Top 5 Insights from 2019

With a new year comes new innovation and insights. Before we jump into new topics for 2020, let’s not forget some of the hottest topics from last year. Below are the five most popular blogs from our site in 2019.

1. How to Select the Best Lighting Techniques for Your Machine Vision Application

How to select the best vision_LI.jpgThe key to deploying a robust machine vision application in a factory automation setting is ensuring that you create the necessary environment for a stable image.  The three areas you must focus on to ensure image stability are: lighting, lensing and material handling.  For this blog, I will focus on the seven main lighting techniques that are used in machine vision applications.

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2. M12 Connector Coding

blog 7.10_LI.jpgNew automation products hit the market every day and each device requires the correct cable to operate. Even in standard cables sizes, there are a variety of connector types that correspond with different applications.

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3. When to use optical filtering in a machine vision application

blog 7.3_LI.jpgIndustrial image processing is essentially a requirement in modern manufacturing. Vision solutions can deliver visual quality control, identification and positioning. While vision systems have gotten easier to install and use, there isn’t a one-size-fits-all solution. Knowing how and when you should use optical filtering in a machine vision application is a vital part of making sure your system delivers everything you need.

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4. The Difference Between Intrinsically Safe and Explosion Proof

5.14_LIThe difference between a product being ‘explosion proof’ and ‘intrinsically safe’ can be confusing but it is vital to select the proper one for your application. Both approvals are meant to prevent a potential electrical equipment malfunction from initiating an explosion or ignition through gases that may be present in the surrounding area. This is accomplished in both cases by keeping the potential energy level below what is necessary to start ignition process in an open atmosphere.

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5. Smart choices deliver leaner processes in Packaging, Food and Beverage industry

Smart choices deliver leaner processes in PFB_LI.jpgIn all industries, there is a need for more flexible and individualized production as well as increased transparency and documentable processes. Overall equipment efficiency, zero downtime and the demand for shorter production runs have created the need for smart machines and ultimately the smart factory. Now more than ever, this is important in the Packaging, Food and Beverage (PFB) industry to ensure that the products and processes are clean, safe and efficient.

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We appreciate your dedication to Automation Insights in 2019 and look forward to growth and innovation in 2020!

 

 

The Difference Between Intrinsically Safe and Explosion Proof

The difference between a product being ‘explosion proof’ and ‘intrinsically safe’ can be confusing but it is vital to select the proper one for your application.

Both approvals are meant to prevent a potential electrical equipment malfunction from initiating an explosion or ignition through gases that may be present in the surrounding area. This is accomplished in both cases by keeping the potential energy level below what is necessary to start ignition process in an open atmosphere.

What does this mean?

The term “intrinsically safe” describes a protection technique that limits the electrical and/or thermal energy of electrical equipment used in potentially explosive areas such that there is insufficient energy to ignite the hazardous gases or dust.

‘Explosion proof’ applies to an encased apparatus that is capable of withstanding a material explosion. Which means, if combustible gases entered the explosion proof housing and were ignited by the electrical energy within the housing, the resultant “explosion” would be contained inside the housing. The energy from the explosion would then be dissipated through the large surface of flanges or threads paths of the enclosure. By the time the “explosion” exits the housing, there is insufficient energy remaining to ignite the surrounding atmosphere.

How do I know which to choose?

Zone classification is one method for defining the level of risk in a hazardous area and determining which level of protection is required.

Zone 0: Area with permanent risk of explosive atmosphere of air and gas

Zone 1: Area with occasional risk of explosive atmospheres

Zone 2: Area of rare risk of explosive atmospheres of air and gas, only for short periods

Zone 20: Like Zone 0 except atmosphere of air and dust

Zone 21: Like Zone 1 except atmosphere of air and dust

Zone 22: Like Zone 2 except atmosphere of air and dust

Additional certifications and classifications used to determine both explosion proof and intrinsically safe approvals, including more in-depth divisions that explore application and environment specifics, can be found here.

Certifiably Confusing: Hazardous Area Certifications

“This is your last chance. After this, there is no turning back. You take the blue pill – the story ends, you wake up in your bed and believe whatever you want to believe. You take the red pill – you stay in Wonderland and I show you how deep the rabbit-hole goes.”

                              – “Morpheus” as played by Lawrence Fishburne in The Matrix

The first time you come into contact with the subject of hazardous area certifications, you may feel like you have chosen to take the red pill.  The topic starts off being complex, and the more you study it the more bewilderingly complex it becomes.

There are people who have devoted their entire careers to studying and learning the intricacies of hazardous area certifications and have become legitimate experts in the topic, so this short blog entry will not even attempt to offer up a comprehensive treatment.  But hopefully we can orient the newcomer to the subject with some context and provide some clues about where to start looking for more information.

Why Hazardous Area Certification?

