What does a data logger do?

Data logger, also called datalogger or data recorder, is an electronic device used to record, collect, and store data from some type of sensor. It has its own local memory to store these data and includes a time stamp. There are many types of data loggers with different features, functions, and used for different measurements. Dataloggers are usually battery-operated and come either included as a part of a measurement device, or they can come separately with input option to be connected to the measuring device.

Data logger is basically your personal log to store all your data and measured values. Therefore, data logger.

What do I need to know to operate a data logger?

Usually, a data logger is composed of a microprocessor, an internal memory for data storage (a memory card or flash disk), and a sensor which collects data. Data Loggers are not programmed but configured (or equipped with a software). That means that you don´t need to be a programmer to operate a data logger. Usually, there is a very user-friendly interface with display, buttons, and possibly input holes. So, all you need to know to operate a regular data logger is pushing buttons.

How is the data stored and how can I get it?

The data collected by the data logger is usually stored on a flash disk or memory card. You can easily access the data by opening the files on your PC. More advanced data loggers offer the feature of sending the data via Ethernet, Wi-Fi, etc. The selection of the product will depend on your setup.

The data formats have not been standardised, but there is a prevalent recent tendency to store the data either as XML, JSON, or YAML formats. To extract the data, you can either print it, connect the device to a PC and extract the data, or transmit the data wirelessly to any connected device.

Wi-Fi connected data loggers

Usually, data loggers feature USB ports, but a very popular feature is the network-connectivity. With this option, you can store your data in a cloud storage, remotely access the device, share data via email, connect more data loggers to each other, or set up alarm notifications, and many more functions.

How does a data logger differ from data acquisition systems?

Data acquisition systems are used to collect data much faster that data loggers and therefore they need a network or PC connection for storage of the huge amounts of data. Also, they are usually much more expensive than data loggers.

How can a data logger record data?

The duration of the recording usually depends on the memory capacity, which will be different according to the specifications of each type of product. Also, the duration depends on the desired sample rate – if you want to find out the precise duration, just divide the memory capacity (or the number of the samples that the device is capable to record) by the sample rate. The higher the sample rate, the smaller will be the duration of the memory. Some data loggers can have their capacity extended by replacing the SD or memory card for another card with bigger memory.

How accurate is a data logger?

The accuracy will differ, each type and product have their own specifications. Usually, the accuracy ranges between 1-2% to 0.01%.

Input types

What type of information can data loggers store? Some data loggers are designed to store only one type of data, other are multifunctional and can store multiple data types. According to the type of the device, it can store one or more of these values (Some of them can even accept all the types of the following data!):

• Pressure
  Usually the pressure of gases and liquids or atmospheric and water pressure.
• Temperature
  Data of extremely high or low temperature as well as liquid temperature can be stored.
• Humidity
  Relative humidity, dew point, water vapor concentration can be stored in standard or metric units.
• Voltage
  The device is adaptable to any voltage measurement, including pressure to torque and load to force.
• Current
  AC and DC data loggers are often used for monitoring building equipment.

What are data loggers used to?
Like we just listed, data loggers can monitor temperature, humidity, carbon dioxide, pH, pressure, voltage, current, or pulse – that means they can be useful for many various types of applications. For example, they can verify temperature and humidity levels of storage and transportation facilities. You can use them to provide building maintenance information on heating, ventilation, and air conditioning operations to assist with energy conversation. Also, data loggers can monitor growing conditions in the agricultural industry, vaccine storage in a medical facility, or the temperature of food. However, there are many other types of use for data loggers.

Types of data loggers

Most popular types of data loggers include:

• Temperature data logger
• Voltage data logger
• Current data logger
• Power data logger
• Electrical data logger
• Vibration data logger
• Shock data logger
• Strain data logger
• GPS data logger

You will choose your data logger according to which measurements you want to perform. To start with, this basic data logger is wired into a temperature and relative humidity meter: https://measuritec.com/products/amprobe-tr300-temperature-and-relative-humidity-data-logger .

You can also buy a data logger together with a classical multimeter here https://measuritec.com/products/fluke-289-fvf-eur-true-rms-industrial-logging-dmm-w-trendcapture-fvf-s-w-euro or another type of this product here https://measuritec.com/products/benning-mm-10-1-hand-multimeter-digital-data-logger-cat-iv-600v-display-counts-6000 .

For yet another type of measurements, there are data loggers with thermometer functions like this product https://measuritec.com/products/peaktech-p-4955-dual-laser-ir-thermometer-with-datalogger .

If you want to perform wind speed measurement, check out this hot wire anemometer with data logger – the device features data storage of an SD card in Excel format: https://measuritec.com/products/extech-sdl350-hot-wire-thermo-anemometer-data-logger .

Last but not least, there are multifunctional devices like this product https://measuritec.com/products/xds3202a-digital-oscilloscope-data-logger-multimeter-signal-generator-functions-like-n-in-1-200-mhz-and-2gs-s, which is a 3-in-one device – it features an oscilloscope, data logger and multimeter functions.

To end with, this professional tool https://measuritec.com/products/32-channel-industrial-thermocouple-thermometer-data-logger-industrial-temperature-data-logger-at4532 features thermocouple, thermometer and data logger function.

If you want to purchase some additional devices to your data logger, check out for example this automatic timer for data logger: https://measuritec.com/products/gowe-automatischer-timer-fur-datalogger-digitales-thermometer-feuchtigkeitsmesser-messgerat-fur-dataloger-temperaturmessgerat?variant=39359669764290. It can be used with data loggers, digital thermometers, humidity meters, or data logging temperature meters.

When choosing a data logger, make sure the device features all the options that you need for your measurement and data storage.

What is the future of data loggers?

The usage of data loggers has been changing a lot. In the past, data loggers were rather used as a stand-alone device for data collection, while recently it has become more popular to connect data loggers wirelessly to use them also for alarming of events, automatic data reports, remote control, etc. Data loggers are also being connected to web pages, emails, and send their daily data databases automatically to the user. So, we can see that the role of the device has been shifting a lot. How the data loggers will be used in the near future, only time will show.