NEMA 1 are Not Just for Rating Plastic Electronics Enclosures: Mystery Debunked

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Last morning, on a 33 degree morning air I still decided to walk my dog. With this weather, I might need to wear a 2 pairs of pants, a hoodie with a long sleeve t shirt, a fleece ear warmer, and a pair of nice gloves. But I still have to consciously think about neglecting the temperature and how cold I am. I shifted my attention and I started thinking about the wide variety of topics I could blog and talk about.

While I was totally lost in my thoughts, to my surprise my puppy just started digging through my neighbor’s garbage bag and my dog found remains of their last night’s chicken dinner. So the struggle of telling my dog to drop everything has caused me trouble. I know my dog, he won’t just budge and he will not sacrifice the chicken bone he just started chewing on.

Now, with this in mind, we all know that the chicken bone is totally detrimental and dangerous for a dog. The splinters can come from the bone and it can potentially scrape my dog’s poor insides and it is no good. As a very reasonable owner of this pet, I have to give protection by restricting his access to this kind of scenarios. In just a short while, I realized that it kind of makes me a NEMA 1 protection for my dog. Except that I am not an enclosure, I am a human.

The NEMA 1 rating was defined as an electronics enclosure that is originally designed for the indoor use and it gives a degree of level of protection against the ingress of solid objects or potential contaminants (like the falling dirt.) The limited protection it provides also include the restriction of personnel for having access to harmful components.

There are different styles and some materials that are widely available for these kinds of enclosures. The metal, polycarbonate, and ABS has one thing in common: these materials can protect the electronics placed inside the enclosure from all the harm and debri. While it protects the user from the electronic.

Some companies also offers a full product line of NEMA 1 rated enclosure. As a matter of fact, the entire off-the-shelf product line can give protection to the equipment form the debris ingress and it also restricts the access of the personnel using the enclosure by giving protection to the electronics housed inside the enclosure.

Before adding vents, knockouts, and holes on the enclosure that can bring a potential effect on the rating, make sure that the applications are carefully considered when planning for the project. Once the specific rating is very important to the end use, conduct an independent testing of the final design of the product.

The Different Proposed and Accepted Revisions Concerning the Advanced Electrical Safety

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In regards to the current updates of the National Electrical Code (NEC) the 18 bodies that serves as code-making panels are making the updates in certain regulations. The National Electrical Code (NEC) was published by the the National Fire Protection Association (NFPA) together with valuable insights and inputs across different concerned and related organizations. In these organizations, NEMA was one of them. The entire body has reviewed 3,730 public inputs since January 2018. The meetings have recently resulted to 1,406 changes together with the first revisions. Some part of the initial revisions that taken place could bring a significant changes and improvements in the advancements of electrical safety concerning the build environment. With these changes in mind, it will now go through the screening of NFPA’s concerned processes. 

The Regulations and Revisions including this are: 

  • Ground Fault Protection 

The Section included in the 210.8(A) in the 2017 NEC states that it is a requirement for a ground-fault circuit interrupter (GFCI) to have a holistic protection for 15-20 amp 125V receptacles that were installed in some of the locations that are being specified in (A) (1) to (10). Some of the proposed changes in this would make GFCI protection on all 125 V through 250 V receptacles. This is because there are numerous instances and scenarios where the individuals that had electrocution while having contact or interacting with 250V receptacles across all range outlets and dryers. 

  • Surge Protection Existing in Dwelling Units 

The latest proposed requirements for all 230.67(A) equipment should be required that their surge protective devices or (SPDs) should have installation across all existing unites for dwelling service panels. This should serve as a protective barrier for the electronics and other safety device that are installed inside some of the residential structures. 

  • Disconnection for Emergencies 

The latest proposition for the 230.85 requirement would require all the existing dwelling electrical units to give provision for the emergency disconnection of installed equipment in case of emergency at a readily and easy accessible location. This proposition was given and accepted because of what was given by the first-responder organization concerned. This will eventually help in protecting the firefighters that can bring them harm because of a possible arcing event if they will choose to go back to the removal of electrical meter whilst under a possible load. 

In conclusion, these code-making panel’s main task groups discussed the 1,932 public comments that coming directly from consumers submitted because in response to the panel’s action passed last January. In overall, the meetings conducted by the code-making panels are being scheduled to take place from October 21 to November 3,2018. 

About Energy Summit that was Discussed during the Motor Summit

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If anyone would ask a child if they would allow themselves to have another scoop if their favorite ice cream flavor, they will instantly shout and yell “more please!” But even if they have shouted their hearts out, they will find out that too much ice cream can cause them stomach aches later on. This goes the same with the eve increasing energy-efficiency levels. 

Over the last 30 years of recent technology advancements, the motor industry has shown the ever increasing total efficiency of the typical 5 horse power motor from 85% wooping to total of 90%. However, the regulators in these machines together with some selected energy advocates are continuing to show or propose higher levels. There’s a requirement of certain changes concerning one area but some companies tend to forget how it should interact with the other aspect in the overall system. Because forgetting this important aspect can lead to reduced energy savings that comes with unintentional or unintended consequences. Like adding a favorite scoop of ice cream on top of the ice cream you just ate earlier, it is extremely unreasonable. To continue raising some of the efficiency levels on certain individual components does not necessarily mean that it should give greater savings on these energy products or it doesn’t mean having better products. 

