Comcast Internet Essentials Program – A Possible Solution To Help Bridge The US Digital Divide

In collaboration with the National School Lunch Program, Comcast is attempting to facilitate understanding about the importance of the internet by offering it at a deeply discounted rate to families in low-income situations throughout the U.S, starting with Chicago. This is, simply put, a brilliant move not only to help the economically disenfranchised, but also to bolster a floundering economy that is trying to transition from an industrial marketplace to an information and service-based market place.

Called “Internet Essentials”, the program will offer Comcast’s Xfinity Economy internet service with download speeds of 1.5 Mbps for $9.95 per month and includes a promise of no price increase and fees, along with a voucher that entitles eligible families to purchase a computer for less than $150.

The Internet Essentials idea was formed after the discovery that there are 3 major barriers to widespread broadband adoption: the cost of monthly internet service, a lack of understanding about how to use the internet and the cost of a computer.

There also appears to be a perception among some that the internet is not essential to everyday life. But national research has shown that up to 3,000 new jobs can be created with just a one percent increase in the adoption of broadband internet. However, just 45% of families with annual household incomes of less than $30,000 have internet at home.

Besides the obvious advantages to these students in educational arenas now, and the national and global marketplace later, there are several reasons why widespread adoption of broadband is an important concept. For starters, there is a definite transition our society is making toward an internet-centered playing field. We communicate, socialize, gather and disseminate news, and make all kinds of decisions based upon information we exchange on the internet.

The web is becoming a strategic tool for colleges to reach out to students who otherwise wouldn’t be able to attend their school. We exchange money and goods, invest funds, and pay bills over the internet. We utilize cloud service personally and professionally to store vast amounts of data and images.

Marketing will never be the same now that the worldwide web is a major force for companies to reach out to potential customers. As mentioned previously we are transitioning from a manufacturing society to an economy that exchanges innovations, services and information. Make no mistake about it – the transition will continue as developing countries get better at filling the worldwide demand for manufactured goods, and at a much cheaper rate than the United States is able to.

In short, the internet is the greatest technological advancement of our time, and if our society is to succeed in its impending transition, we must equip all of our citizens to be able to exchange information digitally. And it begins by equipping our children to be able to navigate the internet and learn how to benefit from the vast opportunities available. This particular move made by Comcast, and surely to follow by other internet providers, is a reminder to all of us that becoming technically savvy is an important move both individually and corporately.

“Having access to high-speed Internet service allows children to do schoolwork, adults to find jobs and grow the city’s economy, and families to learn and explore together,” said Chicago Mayor Rahm Emanuel. The mayor went on to elaborate on how the Internet Essentials program is a great way for city government and the business community to provide needed solutions to the problems facing the economically disenfranchised.

In addition to discounted internet access and computer voucher, eligible families will also receive computer protection via Norton’s Security Suite and 90 minutes of digital literacy training to assist them with getting the most out of the internet for schoolwork and employment search purposes.

Families who qualify must call 1-855-8-INTERNET in order to request an application to be mailed to them. In addition to a completed application, families must also attach lunch program documents from their child’s school. They will then be notified by mail regarding their application’s status in seven to ten days.

Comcast is also putting out the call to educators, community organizations and others who want to help to bring the internet to low-income families. When these individuals complete a free registration with Comcast’s Partner Portal, they can access a free suite of tools and resources to help introduce the program to their communities.

How to Use Diamond Drilling Equipment in an Effective Way

Diamond core drilling can be an easier operation. It is possible only when you start work with equipment that is suited for that special application. Different models of such equipments are available in the market. They are easy to operate & facilitate us to complete the job easily, efficiently, quickly & perfectly. Light weight, portable diamond core drilling machines & rigs are very much suitable for drilling holes in floors, walls, ceilings & in all concrete blocks as well. Electric, Hydraulic & Pneumatic machines, rotary core & wire line are used for this purpose. Various models in electrical diamond machine are:

• Hand held electric
• Hand held electric mini
• Rig-mounted electric
• Hand held & rig-mounted electric

Han held electric mini machines are ideal for drilling holes within seconds on tiles, concrete & natural stone. Their performance is grade one when drilling is made on granite, counter tops, gravestones and also for plumbing and stonework applications. They can be used for functions like eradicating cracks & avoiding shock.