Industrial processes must often be conducted in the presence of dangerous atmospheres or materials such as explosive gases, combustible dusts, or flammable liquids.  These substances can be ignited by sufficient energy coming from sources like electrical sparks, open flames, and hot surfaces.  Electrical equipment installed in these areas needs to be designed with some kind of methodology to prevent that equipment from becoming a source of ignition.  In most countries around the world, national and/or local governments enact electrical construction standards intended to prevent accidents and enhance the safety of people and property.  In order to ensure that installed equipment is competently designed and tested to provide the necessary level of protection, third-party agencies or “notified bodies” exist to certify that a particular piece of equipment meets the highly specialized design and performance standards for hazardous locations.

Protection Methods

Depending on the nature of the hazard and the type of electrical equipment, different protection methods – design concepts – may be deployed.  Ranked from basic to more costly, commonly these include:

  • Enhanced Safety
    • A simple level of protection intended for situations where the hazard is low and/or very rarely or intermittently present. Typically it consists of a housing with liquid-resistant sealing and gaskets that will also block the entry of gases for a limited period of time.
  • Intrinsic Safety
    • This method relies on limiting the amount of available energy in the electrical circuit to a very low threshold, such that a short or open circuit is not able to generate an electrical spark sufficiently energetic to cause ignition. It is inherently – intrinsically – safe.
  • Flameproof or Explosion Proof Housings
    • Similar approaches with different names depending on the standard being applied, the idea is to construct a robust and well-sealed enclosure around the electrical components. In the event that, for example, gases somehow get inside the enclosure and ignition occurs, the hot gases of combustion are contained inside the housing. Any gases that are vented must travel an intentionally long path that cools them to a temperature that is safe for the type of hazard present outside the enclosure.
  • Air Purge
    • Typically used for large enclosures containing power components such as circuit breakers, relays, or motor starters as well as instrumentation & control panels that contain electronic components in light-duty, unsealed housings. A positive pressure is maintained inside the large enclosure at all times to deliver fresh purge air into the enclosure and prevent the entry of hazardous gases.

Hazardous Area Classification

There are many types and categories of hazards that exist, with different levels of combustibility and different probabilities that the hazard is present.  How these areas are classified depends on the country or region where the installation will take place.  In the United States, the National Electrical Code (NEC) governs the classification of hazardous locations under two methodologies: the Class/Division system or the Zone system.  The Class/Division system is traditional in the US and the Zone system is a newer, alternative concept that is gaining wider acceptance.  Once a decision is made for a particular facility about which system will be implemented, that system is then consistently applied throughout the installation.  Canada is similar to the US but follows the Canadian Standards Association (CSA) electrical codes.  In the European Union, hazardous locations are governed by a CE (Conformité Européenne) standard called ATEX (ATmosphere EXplosive).  For the rest of the world, there may be a variety of local codes and standards, but increasingly many countries are adopting a uniform global standard called International Electrotechnical Commission Explosive or IECEx for short.  In some cases a country may accept IECEx as a basis standard and still require additional national certification for specific in-country requirements.

Selecting the Right Equipment Certification

Starting with the country where the equipment will be installed, the relevant national standards are identified.  The hazard must then be classified by an expert according to that standard.  Then the nature and type of equipment is considered and the type of protection methods that are available.  The right equipment certification is one that:

  • Is appropriate for the country where the equipment is being applied
  • Is appropriate for the classification of the hazard
  • Is appropriate for the type of equipment being installed and the relevant protection methods available

Finally, different equipment manufacturers may choose to have their products certified by different third-party agencies.  As long as the certifying body applies all of the relevant national standards and requirements, then the certifications or “approvals” provided by different agencies are essentially equivalent to one another from an electrical code / legal perspective.

Some Common Hazardous Location Symbols and Links

Factory Mutual “FM”  (US/Canada)

FactoryMutual

CSA (US/Canada)

 CSA

 Underwriters’ Laboratories “UL” (US/Canada)

UL

ATEX (European Union)

ATEX

IECEx (Worldwide)

IECEx

Navigating the Matrix

Clearly, there is a lot to know when it comes to hazardous area certifications.  As a potential buyer or specifier of equipment just trying to complete a job, it all may seem a bit overwhelming. Fortunately, you’re not stuck out there trying to go it alone. Your best bet for help in choosing the right gear is to start with the equipment manufacturer. No one is more familiar with the product and the scope of its appropriate installations, so they can offer expert knowledge and experienced guidance regarding the proper application of the equipment. And if there’s something they don’t know, they can find out for you or facilitate putting you in touch with additional resources for assistance.

Interested in valve actuator position feedback for hazardous locations?  Balluff’s TA12 linear position sensor carries world-wide certifications. To learn more visit www.balluff.us.

Intrinsically Safe Vs. Explosion Proof

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Industrial sensors are often called upon to be used in so-called “hazardous locations”.  A hazardous area is one where flammable gases and/or dusts are either present, or could potentially be present.

Typically, sensors used in such areas must be specifically approved and certified for use in these areas in order to prevent accidental ignition of any flammable gases or dusts that may be present.  The two most common protection methods are referred to as 1) explosion proof, and 2) intrinsically safe.

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