4 and 8 channel data logger types are still small enough to fit in your pocket, with battery life of up to 2 years.

Most types of data logger come with custom software to download data to a PC, show the results in graph and table format, and export data to MS Excel and other applications. The proprietary software is also used to program the data logger for sample rate, and logging duration. Data is usually downloaded directly from the data logger to the PC. However with many types of data logger data download can also be achieved remotely using Ethernet, low power radio, GSM, GPRS or telephone lines. Some data logger models also publish their data direct to websites.

Due to it’s versatility in measurement applications the data logger has become an indispensable tool for academic and medical research, biologists, physicists, process engineers, civil engineers, electrical engineers and environmental scientists. A wide range of data logger types are used across a whole spectrum of industries, including power generation, oil and gas exploration, general manufacturing, civil construction, aerospace, horticultural and medical science.

Omni Instruments has been actively involved in the data logger market for over 10 years and has supplied all data logger types for a vast range of applications. They include:

Temperature data logger – for use in offices, factories and hospitals
Temperature and humidity data logger for measurement in museums and warehouses
Temperature, rainfall, wind speed and direction, solar radiation and barometric pressure data logger for measurement in remote weather stations
Multiple input data logger units for vibration, orientation and movement measurement in robots and remotely controlled vehicles
Process data logger units for pressure, flow and level measurement in factories and plants
Vibration data logger for goods in transit

In short a data logger in many applications is a far more effective means of recording measurements and activity than a man with a clip board or traditional recording instruments such as chart recorders.

Jim Furness is CEO of Omniinstruments Ltd, specialists in data loggers and other instrumentation solutions