Author: admin (page 1 of 14)

How Will We Know if We Should Replace or Recondition Large Scaled Electrical Equipment?


Transformers are used in industrial and manufacturing settings as a way to control the electricity infrastructure within a facility.  They are used to step up and power down different voltages of electricity to equipment throughout.  The longevity of transformers comes down the environment in which they are ran and the amount of usage received.  A typical end of life period for transformers under average usage is somewhere between twenty to forty years.  Factors other than age are often used to consider if a transformer should be replaced.  With this in mind, many facilities are considering refurbishing older transformers that are still showing signs of good health instead of replacement. 

In the following installment we will look at the many reasons that refurbishment of transformers is becoming popular verse replacement.  We will also look at why some transformers can be refurbished and why others shouldn’t be.  There are limitations to refurbishing transformers that we will look into as well. 

Why Choose to Refurbish Verse Replace?

Refurbishing Transformers Saves Money and Time

The cost to refurbish a transformer is substantially less than purchasing a brand new one.  Cost is definitely a factor in refurbishing, but it is also important to recognize the time saving.  The time to refurbish a transformer is substantially less than the time it takes to procure a new piece of electrical equipment for your facility, such as a transformer.

Buying new equipment often comes about through a lengthy process that requires approval from a number of sources before it can be completed.  It is also considered a capital expense which many facilities try to budget ahead for.  Refurbishment is often classified as a revenue expense which doesn’t often require approval.  Extending the life of quality assets is good for business and refurbishing can achieve this without risk. 

Extended Transformer Life

We are all responsible for doing our part in creating a sustainable environment to leave to generations to come.  The environmental impact of manufacturing and equipment disposal is not something that is taken lightly.  Reconditioning transformers and other large scaled equipment helps to demonstrate environmental sustainability which is not only showing corporate responsibility but also regulatory consciousness.  Prolonging the life of large scaled equipment through reconditioning is just one way to exhibit your company’s commitment to environmental impact as well as to the confidence that the plant will continue to operate efficiently without risk of unexpected failure.

If you do find that you have had to replace a transformer for a reason other than failure, the older transformer can be refurbished and kept as a spare.  In order to determine if a transformer can be refurbished it is necessary to assess the transformer.  The extent of reconditioning needed to make it like new again may be deemed too much.  However, when refurbishment is deemed appropriate, the transformer is brought to a dedicated facility where reconditioning can be performed. 

J & P Electrical Company is a full-service electrical company that supplies contractors, end users, and supply houses with new surplus, quality reconditioned, and obsolete electrical equipment. We purchase a wide range of electrical equipment such as bus plugs, bud ducts, panel switches, substations, and transformers.  More information can be found at https://www.jpelectricalcompany.com



Seasonal power demands overload circuits

(Norma Vally) Seasonal demands on power, such as the addition of space heaters, can overload electrical circuits.

(Norma Vally) Seasonal demands on power, such as the addition of space heaters, can overload electrical circuits. By Norma Vally Home Matters January 30, 2019 – 4:09 pm  

Lower temperatures this time of year have increased people’s use of space heaters. These units, while small in size, pull more energy than expected, especially in older homes. Without an upgraded electric service, circuits overload and breakers trip when this type of appliance is added to a line while other devices are in use.

Overloading a circuit comes with risks. According to the National Ag Safety Database: “Overloaded outlets and circuits carry too much electricity, which generates heat in undetectable amounts. The heat causes wear on the internal wiring system and can ignite a fire.”

To be clear, when I say “overload” I mean a response to a circuit when many things are plugged in and running at the same time. A response can range from dimming lights to actually tripping the breaker. A breaker is designed to trip “off” when the power load (measured in watts) exceeds the amount of amps a single circuit breaker can handle.

Most circuit breakers in your service are 15 amp. Conservatively, on a 15 amp breaker you can use 80 percent of its amperage all at once, which is 12 amps. This means no matter which outlet you’re using on a particular circuit, or how many things you have plugged into it, the total load should not exceed 12 amps or you risk tripping the breaker.

The question becomes, how is someone supposed to know how many amps are being pulled based on watt usage? There’s a formula — watts/volts=amps — and once you know what numbers to plug in (pun intended), it’s easy to calculate.

Becoming acquainted with basic electric lingo will be helpful as well. Know that watts is a unit to measure “power.” Volts is the pressure by which electrons are being “pushed.” Amps is a base unit of electrical “current.”

FYI, in the U.S. our lines are 120 volt, unless doubled for larger appliances, becoming 240-volt circuits.

