Every month, Control's editors take a specific product area, collect all the latest, significant tools we can find, and present them here to make your job easier. If you know of any tools and resources we didn't include, send them to email@example.com, and we'll add them to the website.
The most common and frequently measured variable is temperature. But, this "Calibrating Temperature Instruments" whitepaper reports that every temperature measurement is different, which makes the temperature calibration process slow and expensive. While standards determine accuracy that manufacturers must comply with, they don't determine the permanency of accuracy. So, users must be sure to verify the permanency of accuracy. If temperature is a significant measurable variable from the point of view of the process, it's necessary to calibrate the instrument and temperature sensor. This is a free download.
CALIBRATING SMART TRANSMITTERS
This whitepaper outlines practices for calibrating smart transmitters. It covers subjects, including range setter, current trim, sensor trim, device integration, getting better calibration results and pre-commissioning calibration. It is free and no registration is required.
Across various industries, the performance of a flow measurement device is ultimately dependent on the proper functioning of its sensors or other signal-producing elements, which have an active relationship with the flowing fluid. In order to be confident that a meter is accurately measuring the flow volume or mass, it must be recalibrated on a periodic basis. This whitepaper presents various choices for building a successful recalibration program. It's free, but registration is required.
HOW TO CALIBRATE A DP TRANSMITTER
This link is to a brief, basic tutorial on calibrating DP transmitters. It includes step-by-step instructions, including diagrams and charts.
Learning Instrumentation & Control Engineering Blog
Chapter 2 of the updated version of NIST's Engineering Statistics Handbook contains a long section on calibration. The purpose of this section is to outline the procedures for calibrating artifacts and instruments while guaranteeing the "goodness" of the calibration results. It covers artifiacts, designs, artifact control, instruments, instrument control and more. The entire handbook is free and includes a printable version of the various sections.
INTRODUCTION TO CALIBRATION
This basic tutorial, "Instrument System Models and Calibration," covers basic calibration terms and techniques. By the time users have completed the free, self-directed tutorial, they should be able to explain the model of a basic instrument system; calculate the relationship between input and output for a complete system; explain and identify the main instrument system errors; explain the principles of calibration; and explain primary and secondary standards. The tutorial can either be downloaded directly or printed.
CALIBRATING VIRTUAL INSTRUMENTS
This free, downloadable PDF whitepaper, "Using Calibration to Improve Measurement Accuracy," from National Instruments addresses such questions as: How do you determine the accuracy of your virtual instrument? And, how can you maintain that accuracy? In addition, it covers other topics, such as the difference between absolute and relative accuracy; internal versus external calibration; and component versus system calibration. It also covers many options for maintaining your system's calibration.