Data loggers are data acquisition tools used to monitor systems and processes by recording data points over a timed interval. A data logger is the perfect device for those situations where it is prudent or necessary to document conditions, verify that systems are working properly, or to comply with regulatory requirements. Since data loggers produce a permanent archive of conditions within a digital memory, the data can be stored indefinitely and used for future reference.

Being compact and self-contained, data loggers excel at recording data from temperature, flow, pressure, voltage, current, resistance, and other sensors over a long period of time in in unattended or remote locations, at times in harsh conditions. The nature of their use requires data loggers be extremely reliable. Data loggers can be used for a wide range of applications; from documenting the historical data for batch processes to charting temperature and humidity readings in a museum display. Most are easily customized for a particular application though they may require specific modules or sensors depending upon the task.

Data loggers are designed to accept input from either internal or external sensors. Certain loggers are able to handle multiple sensors. Sensors can be either active or passive devices. Passive sensors, like thermocouples, do not require an outside power supply to generate a signal. Active sensors, on the other hand, do require a power supply to generate a signal. There are numerous ways to power the sensors depending upon the application. The control membrane switch  can be customized according to the application also.