You should also know what switches and receptacles are on what breakers. Breaker box mapping can be disheartening in older homes where you’ll discover several rooms, including a bathroom, are all on one 15-amp breaker — hence the bedroom lights dimming when someone uses a hair dryer in the bathroom.

Here’s a practical example: If you’re using a 1200-watt microwave on a 120-volt line, it will pull 10 amps (1200w/120v=10amps), leaving you with only 2 amps on that circuit (remember, max usage on a 15-amp breaker is 12 amps). So let’s say while you’re heating up a plate of leftovers, on the same circuit, someone starts up a 1500-watt space heater … pop, that breaker will trip (1500w/120v=12.5amp, plus the 10 amps from the microwave, a total of 22.5 amps) well exceeding the 15-amp breaker.

Receptacles that serviced homes built several decades ago fall short given today’s demands from electronics, appliances, etc. One outlet in a medium-sized room sufficed back in the ’30s and ’40s. Today, the standard electrical code is one receptacle every 6 feet. While an older home may only have a 100-amp service, today the same size home will have 200-amp service or more.

The truth is it doesn’t matter if you have two or 200 outlets on one circuit (to exaggerate a point); it will only overload if you’re using more amps than what that particular circuit breaker is designed to handle. When we add a space heater or any device that pulls hundreds of watts at once, we should always assess what other devices are on the same circuit that may run simultaneously.

Splitting up the number of outlets being used to multiple breakers will solve an overloading problem. I make this statement provided there are no age-related issues in your wiring, such as worn-out insulation. At any rate, adding breakers to your service is definitely a job for a licensed electrician.

A good electrician will first determine the condition of your wiring, if you can add breakers to your existing service and if your service panel needs upgrading (and what permits may be required), and give you an estimate of how much the project will cost.

Original Source: https://bouldercityreview.com/community/seasonal-power-demands-overload-circuits-50475/

Written By: Norma Vally Home Matters

Published Date: Jan 30 2019


What Is an Air Breaker and How Do They Work?


Just as molded case circuit breakers, MCCB, air circuit breakers, ACB, is device that is in place to provide protection from an electrical surge or short-circuit.  The main difference is the amps they protect; ACB can withstand higher short circuit currents and mechanical stress because of the arc extinguisher element then MCCB can.  There are a variety of air circuit breakers and switching gears available to purchase.  Air circuit breakers have replaced oil circuit breakers because of their resiliency, performance, ease of installation, and low maintenance level. 

Three Types of Air Break Circuit Breaker

The three main types of air break circuit breakers include: plain break, magnetic blowout, and air chute.  Their main application is for use in maintaining indoor voltage and switch gears.

Plain Break

The simplest of all air circuit breakers is the plain brake.  Two horns shape the main point of contact.  This creates an arc that extends from the tip of one to the other. 

Magnetic Blowout

In higher voltage capacity’s, up to 11KV, magnetic blowout air circuit breakers are used.  The arc extension gets by the magnetic field that is made from the current in blowout coils.

Air Chute

Air chute air break circuit breakers have main contacts of copper and conduit which are in the closed position.  They are most often silver plated and have a low contact resistance.  The arching contacts are created from copper alloy and are resistant to heat and are solid. 

Air circuit breakers are most often used for controlling the power station auxiliaries and industrial plants.  They provide protection to electrical machinery such as transformers, capacitors, and generators.  Where ever there is a possibility of fire or explosion, air circuit breakers are most often installed.   They offer a higher resistance to power that allows an increase in the resistance of the arc by splitting, cooling, and lengthening.  The main drawback in air circuit breakers is that the arc chute principle is less efficient under low currents where electromagnetic fields are weak. 

J & P Electrical Company is a full-service electrical company that supplies contractors, end users, and supply houses with new surplus, quality reconditioned, and obsolete electrical equipment. We purchase a wide range of electrical equipment such as bus plugs, bud ducts, panel switches, substations, and transformers.  More information can be found at https://www.jpelectricalcompany.com



CES 2019: Currant Introduces First AI-Powered Smart Wall Outlets

CES 2019: Currant Introduces First AI-Powered Smart Wall Outlets

AI moves into your wall power outlet.

Currant the Currant Smart Wall Outlet ahead of CES 2019. It will be the first AI-powered in-wall smart outlet that analyzes power usage and creates personalized, easy-to-implement suggestions for consumers, contractors, business owners, and real estate managers to automatically power off devices and appliances, cutting excess electricity usage and helping to save money on electric bills. Currant’s Smart Wall Outlet will be available in a 15 amp version for homes and a 20 amp outlet designed for the commercial market. Both the home and commercial models can be controlled by the Currant App, Amazon Alexa, or Google Home.

