Voices: Feedback

Reader Feedback: When Should You Calibrate Your Industrial Devices?

A Reader Says "You Should Calibrate Your Instruments With the Frequency You Established in [Your] Plan, and Never Go Longer Than a Year"

By Armando Farfán

[This comment appeared on the ControlGlobal LinkedIn page referencing senior technical editor Dan Hebert's column, "Calibration Can Be Conditioned-Based."]

If your process is involved in quality standards, such as BRC, HCCP, etc., then you should calibrate your instruments with the frequency you established in [your] plan, and never go longer than a year. Just try to minimize your critical control points, be smart, work hard, and you will find a thin and adequate list.
If you're not suffocated by quality, first of all you should have this basic element: a list of plant instruments with their criticality (high, medium, low). Such criticality must be clearly established in your main maintenance manual [in terms of] impact on production, impact on environment, level of safety and health risks, etc.

Once you reduce your entire list to a handful, its time to evaluate the inspection period for such instruments.

Remember the "bathtub" figure "percent fails against time" for electronics equipment: high percentage in the first hours of life, steady figure during the working life, and high percentage in the final stage of its life.

This figure tells you, "Take your hands out of the instruments unless they show signs of malfunction." In other words, if it works, don´t mess with it. The signs of malfunction could be established from a condition-based monitoring routine inspection period. At the end, I agree with controlglobal.com.

Armando Farfán
PLC Network plant in Tucumán

More from this voice

Title

Reader Feedback: Old Dogs Learning New Tricks

Why Are We Still Using the Same Sample Preparation Techniques That We Used 40 Years Ago?

01/14/2014

Reader Feedback: Why Is Alarm Management Such a Problem?

What's the Cost of Best Practice Alarm Management?

01/14/2014

An Alarming Disconnect?

The Values of Alarm Limits Are the Biggest Single Factor Governing Alarm Performance

02/14/2014

Cyber Vulnerabilities

Defending Targeted Attacks Is a Higher Bar. Focus on Prevention Alone Is Probably a Mistake

02/14/2014

Boiler Tuning Question

What Is the Best Method to Tune PID Values for Three-Element Drum Level Control in the Boiler?

02/14/2014

Reader Feedback: Replacing a Field Device

Is the 3 a.m., Sunday Morning Replacement the Killer App?

03/05/2014

Reader Feedback: Pervasive Sensing

Our Vision of Pervasive Sensors Encouraged Us to Find Innovative Ways to Not Just Power Sensors

03/05/2014

Reader Feedback: No Complete Disconnect for Nuclear Plants?

You Can't Isolate a Nuclear Power Plant from Any External Data Communications

04/07/2014

Reader Feedback: When Should You Calibrate Your Industrial Devices?

A Reader Says "You Should Calibrate Your Instruments With the Frequency You Established in [Your] Plan, and Never Go Longer Than a Year"

04/07/2014