Han held electric machines are used fir to drill holes in concrete & natural stones. They are faster than rotary hammers. They are ideal for attach & installations. For drilling operation to be smooth without any shock, dust & vibrations, these equipments are employed. They function on quick change system which allows quick elimination of the center core.

Hand held & rig-mounted electric machines are highly potential & are of negligible weight. They are utilized to drill up to 5 inch holes in brick, limestone, cinder blocks & also other rough surfaces. These drilling machines are employed for the purpose of drilling very quickly. Besides, their efficiency is time-tested.

There are many types of hydraulic machines:

• Hand held hydraulic machines
• Rig-mounted hydraulic machines

These hydraulic equipments operate mechanically & they function with electronic implications. They are suitable for drilling operations. They are easy to operate & hence very much in demand for drilling functions. They bring gainful income and are durable, highly protective and very reliable.

The different types of Pneumatic machines are classified into two groups:

• Hand held pneumatic machines
• Rig-mounted pneumatic machines.
These are highly useful for drilling holes in walls, unruly bricks, ceilings, floors & all solid blocks. Diamond core drilling operations create smooth & accurate holes even through reinforced concrete, brickwork & stones. These equipments are used for different installations viz. applications for electrical systems water system, gas supply system, heating system, railway bridge construction & tunnel installation & such works.

Diamond being the hardest material can cut through all substances. Diamond wire cutting refers to the method of using wire saturated with diamond dust of varied sizes to cut through materials. This process is extensively employed as it saves time & money for a long period, saws that use wire saturated with diamond particles are used for cutting purpose. They are able to substitute other cutting tools in laboratories & factories. They are utilized for research, quality control & manufacturing.

The diamond wire technology has been instrumental in cutting nearly any material viz. single crystals, glass, silicon, metals, composites & coated or layered materials. You can expect high accuracy. Diamond does not stop with cutting/drilling/removing strong concrete metal & steel. But, it helps in installing concrete joint scale & fillers. Core drilling & wire cutting industries are developing to a great extent so much so that it goes without saying that diamond owes a lot for the success of the industry.

Internet provides you all the necessary information to locate the best core drilling & wire cutting services. There are many contractors & professionals who are endowed with skill & efficiency to complete the job in record time & well within the estimated budget.

NFPA70E, Arc Flash And Safe And Efficient Thermography Practices

What is an Arc Flash?

An arc flash is like a bolt of lightening that occurs around energized electrical equipment. It can occur spontaneously and is often triggered simply by the movement of air when an electrical enclosure is opened. The NFPA has recognized the significant hazard of arc flash and is attempting to protect workers via the latest implementation of NFPA 70E-The Standard for Employee Safety in the Workplace.

About 10-15 serious arc flash incidents occur in the US each day. Most causes of arc flash are operator induced.

Most technicians who routinely work around energized electrical equipment are familiar with arc flash-having seen it first hand. It is thought of like a major automobile accident: no one really expects it to happen to them, so people have a tendency to drive with significantly less caution than they should. So it is with arc flash, only worse. Similar to driving you can make a mistake, or you can be doing everything right when someone slams into you.

Specifically, what is an arc flash?

An arc flash is electric current flowing through an arc outside its normal path where air becomes the conductor of high thermal energy (5000ºC %2B) and generates highly-conductive plasma. An arc flash will conduct all available energy and generate an explosive volumetric increase of gases which blows electrical system doors off and potentially generates shrapnel.

What are the causes of Arc Flash?

An arc flash occurs when the gap between conductors or conductors and ground is momentarily bridged. There is always a trigger event which almost always involves human intervention. Typical causes and contributing factors include:

  • Accidental contact with energized parts
  • Inadequate short circuit ratings
  • Tracking across insulation surfaces
  • Tools dropped on energized parts
  • Wiring errors
  • Contamination, such as dust on insulating surfaces
  • Corrosion of equipment parts and contacts
  • Improper work procedures

An arc flash is electric current flowing in an arc outside its normal path where air becomes the conductor.

The vast majority of arc flash faults occur when the door is open or being opened. The National Fire Protection Agency (NFPA) is the author of NFPA 70, also known as the National Electric Code (NEC). This paper is not intended to provide a comprehensive review of the information available in the code, but merely to highlight some of the information that may be related to thermography.

NFPA 70E is the standard for safe electrical work practices.