The new Smart Wall Outlet is designed to replace traditional outlets with duplex tamper-resistant receptacles that can be easily installed in commercial businesses and new construction as well as consumers’ existing homes. Each in-wall unit analyzes real-time electricity usage, displaying it in intuitive graphs that break down energy consumption and cost by hour, day, month, or year. Customers can use the Currant App to monitor anything plugged into the outlet, effectively controlling power running through the outlet to ensure that they’re fully in control of all their devices and appliances, whether they’re down the street or across the country. And, like all Currant outlets, Smart Wall Outlet models are calibrated using high-precision test equipment.

In addition to Smart Wall Outlets, Currant also announced that it has added a number of new features to its WiFi Smart Outlets. Available January 8, these features include the ability to lock the outlet so it cannot be turned on or off except through the app, which is particularly useful for parents looking to prevent kids from using certain appliances for safety reasons, such as an iron, or who want to set limits on gaming consoles.

Outlet locking is also valued by people who want to prevent things like a WiFi network from cutting out in the event someone accidentally turns it off, or business owners who want to shut off power to specific outlets or devices and not enable them to be turned back on from the outlet itself. In addition to the ability to lock the outlets, Currant will offer customized alerts that notify people when their rules take effect and when devices are using certain levels of power.

“We are on a mission to help reduce the insanely high levels of energy consumption in the United States,” said Hasty Granbery, founder and CEO of Currant. “To that end, we are thrilled to announce our newest offering in what will be a long line of energy-saving smart home and commercial products. Currant Smart Outlets will work in essentially every environment — home or commercial space. We can help anyone cut energy consumption, save money, and make a positive impact on our world without any inconvenience to their day-to-day lives or activities.”

Currant Outlets run on both WiFi and Bluetooth, assisting with ease of setup and control. The Currant Smart Wall Outlets will work seamlessly with existing Currant Smart Outlets, creating a Bluetooth Mesh Network throughout the building that can be used to control any outlet within range, enabling control in areas where a WiFi network is weak or unavailable. In addition, when several Currant Outlets are used together, the outlets can prioritize which communication protocol to use so only a subset of outlets are using WiFi.

Customers can get started with an in-wall outlet within minutes and easily connect to the Currant App, which is available for iPhone and Android. The app automatically detects the outlet and displays real-time information on energy usage. Customers can opt to set outlet-specific rules right away in order to turn the power on and off according to their preferences and schedules or they can use it as a normal outlet before receiving tailored suggestions for usage based on what is plugged into the outlet, the amount of energy consumed, and any unique usage patterns for the space.

Original Source: https://www.i4u.com/2019/01/130610/ces-2019-currant-introduces-first-ai-powered-smart-wall-outlets

Original Date: Jan 3 2019

Written By: Luigi Lugmayr

Preventing electric fires during the holidays

Posted By: Trent Bailey December 12, 2018

HOUGHTON — During the winter months, fire departments see an increase of house fires often times causing serious injury or worse. That’s generally attributed to residents trying to battle the cold temperatures with additional heating sources. ABC 10’s Keweenaw Bureau Reporter Lee Snitz has some tips on staying safe this winter.

The Christmas tree is found in most American homes this time of year with twinkling lights, sometimes candy canes, and an assortment of ornaments, but it has also been known to devastate a family’s holiday season in some cases.

“Too many lights on one circuit creates a problem with the circuit itself and then you have the house fire,” said Bill Sheetz, an electrician with WLS Electric. “The breaker systems on the electrical services are getting much better at stopping overloads.”

Energy efficient LED lights and other advancements in technology may be showing a decline in tree related house fires, but residents should be aware that there are plenty of other hazards in their home.

“Electric space heaters are temporary supplementary heat which is not permanent and most people use it as a permanent source of heat and they also overload the circuits and typically cause a lot of house fires.”

Space heaters are not necessarily a hazard themselves, but they do use a lot of electricity, and if they’re running for a extended period of time- they can create heat in the wiring of a home and that can cause an electrical fire if the wiring is outdated or inadequate. If your running a space heater in your home or business its a good idea to unplug everything else that is using that circuit. This will help to prevent an overload. And a big No No is replacing blown fuses or circuit breakers with one that is larger than specified.

