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Safety Hazards Within the Manufacturing Industry

Manufacturing seems to be a term that covers several different companies within a wide range of industries.  With such a wide variety of businesses, manufacturing facilities have a vast number of operational and safety practices they follow.  There is a specific organization known as the Occupational Safety and Health Administration that sets forth standards and compliance regulations for manufacturing facilities to help avoid common safety issues found within the sector.

 

Even though there are several different industries that make up the manufacturing sector they share a few safety concerns including:

  • Falls

Falls are the most common accidents that occurs within the United States.  The frequency of falls makes this the number one hazard found within the workplace, especially within manufacturing facilities.  Falls represent a serious risk for workers.  They can lead to death or injury; most falls will require at least a few days off work to recover from.  It is of the utmost importance that manufacturing facilities take special precautions to avoid falls throughout their facilities.

  • Machine Guarding

Heavy machinery is operated throughout many different types of manufacturing facilities which is why it is so important that proper guarding procedures are followed to keep workers safe.  Improperly installed guards on machines presents a major hazard to the safety of employees.  To keep manufacturing workers safe while operating large scaled equipment proper safety features are installed.

  • Electrical

Even when individuals are not directly working with electricity, such as you do as an electrician or engineer, there are still plenty of electrical risks involved in manufacturing.  Many manufacturing facilities use a system of bus ducts, plugs, and shut offs to avoid industries from electrocution.  Electric panels are kept secured in manufacturing locations as well to increase safety.  Large scaled equipment is also inspected and kept up to date with the use of reconditioned electrical components on a regular basis that helps keep equipment running smoothly before a chance of failing occurs.  Standards are in place from OSHA regarding electricity to lessen the risks involved within manufacturing facilities.

  • Undertrained Employees

Employees that are not properly trained for the position they are in is a problem found not only in manufacturing.  Facilities are only as safe as the people that are working within them.  It is crucial that proper training is done regularly on all pieces of equipment that workers may encounter in your facility.  When machines are replaced or even upgraded for that matter, employee re-training should be mandatory.  Exposure to proper safety training will help keep all employees throughout the facility safe.  Practicing procedures that are in place are just as important as training.  Take the time to run regular tests involving the safety procedures to ensure that they are properly executed before it becomes vital.

Learn more about J & P Electrical Company and their vast line of new, surplus, and refurbished industrial electrical components including: circuit breakers, bus ducts, bus plugs, disconnects, fuses, panel switches, tap boxes, and transformers at www.jpelectricalcompany.com.  To contact one of our product reconditioning specialists, call 877.844.5514 today.

If circuit breakers could talk

Electrical data aids in monitoring breaker life and managing power

A circuit breaker’s useful life varies greatly, depending on many factors. The harsh conditions in a mining operation might shorten a circuit breaker’s life to mere months. But it’s not uncommon to find factories with banks of them in use for decades.

The key distinction is whether that breaker is performing properly, which can be determined through time-based testing by maintenance technicians or via the circuit breaker’s ability to test itself and report its condition. And, as long as it’s talking, why not ask the breaker for information about power usage?

Power management company Eaton has a long history in the electrical industry, explains Robert Griffin, product line manager at Eaton. “Circuit protection is part of our DNA,” he says. “We’re turning circuit breakers into something that adds more value, adds more knowledge and provides additional safety benefits. Practically everything in the electrical distribution system has a circuit breaker in it. Why not leverage that device in your system to provide power and energy data?”

Eaton’s Power Defense molded case circuit breaker (MCCB) has broken the mold by adding connectivity and intelligence to one of the most common electrical devices. The payoff is higher-level metering and predictive diagnostics in a foundational electrical-system component. Eaton’s breaker-health algorithm is designed to weigh data on multiple conditions to predict device failure before it occurs.

“Everyone within the industry wants to generate data and be able to analyze it,” says Jim Lagree, chief engineer at Eaton. “We’re not just generating data to do analytics; we’re doing the analytics within the breaker, taking it from data to actionable knowledge. A significant amount of data is being processed in the unit to say you have this much of the useful life of your breaker left.”

Griffin further explained, “We know that maintenance is critical for the safe operation of circuit breakers, and, with the advancements offered by Power Defense and the breaker-health algorithm, we can now avoid guesswork or time-based maintenance approaches and proactively know when maintenance is required.”