The NEC is an electrical design, installation and inspection standard. It does not specifically address topics like electrical maintenance and safe work practices. A national consensus was needed for safety while working around live electrical equipment. NFPA 70E is the standard for safe electrical work practices. NFPA 70E addresses four specific topics: safety related work practices, safety related maintenance requirements, safety requirements for special equipment and installation safety requirements. NFPA 70 suggests that a Hazard/Risk analysis must be conducted prior to working on electrical equipment. The core of the analysis is based on shock and arc flash boundaries which must be done by a qualified electrical engineer.

Shock Hazards, Flash Hazards and Personal Protective Equipment (PPE) Selection

Prior to beginning work around live electrical components, an Energized Electrical Work Permit must be obtained and should include but not be limited to the following:

  • A description of the circuit, the equipment to be worked on and the location
  • Justification for why the work must be performed in an energized condition
  • Description of the safe work practices to be performed
  • Results of the Shock Hazard Analysis
  • Determination of the Shock Protection Boundaries
  • Results of the Flash Hazard Analysis
  • The Flash Protection Boundary
  • Identify the necessary Personal Protective Equipment (PPE) required to safely perform the assigned task
  • Means employed to restrict unqualified personnel from entering the work area
  • Evidence of completion of a job briefing
  • Energized work approval from responsible management, safety officer and owner

Prior to working with live components, the correct Personal Protective Equipment and safe working practice must be determined.

NFPA 70E allows for an exemption to the safe work permit for qualified personnel who are performing tasks such as testing, troubleshooting, voltage measuring, etc. so long as they utilize safe work practices and the proper PPE. Prior to working with live components, the correct personal protective equipment and safe working practice must be determined by carrying out a Shock Hazard and a Flash Hazard Analysis. A Shock Hazard Analysis will determine the voltage to which personnel are exposed, boundary requirements and the proper PPE necessary to minimize the possibility of shock to personnel. The shock protection boundaries are identified as limited, restricted, and prohibited for the distances associated with various voltages.

Unqualified personnel should be notified and warned of hazards by qualified personnel when working at or near the limited approach boundary. When an unqualified person must work inside the restricted boundary, it is important that they be further notified of the risks and hazards and continuously escorted by a qualified person. Under no circumstances should they be allowed inside the prohibited boundary. It is important that a Flash Hazard Analysis be conducted in order to protect personnel from being injured by an arc flash. The analysis will determine the Flash protection boundary and determine the proper PPE. In so doing, the Flash protection boundary is calculated at the distance from energized parts where a burn will be “recoverable” (2nd Degree) and “incurable” (3rd Degree). The guidelines dictate that the Flash protection boundary for systems that are 600 volts or less be 4′ for clearing times of 6 cycles (0.1 second) and available bolted fault current of 50kA or any combination not exceeding 300kA cycles. For all other clearing times and bolted fault currents, the flash protection boundary is normally determined based on the calculated incident energy of an arc fault taking into account system voltage, available current, and clearing time (where incident energy is the measure of thermal energy at a specific distance from the fault). Where it is not possible to perform these analyses (or they have not been performed), NFPA 70 provides guidelines (NFPA 70 Table 130.7-C9a) that can be used to determine the required PPE based on the task conducted. In lieu of a Flash Hazard study, selection of PPE by task is normally allowed. However, for tasks not listed in the table and for clearing times different then those listed there, a complete Flash Hazard Analysis is required. Using Flash Hazard Analysis or Task Risk Assessment, the following table can be used to identify the correct PPE:

Thermography Inspection Practices Infrared cameras have been used to identify problems in electrical systems for many years. Problems in electrical systems manifest themselves by connections and conductors becoming overheated as the result of increased resistance, the result of loose or corroded connections, or load imbalances. An infrared camera can readily identify these problems in a thermal image and is an excellent method for identifying failing or problem components prior to a failure. A failure can disable an electrical system and cause significant lost production, equipment damage and bodily injury. Insurance companies use infrared electrical inspection to help determine risk profiles and rates for industrial customers. More recently, thermographers have found that they can use IR to prevent and predict failures to help further reduce down time equipment failure and increase overall safety.

Often, during thermography inspections, panel covers are removed and subsequently replaced, a method that conflicts with the requirements of NFPA70E.