“Typically when were talking about fuses, were talking about services that are over 40 or 50 years old,” said Sheetz. “They have a twist in fuse and a lot of people blow the fuse so they go to the local hardware store and the guy gives you a 30 amp fuse where you should have a 15 amp fuse. The reason behind the 15 amp fuse is to protect the wire behind the wall. So when you put the larger fuse in you create a lot of heat on the wire behind the wall that you don’t see until the fire department shows up at your house.”

Another precaution that is essential is checking the alert systems in your home.

“Most people if they have older homes, they have battery smoke detectors which are fine as long as you check them regularly. We go into homes all the time and they’re just not working. And the reason they’re not working is because the battery is dead. It looks good on the wall ceiling but it doesn’t work if the battery isn’t working for you.”

When buying batteries for those gifts that are labeled with the all too familiar phrase “Batteries Not Included”,  it’s a good idea to pick up a couple of extra 9 volts and replace what’s currently in your smoke detector. It could save lives if the unthinkable were to occur.

“The main thing is if your breaker or your circuit, anything pops in your home, trips or stops working. Don’t go to your local hardware store and ask for help. Please call a qualified electrician because that’s where we have a lot of problems. People will introduce things that may work, but aren’t correct.”

Original Source: https://abc10up.com/2018/12/12/preventing-electric-fires-during-the-holidays/

Original Date: Dec 12 2018

Original Author: Trent Bailey

Generator Tap Boxes: Instant Power During Power Outages


No matter what business you are in, be it manufacturing, banking, health care, or education a sudden change in the power situation can be a debacle.  A loss of power means a loss of time, resources, and more so it is imperative to prepare for just such an occasion. 

 To plan ahead to avoid an electrical interruption companies could choose to install a permanent generator. An installed permanent generator can be a large maintenance expense.  To avoid this extra expense the installation of a tap generator is a viable, cost effective option.  When a natural disaster like storms,blackout, and what not a tap generator allows businesses to get your electricity back up and running quickly. 

A tap box is a simplistic generator that is installed outside of the business.  It plays the role of connecting the business’s portable generator to the electrical system.  This allows you to get a temporary supply of electricity running to avoid downtime.  This connection can be made either manually or using an automatic transfer switch.  The power is generated so efficiently that it can be up and running without any delay using programable logic circuits and auto start generators.  Your power system will be emergency ready and the cost savings of no down time and not having to hire a professional electrical contractor to temporarily connect power will be pay off the first time the power goes out.  Being prepared ahead of time pays off.

When having a generator tap box installed you will want to assess your electrical needs.  The needs and requirements that your specific business have will vary from even your competition.  Here are some things to consider when choosing a generator tab box

  • How often do you lose power?
  • What are your electrical needs?
  • What systems are crucial to keep running?
  • What is your budget?

No matter what the answers are to these questions, J & P Electrical will have a solution that fits your exact needs. 

J & P Electrical Company is a full-service electrical company that supplies contractors, end users, and supply houses with new surplus, quality reconditioned, and obsolete electrical equipment. We purchase a wide range of electrical equipment such as bus plugs, bud ducts, panel switches, substations, and transformers. More information can be found at https://www.jpelectricalcompany.com



New Circuit Breaker from Schneider Electric Features Increased Safety Requirements

Schneider Electric’s new low voltage power circuit breaker takes is top in power system uptime and energy efficiency due to its onboard Ethernet communications and Class 1 (≤1% error) active power metering accuracy built into every circuit breaker. It has a wireless remote control of the circuit breaker through Bluetooth to keep maintenance staff outside of the arc flash zone during operation. The new circuit breaker features new IoT enhanced digital capabilities such as wireless communication, customizable and downloadable applications, integrated analytics, and advanced metering and sensing technologies that work with evolving industry challenges. It is tailor made for the application and modified at any time in the future without de-energizing with its digital modules. The device is built with the new Micrologic X control unit. The breaker can be upgraded by service and maintenance personnel or facility staff as new code requirements and regulations are implemented along with evolving customer needs. These upgrades can be implemented by simply downloading a Digital Module from Schneider Electric’s secure GoDigital online marketplace and installing it into the control units using the complimentary Ecoreach configuration software, adding new functionality within minutes.


Original Press Release:

Schneider Electric Introduces its Square D Brand Masterpact MTZ Future Ready Low Voltage Power Circuit Breaker

– Revolutionize power distribution through digital customization optimizing the EcoStruxure Power Platform Industry-first Bluetooth and NFC capabilities with companion smart phone app allows operation by maintenance staff outside of the arc flash zone

– Best-in-class in system Uptime and efficiency

BOSTON, Nov. 14, 2018 /PRNewswire/ — The world is facing critical change. As a result, the electrical industry is meeting challenges of more stringent regulations, tighter sustainability goals, increased safety requirements, and the need for more reliability and flexibility. Schneider Electric is leading this evolution with the launch today of its next generation Square D brand Masterpact™ MTZ low voltage power circuit breaker.