Bigger picture

Power Defense circuit breakers provide multiple communications options, energy metering and health algorithms that deliver data about the circuit breaker, broader power distribution system and overall energy usage. Its trip units monitor and report current, voltage, harmonics, power and energy consumption, while also providing waveforms and other information to analyze safety and power availability of the connected system.

Power Defense circuit breakers are designed to communicate what type of fault caused the breaker to trip, as well as capturing waveforms before and after the tripping event to help to diagnose system conditions. “We can go back and look at these waveforms to determine what caused the tripping, which allows technicians to restore power more quickly” explains Lagree.

Talk to me

“We’ve had communications in our circuit breakers since the early 1980s,” explains Lagree. “Whether it was serial-based or it’s now Ethernet, communication has been there. The cost has come way down, so there are more capabilities. In the old days, it was a large card that you couldn’t fit inside a circuit breaker. We’ve built in faster communications capability. In the 1980s, it took a long time to transfer all of that data. Now, it’s just in the blink of an eye. We’re adding more information and more data to analyze and tell the customer more about what’s happening with the circuit protection.”

Power Defense MCCBs offer the ability to communicate on two different channels at the same time. “One channel is a dedicated Modbus RTU for the simplest type of applications,” explains Lagree. “Then there’s a communication adaptor module with a variety of protocols, including Ethernet to Modbus TCP/IP. It also has HTML5 capability, so it can publish to a Web page. And we have Profibus. What we’re leveraging is the ability of this module to adapt in the future.” A gateway capability also is available for Modbus TCP/IP, BACnet and email notification of alarms, and it’s hardened and updated to prevent the latest cybersecurity threats.

“We’ve learned to be flexible,” says Griffin. “Whether you’re working in an automation system or you’re in another process where it might have Profibus or Profinet, it’s best to have the common-denominator capability that’s flexible enough to meet the different protocols. We can run Modbus RTU as a native system or Ethernet, or we can do Profibus. And we’ll have more modules that meet these protocols as we go along.” Furthermore, for end users that don’t make use of communications in their power systems, the Power Defense circuit breakers can still communicate critical system conditions or parameters to control systems through the use of available programmable relays. “There are one to three optional programmable relays that can be included in the circuit breaker,” says Griffin. “You can program the relay to close when the breaker reaches, let’s say, 25% of its life.” Almost 30 different alarm values can be programmed onto the relay and sent to an alarm stack light or fed into a PLC.

Added value

MCCBs provide functionality in almost all low-voltage applications, protecting devices from overloads and short circuits. Many facilities use hundreds of these devices, offering an opportunity to generate data that can be leveraged not only to monitor the breaker’s health, but to optimize energy usage. “By upgrading existing circuit breakers to Power Defense technology, you’re able to get more functionality, including metering, from the circuit breaker without adding components into the system.”

Traditional thermal magnetic breakers are designed to protect people and equipment from overcurrent or electrical overloads, but they don’t provide data on what type of fault or the magnitude, says Griffin. Power Defense circuit breakers provide more visibility into the fault, capturing a wide variety of data about the event. “On the front of the breaker, there’s a series of LED lights that can tell you what type of event it was—a short circuit fault; a ground fault; or an overload fault,” explains Griffin. “You can now go into the breaker and look at detailed information about what caused the fault, when that fault occurred and what the settings were at that time. You can troubleshoot the condition and get your system corrected faster.”

Platform edge

The Power Defense technology incorporates Eaton’s Arcflash Reduction Maintenance System and Zone Selective Interlock (ZSI) technology for advanced safety. Eaton’s Arcflash Reduction Maintenance System technology is designed to reduce dangerous incident energy levels and can be activated either locally or remotely by personnel, while ZSI helps to protect equipment by intelligently selecting faster trip times depending upon the location of the fault. The Power Defense circuit breakers enable personnel to perform ZSI system testing with visual status indication to improve productivity and provide peace of mind that systems are operating as designed.

“Arc flash hazards have been identified as one of the most dangerous occurrences in electrical power systems,” explains Lagree. “More than 10 years ago, Eaton pioneered the Arcflash Reduction System technology. It’s a dedicated circuit to trip the breaker as fast as it can. That’s the best available way to reduce the amount of energy the arc flash creates.”