Like visible cameras, infrared cameras require a direct-line-of-site view of an object. In most cases surveys are hampered by cabinet designs that obscure the target components being inspected and thermographers are put at risk by having to open cabinets or doors in an attempt to gain access to the internal components. IR surveys of electrical systems are best conducted when the system is under heavy if not peak electrical load, which requires the thermographer to perform the inspection in and around live electrical components. Typically, electrical system covers are removed during thermography inspections and subsequently replaced. This working method conflicts with the requirements of NFPA 70E.

Recommendations of NFPA70E as they relate to Thermography Inspection

NFPA 70E recommends that only “qualified” personnel be allowed to perform work inside the flash protection boundary. Thermographers must be accompanied by “qualified” individuals if they intend to have panel covers removed. Both the thermographer and the additional person should be in full PPE. One way NFPA 70E determines Hazard and Risk and the required PPE is based on the activity that you are conducting around the equipment. Risk potentials are determined on a scale from 0-4, where 4 indicates the highest risk potential. For example, removal of a bolted cover on 600V equipment carries a hazard/risk classification of 3 and that goes up to a rating of 4 on voltages greater than 600V. As this work occurs within the Flash Protection boundary, the appropriate PPE must be worn. The required minimum PPE for Hazard/Risk Classification 3 work is to withstand 104.6 J/cm², and the required minimum PPE for Hazard/Risk Classification 4 work is to withstand 167.36 J/cm². As much of the work performed for an IR inspection requires removal of bolted covers, this would be the PPE that is required.

Infrared Windows: Eliminate the Controllable Risk

The first rule in any risk assessment is to eliminate the risk if possible. Infrared Windows eliminate many of the risks associated with live inspections since they enable an infrared camera direct view of live electrical components without the need to open electrical enclosures. They provide an excellent means of accessing electrical equipment efficiently and safely. In addition, a second qualified technician is not required to open and unbolt enclosures. An IR viewing window is basically an infrared transparent material with a holder/mounting body. Thermographers may even decide to not use a window when inspecting energized components at some distance from the cover and use a protective grill in place of a window. The grill must be IP2X certified (the grill size must offer protection against foreign objects with diameters larger than 12mm). This method can significantly reduce the window cost and also has the additional benefit of allowing ultra sound inspections of the electrical switchgear. However when using grills, operators will be exposed to live electrical components and they must wear the appropriate level of PPE identified from the Arc Flash Hazard Analysis of the switchgear. Infrared Windows eliminate many of the risks associated with live infrared inspections since they enable an infrared camera direct view of live electrical components without the need to open electrical enclosures. The optics holder design depends upon a number of parameters: the field of view, equipment lens and window size are all functions of the design and must meet all the parameters that the thermographer requires before a holder is manufactured. Also, a protective cover should be included in the design as crystals are very expensive and in some cases, extremely fragile. Infrared Windows are available in multiple sizes and can be custom made to retrofit dead fronts on distribution and isolator boards. The larger the size of the window, the greater the field of view one can see with their IR camera.

Considerations in Installing Infrared Windows

To correctly install infrared windows, the targets that require inspection must be identified. Typically, traditional surveys only look at the bolted connections within the switchgear. These are generally considered to be the “weakest points” or “points most likely to fail.” These may include:

  • Cable connections
  • Bus Bar Connections
  • Isolator or Circuit breaker connections

The formula for calculating the field visible through an Infrared Window is: FoV = 2 x tan (angle/2) x D, where FoV is the width of the object area that will be viewed, the “angle” is the angular field-of-view of the camera, and “D” is the distance from the camera (ostensibly the window) to the objects being viewed. Once a decision has been made about what objects are to be inspected through the infrared window, the number of windows and appropriate size must be determined as well as where they need to be installed to ensure best coverage (and therefore maximum efficiency). The size of the infrared window will depend on several factors, including the infrared camera’s clear aperture, its ability to focus on close objects, its ability to be placed as close as possible to the window, the camera’s angular field-of-view and the amount of manipulation is possible with the camera when viewing through the window. An important consideration is how the infrared camera can be manipulated when looking through an infrared window. A high degree of manipulation can have the effect of increasing the size of the inspection area by up to a factor of 3. This means that if the object under observation is 12 inches across, depending on several factors, it is possible that a window diameter of 4 inches (for IR window size calculation purposes) can still be used if the operator manipulates the camera from left to right or up and down.

The required size of the window will depend on the following:

  • the size of the objects to be viewed and their distance from the panel cover;
  • the infrared camera’s angular field-of-view and clear aperture;
  • the camera’s ability to focus on close objects and to be placed close to the window.