The Masterpact MTZ circuit breaker takes the lead in power system uptime and energy efficiency with its onboard Ethernet communications and Class 1 (≤1% error) active power metering accuracy built into every circuit breaker. It also allows wireless remote control of the circuit breaker via Bluetooth LE keeping maintenance staff outside of the arc flash zone during operation. These innovative advancements in technology are an industry first.

As part of Schneider Electric’s comprehensive EcoStruxure™ Power Platform, the Masterpact MTZ is an industry leading, world class circuit breaker with all new IoT enhanced digital capabilities. It includes wireless communication, customizable/downloadable applications, integrated analytics, and advanced metering and sensing technologies that address evolving industry challenges. With the introduction of digital modules, the breaker is tailor made for the application and modified at any time in the future without de-energizing.

From installation, operation, maintenance, and digital upgrades, Masterpact MTZ brings a whole new level of power circuit protection and control to large and critical power distribution applications. Masterpact MTZ circuit breakers will transform how facility and building operations managers achieve efficiency, safety, reliability, and equipment protection goals. Masterpact MTZ is available for new installations and can be retrofit into the space of an existing power circuit breaker.

The Masterpact family of low voltage power circuit breakers have been the industry benchmark in electrical distribution for three decades – first with the Masterpact M, followed by the Masterpact NT/NW, each known globally for legendary performance and reliability.

“The new Masterpact MTZ is a game changer,” says Duke Dunsford, USA Marketing Launch Manager for Masterpact MTZ. “The Masterpact MTZ connectivity and digital capabilities seamlessly integrate into our EcoStruxure Power architecture, delivering significant benefits for end users, specifiers, panel builders and contractors who can better serve their customers’ needs with this new capability.” He continued, “With the standard Bluetooth wireless capability on every breaker, the phone in your pocket now becomes a powerful tool in the operation of this new platform.”

The new generation Masterpact MTZ is built with the new Micrologic X control unit that puts it ahead of its class. One of the advancements in the Masterpact MTZ line is its future driven upgrade capabilities. As new code requirements and regulations are implemented along with evolving customer needs, the breaker can be upgraded by service and maintenance personnel or facility staff. Upgrades can be implemented by simply downloading a Digital Module from Schneider Electric’s secure GoDigital online marketplace and installing it into the control units using the complimentary Ecoreach configuration software, adding new functionality within minutes.

“Masterpact MTZ is loaded with practical, usable features that take low voltage power circuit protection and control to a new level,” says Mr. Dunsford. “In case of a power outage, users can simply utilize their smartphone’s wireless connection to diagnose the issue and minimize downtime. Another unique feature includes capturing waveform data during tripping events and can be accessed even without power. The smartphone app also can provide a root cause explanation and step-by-step breaker reclosing instructions to re-energize your system. This can save critical time for customers looking for details during an outage.”

Additional benefits of the Masterpact MTZ circuit breaker include:

  • Downloadable digital modules can be installed without downtime for maximized flexibility and operational efficiency
  • Along with Bluetooth, Near Field Communication (NFC) is included allowing your smart phone to monitor the circuit breaker’s condition even in a power outage
  • Event notifications and overload prevention are optimized with real-time monitoring and alarm capabilities both for Ethernet monitored systems and on mobile devices
  • Seamless integration of Masterpact MTZ into Square D branded power equipment such as switchgear, switchboards, and motor control centers using the newly designed embedded Ethernet connection

For more information on Masterpact MTZ or Schneider Electric, please visit http://www.schneider-electric.us/mtz.

About Schneider Electric

Schneider Electric is leading the Digital Transformation of Energy Management and Automation in Homes, Buildings, Data Centers, Infrastructure and Industries. With global presence in over 100 countries, Schneider is the undisputable leader in Power Management – Medium Voltage, Low Voltage and Secure Power, and in Automation Systems. We provide integrated efficiency solutions, combining energy, automation and software. In our global Ecosystem, we collaborate with the largest Partner, Integrator and Developer Community on our Open Platform to deliver real-time control and operational efficiency. We believe that great people and partners make Schneider a great company and that our commitment to Innovation, Diversity and Sustainability ensures that Life Is On everywhere, for everyone and at every moment.

www.schneider-electric.us

Original Source: https://news.thomasnet.com/fullstory/new-circuit-breaker-from-schneider-electric-features-increased-safety-requirements-40017709

Original Date: Nov 16 2018

Choosing Circuit Breakers Over Fuses

In the past fuses were the only option when it came to protecting homes, businesses, and equipment against overloaded circuits, shorts in circuits, and other faults.  With advancements in technology, circuit breakers became a popular option over the use of fuses due to the number of advantages they are able to offer.  The use of modern-day circuit breakers creates increased safety and reliability, decreased costs, and additional support for energy management initiatives.