ZSI has been around for quite some time, says Griffin. “With Power Defense, we provide the opportunity to test that the ZSI system is working, along with the visual indication that the system is properly connected and working,” he explains.

The Power Defense platform meets a variety of industry standards, including applicable UL, International Electrotechnical Committee (IEC), China Compulsory Certificate (CCC) and Canadian Standards Association (CSA).

Original source: https://www.controldesign.com/vendornews/2018/if-circuit-breakers-could-talk/

Original Date: Sept 5 2018

Written By: Mike Bacidore

The Basics in Wiring Electrical Disconnect Switches

Understanding how the electrical system works in your manufacturing facility is not as difficult as you may think. While it may seem like magic how the lights turn on or how the power gets to your stuff that you plug into the wall outlet. However, it is far from magical and in fact it is quite simple really. It is not a very complex system when explained.

 

There are several parts that make up your electrical service, one of the most important parts being the disconnect switch. This device is designed to instantly shut off the power to your facilities main power panel. This device is a very important part of your manufacturing electrical system and should only be used in extreme conditions.

 

How does an electrical disconnect switch work?

The basic operation of an electrical disconnect switch is simple in that it truly has only one purpose and that is to kill the power to the main power panel for your facility. All the facilities wiring goes into the main power panel and is connected to breakers that control the power inside the building. The disconnect switch sits in line between your facilities electrical meter and main power panel.

 

By turning this switch off you will instantly disconnect all power going into your location, this does not however, have any effect on your electrical service. You will continue to have power at the meter and on the feeder side of disconnect switch.  It is important to know where your electrical disconnect switch is, which is also referred to as the electrical service disconnect switch.

 

When repairs or replacement is needed it is important to find the right parts.

Due to the seriousness of the functionality of the electrical disconnect switch only trained professionals should ever open up the disconnect switch box. This is because the feeder lines going into the switch have 240v running through them and that is enough to kill a person if you are in direct contact with it. When repairs are needed, and it becomes necessary to replace the electrical disconnect switch there are several options that will be recommended.  One of the more common options in manufacturing is budget friendly reconditioned disconnect options.

 

When parts are needed you can insist on using reconditioned equipment.  Often reconditioned electrical components like the disconnect are preferred as they not only save you money but most often all the bugs that are found in new OEM parts have been worked out and fixed.

 

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

 

Hot circuit breakers and dimmer switches

I recently had a home inspector ask me how hot is too hot when it comes to circuit breakers and switches. Many home inspectors, including all of the inspectors here at Structure Tech, use infrared cameras during home inspections. These cameras can’t see through walls, but can often alert us to problems with a house that can’t be seen with the naked eye.

We frequently come across warm circuit breakers, warm dimmer switches, and even warm electrical panels during our home inspections. So how warm is too warm? It depends. I know, it’s kind of a blowhard answer, but there’s no one-size-fits-all answer.

I don’t use my infrared camera as a quantitative tool; I use it as a qualitative tool. Yeah, I know, more blowhard words. Put simply, I’m not too concerned with the exact temperatures that are displayed on my infrared camera. As a home inspector, what I’m concerned with and what I dig into are the meanings behind unexpected temperature differences, aka anomalies.

If I scan a ceiling and I find a cold spot that doesn’t make any sense, I dig into it. Maybe it’s a plumbing leak from above, or maybe it’s just a cold water line that’s touching the ceiling. That’s where a moisture meter comes in handy. Ok, I’m getting sidetracked. Let’s discuss some electrical examples.

Dimmer Switches

A properly wired, properly functioning dimmer switch can get hot to the touch. I’ve found that a 65-degree temperature rise is normal for a maxed-out dimmer. If the ambient temperature is 71 degrees and a dimmer switch is at 136 degrees, I’d be concerned, but I wouldn’t report the temperature as a problem. I would, however, take an extra minute or two to figure out how many watts the dimmer is rated for. I’d then make sure there wasn’t too much being controlled by the dimmer.

Hot dimmer switch

I wrote a whole blog post dedicated to this topic, titled Hot Dimmer Switches. Check out that post for more info on this topic. If I were to write up a problem with an overloaded dimmer switch, my report comment would say something like this:

The dimmer switch for the kitchen lights was rated for up to 600 watts, but the wattage at the lights was more than this; there were ten 65-watt bulbs on this circuit. This caused the front of the switch to get extremely hot, and creates a potential fire hazard. Have this corrected.

