Safety Standards Must Be Made Simpler

Who Should Have the "Last Word" on Safety, the Machine or the Operator?

Bela Liptak
CG1501 LL

I was in a joking mood when in my November column on SIS, I referred to the camel being a horse designed by committe. I apologize for that, I did not intend to offend the committe. I know that the members of the IEC61508 and other committes (for decades, since 1998) worked very hard and deserve our thanks. My goal with the November coulumn was to move our safety standards away from equations filled with acronyms and towards quantifiable and practical improvements, and not be turned off by anything or anybody. Let me start this second column on safety standards by restating that they must become made simpler, more practical, more quantifiable and focused on the whole…

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Timeless Resources

Beginner's Guide to Differential Pressure Level Transmitters

By David W. Spitzer

The importance of level measurement cannot be overstated. Incorrect or inappropriate measurements can cause  levels in vessels to be excessively higher or lower than their measured values. Low levels can cause pumping problems and damage the pump, while high levels can cause vessels to overflow and potentially create safety and environmental problems. Vessels operating at incorrect intermediate levels can result in poor operating conditions and affect the accounting of material. Learn more.

Controllers: Direct vs. Reverse-Acting Control

By Bela Liptak

Valve failure position is determined by safety considerations. If, in case of failure, you want your column to go on full reflux, your selection where the reflux control valve is fail-open, and net overhead control valve is fail-close, is right. Assuming that the valve actuators are spring-operated pneumatic ones, and assuming that you define "failure" as the loss of air supply, the spring will act to open a fail-open (FO) valve and to close a fail-closed (FC) valve, regardless what the controller actions are. Read more.

Voices: Ask The Experts

Modeling the Weather, Measuring Bulk Solids with Radar and Benchmarks for Loop Checking Productivity

Our Experts Tackle Three Difficult Questions

By Béla Lipták

Q: Modeling the Changing Weather A couple of years ago I asked you if the knowledge gained in controlling industrial processes would also be useful in modeling global ones, and you showed why it would. Now I would like to ask a more specific question. How would you go about modeling the…

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Control Talk Blog

Why Tuning Tests are Not Repeatable Tips

Each process test will typically give a different result in the process dynamics identified and consequential tuning settings calculated. Here we look at the sources of this lack of repeatability, the implications, and what can be done to improve tuning tests.

Control Talk Blog

Most Recent

  • Safety Standards Must Be Made Simpler

    By Bela Liptak

    I was in a joking mood when in my November column on SIS, I referred to the camel being a horse designed by committe. I apologize for that, I did not intend to offend the committe. I know that the members of the IEC61508 and other committes (for decades, since 1998) worked very hard and deserve our…

    Full Story
  • Motors and Drives: Process Automation Driving Forces

    MEDIUM-VOLTAGE AC DRIVE MV1000 medium-voltage ac drives combine compact modular design, high efficiency and a good MTBF rate. Smart Harmonics technology reduces input total harmonic distortion to less than 2.5% without filters, which exceeds the requirements of IEEE519-1992. It also provides…

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  • Online Resources: A Splash of Flow Instruments

    FLOWMETERING IN FIVE PARTSThis five-part tutorial covers the basics of flowmeter technology in five parts. Part 1 introduces the basics; Part 2 deals with pulse-based counter in flowmeters; Part 3 discusses pulse samplings and counting; Part 4 introduces ultrasonic flowmeters; and Part 5 outlines a…

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  • Control Readers Name the Best Process Automation Suppliers of 2015

    By Control Staff

    The readers of Control have selected the best process automation products and suppliers in the 2015 Control Readers' Choice Awards. As in past years, the class of 2015 is marked by consistent quality, innovation and the hard-won trust of their customers. And while the consistency of years past is…

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  • Here's How Control Automation Could Have Prevented Past Accidents

    By Katherine Bonfante

    Process control authority and Control Columnist Béla Lipták says proper control automation could have prevented many accidents that occurred in the past. In fact, Lipták's Ask the Experts columns touch on this very same subject. "Half of our industrial accidents are caused by human error," says…

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