While these energy motors can be manually tested and have some measurements be made, this does not mean that these tests would mean a great reduction in wasted energy. In addition and result of this observation the focus of NEMA organization has changed from doing a minimal increase in energy efficiency to focusing on a more important matter – total energy savings derived from this observation. 

The another possible conflict that may arrive at hurdling in developing an overall energy system is in terms of the possible the estimation and formulation efficiency standards to come up with the amount of energy used. This energy that is being used is intended to the usage of one certain product rather than having a single testing point for the product. In IEC 61800-9-2 Adjustable speed electrical power drive systems—Part 9-2: the Ecodesign for the energy power drive systems, power electronics and energy motor starters – the gage for the energy efficiency indicators should showcase some system drives for the several motor starters. The need for the testing of energy efficiency is shown in this regulation. Consequently, the additional steps for this is the shifting of the existing assumption and connotation that having more energy regulation is a better approach of the overall system. Compared to the idea that energy saving management achieved by having a better and more efficient management happening in the system level and increased compliance to the existing regulations, the current mantra should be shifted to this.  

In conclusion, energy companies should look at the overall savings incurred by having a more reliable system that computes the overall energy saved rather than looking at how much a device can efficiently save on energy. 

The Reliability of Having Speed Distribution and Automated Networks

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Several utilities are geared in the researching for improved and better ways for the optimization and distribution of the feeder automation through the exploration of communication services via cellular devices. 

With this in mind, the distribution feeder automation systems were able to provide as many different classifications of solutions. The main reliability improved functions that were given by the said systems explicitly includes fault locate, isolate and service restoration, and automatic transfer functionality. However, these functions can be greatly improved through the reliability of some indicators about the distribution feeders. Thus this system can be greatly centralized, decentralized, or they can have combination of both. 

The centralized systems, in its traditional way, became the primary choice of solution in the automation of the distributed feeder networks. But the said systems have the tendency to react very slowly because they have to wait for the systems that can give protection from the disconnected faults that might exist in the network. The protection is needed by the personnel before they can take action on locating the faulted feeder segment and thus lead to the reconfiguration of the feeder, and supply of alternate power in some unaffected areas. 

Some of the decentralized systems, by contrast can provide the utmost capability to have the protection and automation have synchronized functionality that exists in some of the field devices that can give faster fault isolation and system configured actions. Thus, the good combination of the decentralized distribution automation (DA) systems together with the cellular communications can provide good possibilities for the increased reliability of some distributed networks. 

In the same way, some of the low-powered unlicensed radio devices and also the recently launched direct fiber-optic cable connections became the most common methods used in data communications of some DA applications. With this in mind, the electrical utilities that uses the cellular communications is not entirely new. As the matter of fact, the usual IT service that were being used to communicated some of the field device information data back to the utility are now being used in some various systems. Such as the advanced metering infrastructure (AMI). 

The utility of the cellular communication for the transmission of data that are being used in time-critical applications such as transfer trip (DTT), fault location isolation and service restoration (FLSIR) and Automatic Transfer System (ATS) can now be used by having the reliable communication happening between linking field device controllers be secured. 

In order to make this happen, the operational technology (OT) service type to give support to the unique requirements is critically crucial. Some of the OT systems are now deterministic in nature and should be able to give the actions based on information received. Such system should require security, dependable latency, and some reliability in line with what was recently established substation protection Standards.  

The Different Advantages and Disadvantages of Auto Tuning Controls

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The three historic challenges in tuning such as: single-loop, limited success of auto-tuning, modern difficulties of model-based control – all share similar root cause. The control engineering website published a two part series on the problems of auto tuning and its nature & definitions: Part 1 in the June 2018 issue and the advantages and disadvantages of autotuning control. Part 2 in August 2018 issue. Both of these articles are very informative read and these articles can make the accurate conclusions. However they miss one of the most important main implicaitons. There is one story about auto-tuning that reveals a very valuable lesson. 

The articles somehow conclude that auto-tuning still has no panacea. Engineers rightfully suspect this. Engineers regard this as the most important problem or challenge that comes with this are the unpredictable and nonlinear process. The former is the one wherein the actual process response tends to differentiate from the pre-identified response – this is where the tuning or model I snow based. In return, it shows that this tends to be accurate for most of the processes. This is the very reason why autotuning only got limited success regardless of the number of industry attempts. In which the actual process response differentiates poses for a fundamental conundrum for tuning and modeling. 

In addition to this, it helps to understand to explain the reason why single-loop tuning and multivariable control modeling most likely to recur maintenance in practical applications. In theory, they should be one-time engineering tasks. In this case, this is the long-held reality of loop tuning and now, it has emerged as the reality of the model-based control too. 

There are two popular solutions to these problems. But these solutions do not guarantee absolute answers to these problems. One solution idea deals with average model or average tuning. Most engineers regard this as the best way to deal with this problem, however it did not solve the problem engineers have today. The second idea for solution is the autotuning or adaptive modeling. This process has a potential to bring more problematic solutions than averaging, because the basic tuning for today may not be applicable or appropriate tomorrow. 

In the vernacular sense, the process gains are subject to change. Majority – if not all – gains can be frequently or dynamically changed because of the presence of everyday disturbances in some process conditions. The returning and remodeling remain as the commonplace as they do. Adding to the limited success of autotuning, engineers testify to this. It is a common sense that people spent years doing troubleshooting process to control its performance. However, autotuning cannot solve this recurring problem. The users should take a look at the existence of the emergence of adaptive modelling, which in case attempts to do the very same thing on a larger scale – now with a critical eye.