You’ll notice that I didn’t explain exactly how to correct this. I do this intentionally because I’m not going to do the work. This situation could be easily fixed by replacing the dimmer switch with a simple toggle switch, by installing a dimmer rated for a higher wattage, or by installing bulbs with a lower wattage. Any of those would be fine, but as the home inspector, I don’t design the repairs.

Toggle Switches

I can’t think of any good reason for a toggle switch to get hot. If I ever found a hot toggle switch, I’d call that a fire hazard and recommend repair.

Circuit breakers

When a circuit breaker has a lot of current flowing through it, it will get warm. The warm 15-amp circuit breaker shown below had a 15.6-amp hair dryer running for about 20 minutes, and it warmed up to about 17 degrees over ambient. It wasn’t especially hot, but it was definitely overloaded.

Warm circuit breaker overloaded

I’d like to say that if a circuit breaker is X-degrees over ambient, it’s a problem… but there’s just no hard and fast rule for this. I can’t say this.

If I find a warm circuit breaker, I take a logical approach. First, is there a good reason for the circuit breaker to be warm? A 240-volt appliance like an air conditioner will definitely warm up a circuit breaker while it’s operating. No problem there. The image below shows a warm circuit AC circuit, but in this case, I do care about the temperature readings. This circuit is only about 8 degrees warmer than anything else in the image. This is not a significant difference, and it makes sense.

Warm AC circuit normal

You’ll notice that there’s a single general lighting circuit that’s warmer than the other breakers in this panel; again, it’s only a small increase in temperature, so I’m not concerned. If it were much warmer, I might question why.

To take it a step further, I’d take the time to measure the amperage on the circuit. I wrote a blog post dedicated to that topic, titled Using an infrared camera to find an overloaded circuit. Many home inspectors are opposed to doing this type of test, and I say those home inspectors shouldn’t bother scanning an electrical panel. If a home inspector isn’t going to measure amperage, I don’t know how they could report on an overloaded circuit.

AFCI Circuit Breakers

Arc-Fault Circuit Interrupter (AFCI) circuit breakers run warm. This is normal, there’s nothing to report here.

Warm AFCI Breakers normal

Original Source: http://www.startribune.com/hot-circuit-breakers-and-dimmer-switches/491338261/

Original Date: Aug 21 2018

Written By: Reuben Saltzman

How Reconditioned Electrical Components Can Save Manufactures Money

If you are a manufacturer of products you know how essential it is for you to keep those operating costs down to make as much profit as possible and to see your business thrive.  One way of reducing your overhead is by purchasing those raw materials at the least expensive rates possible.

Another way of reducing those operational costs is by replacing those worn out electrical parts needed in your manufacturing equipment with quality reconditioned electrical distribution equipment and reconditioned electrical parts. Keep in mind that not all parts that need to be reconditioned have functional problems to begin with, the parts may simply have been leased and when the lease has expired the part may be returned and need to be reconditioned before being issued for sale. Reconditioned electrical parts are of similar quality as new parts, but simply cost a lot less.

As surprising as it may be, purchasing high quality reconditioned electrical parts can save your manufacturing company anywhere from 50% to 75% over purchasing new parts and when quality reconditioned electrical equipment is reconditioned properly they can last if those new parts as well.

Choosing the Right Reconditioning Company

Of course you don’t want to purchase reconditioned electrical distribution equipment from just any company that reconditions these types of parts you want to buy those reconditioned electrical parts from a company that has an excellent record for those parts they sell and you want to make sure that the company has excellent reviews from places such as the Better Business Bureau and Google as well as testimonials on the company’s website.

When purchasing reconditioned electrical parts even from a reputable company here are some things you want to know about the reconditioning process before purchasing those parts.

Here are a few of the questions you want to ask.

1) What type of electrical parts does the company recondition? Does it recondition and sell the types of parts your manufacturing company needs?

2) Does the reconditioning Company completely disassemble the use part and clean all the parts and examine them to ensure that each of the smaller individual parts are in good condition?

3) Is the reconditioned used part then repainted with quality paint to give it that new like look and help to protect the part?

4) Is the reconditioned part tested once it is put back together and does the reconditioned part meet or exceed the Manufacturers UL certification.