Benefits of Using Circuit Breakers

Performance Reliability

The performance of fuses can decrease overtime.  Age increases the instances of fault, causing fuses to open even under normal conditions.  There is no way for fuses to be tested thus the current value that causes it to become faulty can never be determined.  Circuit breakers however are tested when manufactured and can be tested throughout its lifetime to ensure peak performance.

Comprehensive Protection

Circuit breakers trip circuit, breaking the electrical connection, up to a thousand times faster than fuses.  The trip capacity of a circuit breaker is greater than the equivalent fuses.  Modern day circuit breakers provide exception fault current limitations which was once only known to occur with fuses.  This function offers reliable protection while increasing the life of equipment by decreasing the aging that occurs with frequently tripped circuits.  Unlike fuses that can experience an overload even when one of multiple fuses opens, this will never occur within a circuit breaker.  When one breaker experiences an overload, the connection will be stopped immediately.

Increased Safety and Production

Replacing fuses can be risky for untrained personnel.  Fuses have exposed conductors and therefore can be quite tricky to change out.  The connections for circuit breakers are hidden, being that it is unexposed it keeps re-connecting the circuit safer for employees.  A major cause of fires within industrial settings occurs because of fuses that were incorrectly replaced.  This could include using the wrong fuse, incorrect model and/or rating, and more.   These issues are almost inconceivable when correcting a tripped connection when using a circuit breaker. The time saved is also considerable when using circuit breakers as reclosing the breaker can occur instantly which prevents production downtime.

Savings

Although the cost of a single fuse is less than the cost of a circuit breaker overall the installation and usage is less expensive.  Consider that three-phrase circuits must have three fuses.  Also, the cost of keeping extra fuses in stock.  Overall operation costs of using fuses instead of a circuit breaker are higher.

More Functionality

Circuit breakers, unlike fuses, can offer additional functions like ground fault protection.  System coordination between breakers, cascading and selectivity cannot occur when using fuses whereas circuit breakers allow for this feature.  Newer technology allows for circuit breakers to use remote controls, have alarm features, offer measurement features, and communication within your network.

J & P Electrical Company is a full-service electrical company that supplies contractors, end users, and supply houses with new surplus, quality reconditioned, and obsolete electrical equipment. We purchase a wide range of electrical equipment such as bus plugs, bud ducts, panel switches, substations, and transformers.  More information can be found at https://www.jpelectricalcompany.com

 

 

Power System Studies

Understanding the importance of a short circuit protection and coordination study and an arc flash hazard assessment.

A typical power distribution system for a large facility or campus is comprised of multiple distribution voltages and corresponding equipment. An incoming electrical service is provided by the local utility, which may consist of one or more utility circuits, in either a split-bus arrangement (the facility load is shared between circuits) or a duty/standby arrangement (one circuit carries the entire load, under normal operating scenarios). The incoming electrical service is usually at a medium voltage, which ranges between 600V-69,000V (common voltages include: 4.16kV, 12.47kV and 13.8kV). The incoming service voltage can be stepped down to a lower medium voltage or it can be distributed around the facility to electrical service spaces. The medium voltage will subsequently stepped down to a utilization voltage – 600V or 480V for motor loads or equipment and 208/120V for receptacles and lighting. At each distribution voltage, major electrical equipment will include: switchgear/switchboards, feeders, transformers, distribution panels and lighting/receptacle panels.

Tasked with managing these electrical assets, facility managers should ask the following important questions. How will my electrical power system operate during abnormal operating conditions, such as a short-circuit event? Is equipment properly rated to prevent damage and failure during a short-circuit event? What level of personal protective equipment should operators wear, when performing routine switching operations or maintenance on electrical distribution equipment? Two important power system studies can provide answers to these questions, along with other essential information: a short-circuit protection and coordination study and an arc flash
hazard assessment.

At each voltage level in a power distribution system, protective devices, including fuses, circuit breakers and protective relays, are used to protect electrical distribution equipment and the loads served. Fundamental protection consists of protection from overload scenarios, where too many amps are drawn by loads and overheating becomes an issue, and protection from instantaneous overcurrent scenarios, where large magnitude currents can damage equipment in a fraction of a second (a short-circuit event). Protective devices have to be adequately rated for both scenarios.