Typically, infrared cameras have a horizontal field of view of 25°. Those infrared cameras that offer a wide-angle lens option (for example 50°) permit the user to have a substantially wider field of view, resulting in an increase in viewing area through the same infrared window size. This can be a great advantage in certain situations, reducing the size and possibly the number of windows. Other useful infrared camera features are close focus capability, small lens diameter resulting in a small clear aperture, motorized focus (eliminating the need to get fingers on the lens focus ring and moving the camera away from the window) and a chassis design that facilitates movement at the window such as an articulating camera head that allows the user to look into windows above eye level or at near floor level.

The View through an Infrared Window

An infrared window allows a camera operator to inspect the inside of an electrical cabinet to check the physical condition of the components that you have chosen to inspect. As with traditional thermographic inspections we can see temperature differences very clearly. You need to have the confidence in the infrared windows that you are using. They are designed to allow infrared energy to transmit through them at a known transmission rate; therefore, if there is even a slight temperature difference you will be able to see that with your IR camera, and be able to record images for the IR inspection program.

Considerations for Installing Infrared Windows

Installing an infrared window requires cutting holes into very expensive switchgear. Therefore, it is very important to be very sure that they are installed in the correct location and that the switchgear ratings are not degraded in any way. Before installation, the following factors need to be considered:

  • NEMA or IP rating of the switchgear and IR windows: Remember to never install an IR window of a lower rating than the rating of the switchgear.
  • Test Certifications: Ensure that the IR windows have been tested and approved by the certification bodies as the switchgear for which they are intended (i.e. UL, IEEE. Lloyds).
  • Internal obstacles: Before removing internal Perspex/Plexiglas covers or cables, ensure that the local safety manager’s approval is sought first. In some cases you may not be able to totally remove the covers and may only be able to modify them by drilling or punching holes to retain the IP2X requirement for some switchgear.
  • Explosion Ratings (if applicable): Some panels are positioned in intrinsically safe areas and as such can never be modified in the field.
  • Dielectric Clearances: Where IR windows use grills or inspection orifices, they must comply with IP2X (13mm 0.5″), and clients must be made aware of the safe dielectric clearances for the type of switchgear that they intend to install the window into. The table shown at the left (from IEEE C37.20.2 table A.3) specifies minimum distances from live components, and it is recommended that these be considered as a standard for grills/inspection orifices.

When using Infrared Windows, it is important to correct for the transmission specification of the window and the emissivity of the component that is to be inspected through the IR window. One way of correcting for the effects of the window is by adjusting the camera’s emissivity value for an object of known temperature until the camera’s reading is correct. For objects at the same ambient temperature and emissivity, the new emissivity value can be used.

When using Infrared Windows, it is important to correct for the transmission loss of the window and the emissivity of the component that is to be inspected through the IR window.

Another way of using IR windows is to prepare all components that are to be inspected so that they have the same emissivity (for example, with electrical tape, emissivity paint, IR-ID Labels). In this case, all components being inspected will have the same transmission rate and emissivity readings; consequently, the results gathered will be far easier to compare.

Can IR Windows Carry a Generic Arc Rating?

Electrical switchgear takes on many different shapes and sizes. The surface areas and volumetric elements of the cabinets are different with each model, type and rating. Each cabinet is subjected to the testing that is laid down by the certification bodies such as UL, IEEE, etc. This test is completed on the cabinet assemblies and not the components that make up the assembly. Electrical cabinet designs and dimensions are infinite, and we therefore CANNOT or MUST NOT use the data from one cabinet design for another design unless they are identical in every way. This is why components never carry a generic arc rating and must be subjected to industry standard tests to confirm that they conform to the minimum required level of mechanical strength and environmental properties for the electrical cabinets and assemblies which they are going to be fitted into.

Conclusion

Because of the frequent occurrence of arc flash in industry, it is extremely important to be aware of the risks associated with inspection of high voltage switchgear and related items. Concerns about operator safety due to an arc-flash event are causing inspectors to adopt new practices in accordance with NFPA 70E, the standard for safe electrical work practices. Shock and Flash Hazard analyses are required in many situations. Personal Protective Equipment recommendations are also available. One new common safety practice involves the use of infrared transparent windows which eliminate many of the risks associated with live infrared inspections since they enable an infrared camera to have a direct view of live electrical components without the need to open electrical enclosures.