5) Does the reconditioned part come with some type of warranty, so you can be assured that the money spent on the used part won’t be wasted?

By purchasing high quality reconditioned electrical components manufactures can save significant amounts of money when replacing those old worn out electrical parts for you manufacturing machinery. If your company is looking to cut operating costs, then buying reconditioned electrical parts for a reputable company may be one way do so.

Learn more about J & P Electrical Company and their vast line of new, surplus, and refurbished industrial electrical components including: circuit breakers, bus ducts, bus plugs, disconnects, fuses, panel switches, tap boxes, and transformers at www.jpelectricalcompany.com.  To contact one of our product reconditioning specialists, call 877.844.5514 today.

 

 

Understanding Your Business’s Breaker Panel

Technology has been growing faster and faster in recent years, and your business seems to need to use it all to keep up with your competition.  All those computers and other technological devices that are helping your business grow are taking up more power and space in your business’s breaker panel, which can lead to trouble after a while.

That means that your breaker panel eventually may not be large enough to handle everything and you may find that your company will go in the dark every so often.  There are a few signs that you should look out for to see if it is time to replace your business’s breaker panel.  One of the most noticeable things that you will see are flickering lights.  While you may think that your light bulbs just need to be changed, the fact is that you may need a new breaker panel installed instead.

Another sign may be that your panel switches keep tripping and shutting things down.  This may not be a big deal the first time that it happens, but after a while, it can affect the productivity of your work.  You should also be able to read what each panel switch is connected to, and if you can’t then it can be difficult to know which panel switches to flip when you need to cut the power to something in your office.

Strange buzzing noises or popping sounds are never a good sign either, and anything like that can quickly cause an electrical fire to start.  You may want to try to ignore many of these signs, in hopes that you can just get by to save money, but we recommend getting these things fixed immediately.

Here at we offer for sale an abundance of reconditioned electrical surplus options.  All our reconditioned breaker panels meet the strictest safety requirements, and if it weren’t for the lower cost, you would have no idea that these units were reconditioned when you look at them.

We can find a new breaker panel that will fit your current and future needs in our reconditioned electrical surplus and install it quickly, so that your business does not experience too much downtime.  Since these breaker panels are ready to go, all we need to do is hook them up and attach everything before turning them on.  This is much cheaper than rewiring and the many other options that some other electrical companies offer.

We know that your time is valuable to your business, and we have found that using reconditioned electrical surplus items can save you that time as well as a lot of money.

Learn more about J & P Electrical Company and their vast line of new, surplus, and refurbished industrial electrical components including: circuit breakers, bus ducts, bus plugs, disconnects, fuses, panel switches, tap boxes, and transformers at www.jpelectricalcompany.com.  To contact one of our product reconditioning specialists, call 877.844.5514 today.

What to Consider for Transformer Replacement with Quick Return to Service

When it comes to power transformer replacement, a few tips can ensure a quick return to service while also reducing future costs and downtime.

When power transformers fail, the effects on plant operations can be debilitating. The production gets interrupted; everything grinds to a halt, and the effects on the bottom line can be immediate and devastating. This can put a lot of pressure on those in charge of getting operations back up to full-speed.

To make matters worse, since power transformers rarely go down, it is not uncommon for those in charge of purchasing a replacement unit to have little to no experience in the process. In addition, to someone who doesn’t purchase many transformers or know much about their design, it may seem as though transformers are more of a commodity item, and hence, can be sourced out to the lowest bid. However, there are a number of considerations that can have long term impacts.

“Quality doesn’t always increase the initial purchase price, but it can greatly reduce long-term costs in a number of important ways,” advised Alan Ober, chief engineer at Electric Service Company (ELSCO), an expert with over 40 years of experience in the design and manufacturing of transformers.

Selecting the proper transformer design and construction can actually make a huge difference by extending operating life, reducing overall costs and decreasing the need for future maintenance. The following considerations can help avoid common pitfalls in the sourcing and installation of transformers.

Selecting the Right Transformer

To maximize the return on investment on what is arguably the heart of any industrial plant it is important to understand some of the basics. Starting from the top, power transformers are required to step-down the higher voltages delivered by the electric utility company.