In the event of a short-circuit or other abnormal event, a large magnitude fault current will flow through multiple protective devices and levels of distribution, before it reaches the point of failure. The flow of current in the faulted circuit will be interrupted by the melting of a fuse or the opening of a circuit breaker. In an ideal situation, the upstream protective device closest to the point of failure will open before a higher-level protective device opens. For example, a fault in a motor should trip the circuit breaker supplying the motor, without impacting the main breaker for the entire facility. When this occurs, protective devices are said to coordinate, power interruptions are localized and disruption to the rest of the facility is minimized.

A short-circuit protection and coordination study provides a complete evaluation of a power distribution system to ensure all protective devices are rated for the available fault level (at a particular voltage) and adequately protect downstream equipment. As part of the study, time current curves (TCC), which plot the interrupting time of an overcurrent device based on a given current level, are produced. TCC plots provide a graphical illustration of the coordination between multiple protective devices at an available fault level. In the event that devices do not coordinate, adjustable protection settings may be revised or devices may be replaced, to provide an optimal level of protection and coordination.

An arc flash hazard assessment takes information produced in a short-circuit protection and coordination study and produces a safety analysis for those who will be working on an electrical power system. The primary threat to electrical workers is the risk of an arcing ground fault and the associated blast. An arcing ground fault can cause thermal burn injuries and physical trauma, due to the force of the blast and flying projectiles, which may consist of partially melted components. Key elements to the assessment include: short-circuit levels at various points in the distribution system, the clearing time associated with upstream protective devices, the distance between the worker standing in front of the equipment to the arc source within the equipment, the incident energy available (cal/cm2) and the flash protection boundary. Once the incident energy available is calculated, the appropriate level of personal protective equipment can be identified.

The flash protection boundary will identify the minimum distance from live parts, that are uninsulated or exposed, within which a person could receive a second-degree burn. While one might expect higher short circuit levels to be associated with higher levels of incident energy, this is often not the case. Lower short circuit currents can often cause an arc to burn longer, before a protective device is tripped, resulting in a higher level of available incident energy. Time delays on protective devices may be increased to provide better levels of coordination, however this may also increase incident energy levels. Consideration should be given to both the coordination of protective devices and mitigation strategies for arc flash hazards. Temporary settings (maintenance settings) can be used to reduce incident energy levels, during routine maintenance and work on electrical systems.

Short-circuit protection and coordination studies and arc flash hazard analyses are typically performed with the use of industry standard power system software and computer modelling. A detailed model of a power system is created and information on the power system, including: the incoming utility service, equipment ratings, protective devices and settings, feeder lengths, transformer sizes and motor sizes are inputted. Information is typically collected from the facility’s electrical single line diagrams, electrical drawings with the location of equipment in plan, record shop drawings from construction and data gathering from site surveys. Software programs will have a large database of protective devices, with user-defined protective settings when adjustable. This will allow the modeler to select appropriate settings or suggest alternative protective devices, to achieve better levels of device coordination. Once a model is complete, a multitude of deliverables can be produced, such as reports, TCC plots, graphical representations of a various operating scenarios, arc flash labels and information on PPE requirements. Correct information must be inputted into the power system model, to ensure automated calculations and results are accurate.

Most new construction projects and projects that involve significant modifications to electrical equipment will include the requirements for power system studies in the project specifications. This will ensure that an electrical installation is optimized, properly integrated with any existing power distribution equipment and operators have the necessary information to operate new equipment. While new projects provide the opportunity for updated studies, many facility managers inherit complex power distribution systems, which have undergone a multitude of upgrades and modifications over the years, with minimal updates to record documentation.

Upper Canada College faced these challenges when they undertook a project to update record documentation on their power system, complete with an updated short-circuit protection and coordination study and arc flash hazard analysis.

Founded in 1829, Upper Canada College (UCC) is one of Canada’s leading independent schools and is located on a 16-hectare (40-acre) campus in midtown Toronto. The campus is home to a number of academic buildings, student and staff residences and facilities. The campus receives an incoming utility service at 13.8kV and distributes power to a number of campus buildings, via a 13.8kV distribution network. Major buildings have individual main electrical rooms, where the incoming medium voltage circuit is transformed down to 600/347V and 208/120V. Low voltage distribution systems provide power to building mechanical systems, lighting, equipment and academic facilities. Power distribution systems had been modified over the years along with campus re-development and renovations in various buildings.

