Data loggers and related measuring devices record a wide array of important information. Types of data that can be captured in this fashion include, but are not limited to, temperature, humidity, voltage, vibrations, pressure and pH levels; the specific types of physical phenomena measured depends on the design and sensor of the particular device. Given the broad diversity of uses for data loggers, it is no surprise that these devices satisfy application needs in a number of industries, such as automotive, food processing, medical and everything in between. Loggers are capable of measuring various physical phenomena with extreme precision—but only if they have been properly maintained. One major aspect of data logger upkeep is regular calibration; this is a simple yet highly important procedure that helps these devices deliver accurate functionality. Let's take a closer look at the issue.
Data logger sensors can become less accurate with the passage of time, due to environmental stressors, repeated use, or the simple aging of its components. Without maintenance, eventually the logger can no longer be accurately relied upon to measure data within an acceptable range of accuracy. For many applications, the required range of accuracy is extremely narrow—for example, some devices must be able to measure temperatures with an accuracy of <0.1Â° C. When a device has fallen outside this range, it is said to be "out of tolerance" (OOT). Using an OOT device can cause serious problems in industrial environments where precise measurements are vital. The answer to this problem is regular maintenance to ensure that data loggers have been calibrated correctly and on schedule.
A Quick Overview of Calibration
In essence, calibration involves measuring a device against a specific standard. This can involve comparing it with another device whose accuracy has been verified, or testing its ability to measure physical phenomena whose parameters have been previously substantiated. The inspector adjusts and/or upgrades the device until it can record measurements within an acceptable range, which varies according to the particular performance demands of the unit. It's worth pointing out that this service should be performed only by a trained specialist. There are a number of professional services that not only provide expert calibration, but also provide an official NIST Traceable Certificate (National Institute of Standards and Technology) to guarantee that the process has been carried out according to verifiable standards.
Additional Maintenance Tasks
When data loggers are sent to the manufacturer for calibration it is also good practice to inspect the device for any other regular maintenance needs such as battery or O-ring replacement. These high precision instruments are designed to be durable in the field and deliver accurate results. Regular maintenance routines will keep the device performing as expected while extending the life of the logger.
What Is a Calibration Interval?
How often should a device undergo calibration? As you might expect, there is no simple answer. It's most common for devices to require calibration service once per year, but depending upon the application details and the device being used, more frequent calibrations may be required to ensure accurate results. This period of time between calibrations is called a calibration interval. As always, it's best to follow manufacturer recommendations to ensure that data loggers undergo calibration at appropriate intervals.