For indoor applications, dry-type transformers are by far the most common due in part to the fact that they are air-cooled, so they pose lower risk of problematic leakage, environmental issues and fire. Since they can safely be used inside a facility, dry-type units can be placed right next to the equipment they are powering which can further reduce costs.

In addition, a plant can save additional operational costs by selecting a new unit over a refurbished option. This is due to the higher efficiencies standards enacted by the Department of Energy in 2010 and then further tightened in 2016 on all new transformers.

Evaluate Winding Design

The way in which the coils are wound around the core of a dry-type transformer greatly affects its robustness and ability to survive “impulses” that can occur from phenomena such as switching surges and lightning strikes.

Two of the most common transformer designs today feature either circular (round-wound) or rectangular windings.

While many transformer manufacturers still offer rectangular windings, because they are less expensive to build, they can develop problematic air traps, hot spots and other problems.

The round coil design, on the other hand, provides significant ongoing operational and cost-saving advantages. Round-wound transformers stay cooler, run quieter, and present less risk of short circuit when coupled with a sheet wound secondary.

Consider the Material

In addition to the design, the material used for the windings and insulation can greatly affect performance and prevent disastrous emergencies from occurring during the unit’s operating life.

For transformer windings, the most common materials used are copper and aluminum. While copper does have a higher upfront cost, it more than makes up for that by outperforming and outlasting aluminum.

The selection of proper insulation also plays a major part in ensuring transformer reliability. Temperatures can reach 200 degrees C in a dry-type transformer on a daily basis; hence skimping on insulation can lead to disastrous consequences.

Therefore, higher-quality insulation, such as DuPont Nomex flame resistant meta-aramid insulation, should strongly be considered. This is the same insulation used in the safety gear worn by race car drivers, fire departments, military applications, as well as in numerous electrical applications.

Investigate a “Drop-in” Solution

Finally, a factor that is often overlooked: The removal of the old transformer and installation of the new one can be time-consuming and costly if not properly addressed beforehand. This is particularly important when there are existing enclosures with dimensional/clearance constraints.

Throughout his career, Ober has seen a number of situations where it has taken riggers days to complete the removal of transformers, and then several more days for the new unit to be installed and hooked up to the switchgear and bus work. Custom bus work for dry-type units may be part of the solution.

“The transformer manufacturer should be consulted and needs to be capable of slightly modifying the transformer – either new or remanufactured – so that it can be ‘dropped-in’ or mated with the existing transformer infrastructure, meeting UL, IEEE standards plus all required clearances, within a few hours,” said Ober.

He added that consulting suppliers on a user’s specific application, present and anticipated power supply needs, and getting an informed evaluation of the options available, can lead to the effective selection of a transformer that will pay substantial dividends in performance and greatly reduce the total cost of ownership.

Author: Ed Sullivan is a Los Angeles-based freelance writer with more than 30 years of expertise in the power generation and distribution industry. 

Original Source: http://hconews.com/2018/02/21/transformer-replacement/

How Are Bus Plugs and Ducts Used in Manufacturing?

All buildings whether commercial or residential require some sort of electrical power in order to provide lighting, outlets and other electrical devices. For commercial buildings, you have power needs for machinery, lighting, cooling systems, and other types of electrical needs. Typically, in a residential building, you have electrical service entering the house with cables. This is different then how electrical power is distributed in commercial and manufacturing settings.

Commercial buildings, especially those used by medium or large-scale manufacturing businesses use a larger type power distribution system that requires a much different way to run power through the manufacturing spaces of the building. Unlike residential power distribution which uses cables to carry the power throughout the home, commercial building use bus ducts or sheet metal runs with either aluminum or copper busbars.

History of the Busway Power Distribution System

The busway and bus bars were first introduced in the US back in the 1920’s at the request of the auto industry in Detroit, Michigan. The system gave them the necessary versatility that was needed for supplying power to the assembly line equipment that was being used in the manufacturing facilities at the time. Over the years since, there have been numerous innovations that have improved on the original design and installation procedures.

 

Commercial Power Distribution System Components

Heavy duty machinery typically found in manufacturing plants have unique power requirements which cannot be served by typical power distribution systems that are found in most residential homes and most commercial buildings. For these unique power requirements, there is a power system that is designed especially suited for this type of need. Bus Ducts and Bus Plugs are combined to deliver the necessary power to each machine

 

Bus Ducts – Bus Ducts also referred to as busways are sections of sheet metal with bars attached to them that are made of either aluminum or copper.  The sections are connected together in order to reach each piece of machinery that is needing the power. This type of power distribution system requires trained, certified professional electricians to install them and ensure that they are in full operation at all times.