Chris Martins, Senior Operations Manager, Angus Consulting Management Ltd. (UCC’s Facilities Management Group) said, “We recognized the need to update record information on electrical power systems throughout the campus and this provided an excellent opportunity to complete an updated coordination study and arc flash hazard analysis.”

C2C Enertec Inc. was selected to complete the electrical audit and provide updated power system studies. Detailed site investigation work was completed over the span of several months. As-built drawings and building records, spanning several decades, were reviewed in detail. Electrical equipment, protective devices and existing settings were reviewed on site and catalogued. Site work was completed after hours, to avoid disruption to building occupants. Updated electrical single line diagrams were created and information collected on site was used to produce a detailed power system model of UCC’s electrical power systems. A short-circuit study was completed and time current curves were produced for the power distribution system. An arc flash hazard analysis was completed and a report detailing arc flash hazard levels, along with recommended personal protective equipment, was produced.

Information was consolidated in a detailed report for UCC’s operations group, arc flash labels were installed on electrical equipment throughout the campus and updated electrical single line diagrams were mounted on walls, in main electrical rooms. The updated power system studies and electrical records provide operations staff with new insight into how their power distribution system can be expected to operate, along safety requirements when working on equipment.

Steve Thuringer, Executive Director of Facilities, UCC said, “UCC’s electrical power distribution system is an essential part of campus operations. Having updated record information will go a long way in helping our staff with future maintenance work and renovation projects.”

In today’s world of integrated systems, the requirements of a reliable power supply and the need for workplace safety are an integral part of facility management. It is recommended that every facility consider having an up to date arc flash hazard assessment and short circuit protection and coordination study, for its electrical power systems. These two important power system studies help ensure equipment is properly protected, can minimize the impact of an unexpected short-circuit event and promote operator safety when working with electrical equipment. By developing detailed requirements for technical experience and deliverables, such as compliance with industry standards and the associated methods for creating power system models, a facility manager can help ensure that their service provider produces meaningful results.

As demonstrated by the successful project at Upper Canada College, undertaking power system studies provide significant insight into an existing power distribution system, which has been modified and upgraded over time.

Original Source: https://www.mromagazine.com/features/%EF%BB%BFpower-system-studies/

Original Date: Nov 12 2018

Written By:

Fact or Fiction? What Do You Believe About Reconditioned Electrical Equipment?

There are several common myths surrounding the use of reconditioned electrical equipment and components. Is it really true that with the purchase of refurbished manufacturing equipment and parts can truly save companies time and money while also meeting environment goals?  It is our goal in this installment to debunk several myths that surround the use of reconditioned equipment and parts in the work place.

It is important to note that business decisions should always be based on facts instead of myths.  Many times, myths are just handed down stories and experiences of one user that have been embellished upon throughout the years.  In order to successfully navigate and grow your company it is crucial for companies to make decisions based on facts.  When it comes to being competitive the goal is to find a solution that meets your needs.  Purchasing high quality electrical equipment and components at a reasonable price with little to no down time should be of the highest priority.

Myth #1: Original Equipment Manufacturers Are the Only Ones That Can Properly Recondition Electrical Parts and Equipment

The biggest difference between public reconditioning companies and private OEM recondition services is the inspection process they must go through to be available for resale.  This is why it is important that you only buy from reputable product reconditioning companies like J and P Electrical Company.

At J and P, you can rest knowing that we only sell the highest quality reconditioned electrical distribution equipment available.   The standards set forth by the experts at J and P are in fact more stringent than any set-in place by OEM manufacturers.  We disassemble each part, cleaning and inspecting each one, replacing parts that need to be replaced as we go along.  They are then painted with high quality paints and acrylic enamel for durability.  Equipment is reassembled and tested until it exceeds manufacturers UL certification standards.

Myth #2: Liability Concerns are Increased with the Use of Reconditioned Electrical Equipment and Parts

When you are purchasing a part does it make you feel better to know it is fresh off the line or that it has been rigorously tested over and over again to ensure its safety?  When you purchase reconditioned parts and equipment from a company like J and P you can rest assured knowing it has been tested two times over, before and after reconditioning, each and every time.  There is less liability involved in products and equipment that have gone through arduous testing.

 

J & P Electrical Company is a full-service electrical company that supplies contractors, end users, and supply houses with new surplus, quality reconditioned, and obsolete electrical equipment. We purchase a wide range of electrical equipment such as bus plugs, bud ducts, panel switches, substations, and transformers.  More information can be found at https://www.jpelectricalcompany.com

« Older posts