A data logger is an electronic device designed to record measurements at specific intervals. Measurements can include water temperature and water level, air temperature, humidity, current and voltage, variations in pressure, light intensity, soil moisture, rainfall, pulse signals, wind speed and direction, room occupancy and even the wetness of leaves.
Data loggers are generally a compact device powered by a battery. It consists of an internal microprocessor and a data storage facility, along with some form of data sensor. Size and design varies depending on the data being recorded: the data logger can be a single piece of equipment small enough to be carried by hand, or it can be a stand-alone unit with multiple channels and external sensors. These devices can be used in a number of settings that require data to be measured and recorded consistently. Most devices are able to operate for years at a time unattended.
Most modern data loggers are designed to interface with both personal computers and smartphones in their set-up, control, and analysis. More sophisticated models may include sensors that record input from GPS devices, as well as sensors for recording humidity, wind, heat, light and other elements.
How A Data Logger Is Used
A data logger comes with specific software for its graphing and analysis purposes. Depending on the application, the logger must be connected and configured according to which sensors are to be sampled and how the logger will be operated.
Once deployed in its selected location the data logger can record and store each time-stamped measurement. Once the desired monitoring period is complete, the data logger is then reconnected with the software in order to obtain the recorded data. Measurements may be displayed in graphs, which are useful for showing changes over time. Most software programs will also allow the user to view tabular data and export the recordings to a spreadsheet.
Types of Data Loggers
- Temperature data logger:Temperature indicators and recorders are important tools for supply chain maintenance. A temperature data logger monitors temperature throughout the shipping and handling stages of the chain, and provides alerts in the event of a temperature-related event. This allows action to be taken before product damage can occur. These types of data loggers are often used to monitor shipments in a cold supply chain industries, as well as in gathering temperature data from diverse field conditions.
- Wireless data logger: The ideal solution for real-time, continuous monitoring, wireless data loggers operate from any location from any web-based device. Like any data logger, it provides a configurable alarm system and instant access to real-time recorded data. A wireless data logger requires no additional hardware, which makes it the preferred choice for on-demand data maintenance. It’s one of the most flexible logging devices available, and can accommodate a variety of applications.
- Humidity data loggers: Along with temperature data loggers, humidity data loggers are often used in temperature-sensitive environments such as calibration rooms, warehouses, greenhouses, attics, basements and homes. These types of data loggers feature built-in sensors to measure environmental humidity levels and provide real-time alerts in the event of abnormalities.
- Pressure data logger: Pressure data loggers are used in a variety of settings to measure the pressure of gases or liquids. They can also be used for variables such as fluid and/or gas flow, water levels, altitude and speed. Depending on the environment, a pressure data logger may measure gage and absolute pressure, and/or bridge input for strain or load measurement. Some data loggers may also record data regarding tri-axial shock data using built-in accelerometers. Due to the nature of the environment, pressure data loggers are generally designed to withstand harsh and underwater conditions
- Vibration data logger: Also known as a shock data logger, a vibration data logger is a device that can measure and record shocks and vibrations over a period of time. Data is provided digitally, usually in the form of acceleration and time. The recordings are then able to be retrieved or transmitted for examination and evaluation. A vibration data logger generally consists sensors such as accelerometers, as well as a processor, storage media and power supply. The shock sensors are designed to measure impact as summary data or an entire waveform. They can also provide an indication of whether a threshold was breached.
- RTD data logger: A resistance temperature detector (RTD) data logger is a sensor that provides an indication of temperature. Most comprise of a length of wire made of platinum, nickel or copper. The wire is coiled around a glass or ceramic core and provides a highly accurate resistance/temperature relationship reading. RTD data loggers are a fragile piece of equipment and usually protected by probes.