 

Bus Plugs – Bus Plugs are specially designed components that work in tandem with the busbars in a unique type of power distribution system that is typically installed in a large-scale manufacturing facility. Each bus plug is used to connect directly to busways that are running throughout building to deliver the power to equipment like large motor starters and other power switching equipment.

Indoors and Outdoors Power System

One of the benefits of using this type of system in a manufacturing facility is that it can be used both indoors and outdoors to deliver the necessary power to different parts of any operation. The unique design of the system helps to prevent voltage drops across each of the numerous sections of the bus ducting throughout the building.

 

The system can also be fitted with a trolley system that is designed to deliver power to equipment that is designed to move frequently. There are also cables that are used to deliver the power directly to the trolley itself.

 

Learn more about J & P Electrical Company and their vast line of new, surplus, and refurbished industrial electrical components including: circuit breakers, bus ducts, bus plugs, disconnects, fuses, panel switches, tap boxes, and transformers at www.jpelectricalcompany.com.  To contact one of our product reconditioning specialists, call 877.844.5514 today.

Power supply ins and outs

While the switching power supply data sheet may document compliance to over two dozen general specifications, focusing on the input and output specifications and the safety standards that impact installation highlights some of the basics of specifying and integrating the device.

Most power supplies have the input voltage well supported with a nominal range of 85-264 Vac suitable for use with any 115- to 230-Vac supply. The typical voltage frequency range covers any 50- or 60-Hz supplies, as well.

From an integration standpoint, things start getting interesting when discussing nominal current and inrush current. It is common for the input to most power supplies to be internally fused, but adding supplementary fusing or, preferably, a miniature circuit breaker (MCB) to the input that can be turned off and on is best practice. The full load input current is noted in the data sheet and fusing between 150% to 500% of the specification, and wiring with suitable gauge wire, is appropriate. For example, when wiring 2 A to 10 A switching dc power supply, include a 10 slow-blow fuse or MCB and 16 AWG wire to protect input wiring.

From an integration standpoint, things start getting interesting when discussing nominal current and inrush current.

However, be certain that the fuse or MCB can handle the inrush current. While the inrush duration is less than half an ac cycle, it can be six to 20 times the full load input current. This can certainly trip fast-blow current protection devices, so check the manufacturer’s recommendations as slow-blow fuses and circuit breakers are likely needed.

The power supply output voltage and the nominal output current or maximum output power are likely the most important specification for the application, but there is more. From the voltage side, there is output adjustable range, overvoltage protection, voltage tolerance and ripple to consider. These output-voltage specifications can impact sensitive applications, such as analog circuits or test systems, but most 24 Vdc power supplies can deliver the needed potential.

The output current may need a closer look—specifically, nominal output current and current limit method. This includes protection against short circuit and overload. This power-supply output protection often resides internally to the device, but that doesn’t mean additional protection is not needed when integrating it.

Short-circuit protection is often built-in to the power supply and will shut off output power when a short circuit fault occurs. The input power typically will need to be cycle off to on to reset this fault.

Many power supplies use a feed-forward current limit method on the output. This limits the maximum overload current to 110%, 150% or 200% of nominal current, depending on the power supply selected. With this method and when an overload condition occurs, the current continues to rise to the limit, but the voltage drops to maintain constant power. This disrupts the constant voltage feature of a power supply but can help to start an electric motor with high inrush or power through other high-inrush events.

These feed-forward current limit events may cause devices, such as cameras, light curtain controllers or safety relays, to intermittently lose power. The switching power supplies’ built-in protection from overload can also affect the output protection methods required. Adding fuses, MCBs or electronic-circuit-protection (ECP) devices to the output circuit can help to capture and isolate the circuit causing the overcurrent by tripping the protection device.

Translated to design considerations, that means to separate high-inrush dc circuits, such as motors, from low-level circuits, such as controllers, HMIs and safety relays. Distribute the dc power output through multiple protection devices such as fast-blow, non-time-delay or slow-blow circuit breakers depending on the connected load. For even better detection of overcurrent faults, the ECP monitors both current and voltage. A prolonged undervoltage condition can help to indicate the circuit causing the problem.

Designing the dc power distribution to feed power through multiple protection devices also enables the use of smaller gauge wire. The use of smaller wire is common in discrete and analog I/O and other signal cable runs.

The discussion above regarding output short circuit and overload is related to general safety specification, met by many power supplies, for Protection Class 1 (IEC 536 or NFPA 70, Article 725). While Article 725 does cover some low-voltage industrial control, some computer networks and other remote-control, signaling and power-limited circuits, it’s as much about usage and power limitations that differentiate it from power circuits.

Class 1 discusses the portion of wiring in the power-supply circuit between the overcurrent device and the connected equipment. Class 1 circuits have a voltage requirement of less than 30 V and a power restriction of less than 168% of the device’s Volt-Amp rating, and overcurrent protection is required.

Some power supplies meet Class 2 requirements—upgraded output protection for the connected loads. This class focuses on the circuit between the Class 2 power supply and the connected equipment. It protects the circuit from fire and the personnel from electrical shock.

There are many requirements for Class 2 circuits, but wiring to the power-supply load side does not require a fuse if the proper wire is used. An example of this is power over Ethernet (PoE) cables. Without proper current limiting and wire size, 100 cables together in a bundle could cause quite a fire.

Original Source: https://www.controldesign.com/articles/2018/power-supply-ins-and-outs/

Original Author:  Dave Perkon, technical editor

Fused Disconnect Switch vs Circuit Breakers

For all those people who are looking for major differences between fused disconnect switches and circuit breakers, this post will eradicate all your confusions and help you to make the best choice. Before proceeding further, let’s shed some light on why you need devices such as circuit breaker panels and fused disconnect switches.

Electrical circuits in residential and commercial establishments are designed to carry a certain amount of current. Due to any reason, if more current passes through them, it can lead to dire circumstances where sensitive appliances and equipment can be destroyed. In some situations, this overflow of current through electrical circuits can also result in a fire that can prove to be extremely fatal for the inmates of the building.

In order to prevent such a situation from happening, different devises such are used that serve the purpose of protecting overcurrent in wires. These devices, in a current overflow situation, disconnect or open the circuit. This helps in preventing the fire from erupting. Thus, there are fewer chances of any damage to be caused to appliances and equipment installed in the building. Devices such as circuit breaker and fused disconnect switch also work in case of short-circuit situations.

Now that you are aware of the basic function of both these devices; let’s now have a look at major differences between them.

Fused Disconnect Switch

A fused disconnect switch, as the name suggests, is a combination of a fuse and switch. The fuse shuts the circuit off and switch disconnects it in case of an issue. Switches are designed to be shut the power off manually. On the other hand, fuse works in the opposite way. They are made up of a small filament that melt down in case of a current overflow. A fuse’s current rating is preset. Thus, when the current exceeds the rating of the fuse for a longer period of time it melts automatically. As a result, the circuit is disconnected.

A point to note here is that when a fuse disconnects the circuit, it can be used again. Power can only be restored if the fuse is replaced by a new one.

Circuit Breaker

With circuit breaker, there is no issue of getting a new fuse every time it turns the power off due to the overflow of current or short-circuit. Thus, it is often considered a better option for many appliances. Circuit breaker panels can also be turned off in a manual way as they also serve the functions of a switch. This feature makes them handy if you want to do get some electrical work done in the building.

A circuit breaker disconnects the circuit automatically with the help of an electromagnet it features when it detects overflow of current or a short-circuit. After the problems have been fixed, it only needs to be turned back on for restoring power.

A Final Word

To sum it up, both these devices can help a great deal to eliminate issues caused by the overflow of current or short-circuit. As stated above, a circuit breaker disconnects the circuit both automatically and manually and a fused disconnect switch offers the same purpose. The difference lies in their design and functionality. Thus, when selecting them, take into consideration the electrical requirements of your premises for taking the best decision.

Learn more about J & P Electrical Company and their vast line of new, surplus, and refurbished industrial electrical components including: circuit breakers, bus ducts, bus plugs, disconnects, fuses, panel switches, tap boxes, and transformers at www.jpelectricalcompany.com.  To contact one of our product reconditioning specialists, call 877.844.5514 today.