Under What Circumstances Does an Arc Flash Occur?

By R.W. Hurst, Editor

Arc flash incidents are among the most dangerous hazards in electrical systems, posing severe risks to personnel and equipment. Understanding the circumstances under which these accidents occur is crucial for mitigating risks and ensuring safety. This article explores various factors that contribute to arc flash events, including human error, environmental conditions, equipment age, and specific types of equipment prone to causing such incidents.

An arc flash event is a dangerous electrical hazard that can have devastating consequences, including severe injuries and fatalities. It's a sudden release of electrical energy through the air, resulting in an electrical arc with intense heat and light. Understanding the factors that lead to these incidents is crucial for prevention and safety.

Under what circumstances does an arc flash occur?

An arcing fault is the most common cause of an arc flash event. This occurs when an electrical current deviates from its intended path, often due to insulation failure, damaged equipment, or accidental contact with live conductors. When this current passes through the air, it creates an electrical arc, the primary component of an arc flash event.

High voltages greatly increase the risk of an arc flash, as they possess more energy capable of initiating and sustaining an arc. Electrical systems operating at high voltages demand strict adherence to safety protocols and specialized protective equipment.

High Voltages and Faulty Electrical Equipment:
- High voltage systems are particularly susceptible to arcing faults, where a fault occurs that allows current to travel through the air. Faulty or improperly maintained electrical equipment can create conditions conducive to these events.
Installation and Maintenance Issues:
- Accidents occur when electrical equipment is not properly installed or maintained. Loose connections, worn insulation, or damaged components can create pathways for electrical arcs.
Lack of Protectant Devices:
- Without adequate protectant devices, such as circuit breakers and fuses, electrical systems are at higher risk. These devices are designed to interrupt the flow of electricity during a fault, preventing arcs.

How Does Human Error Contribute to Arc Flash Incidents?

Human error plays a significant role in many arc flash incidents. Inadequate training, improper use of tools, failure to follow lockout tagout procedures, and neglecting the use of personal protective equipment (PPE) can all lead to an arcing fault and subsequent arc flash.Several ways in which human mistakes can lead to incidents include:

Inadequate Training and Safety Procedures:
- Personnel who are not properly trained in NFPA 70E standards and lockout/tagout procedures are more likely to make mistakes that lead to arcing faults.
Improper Use of Personal Protective Equipment (PPE):
- Failure to wear the appropriate PPE can increase the severity of injuries when accidents occur. Proper use of PPE is essential for protecting workers from the hazards of electrical arcs.
Errors During Maintenance and Testing:
- Mistakes made while testing equipment or performing maintenance, such as using the wrong test equipment or failing to de-energize circuits, can create dangerous conditions.

Can Environmental Conditions Lead to an Arc Flash?

While less frequent, environmental conditions can contribute to arc flash risks. Dust, debris, or moisture accumulation within electrical equipment can compromise insulation and increase the likelihood of an arcing fault. Similarly, corrosive environments can degrade equipment over time, making it more susceptible to electrical failures. Conditions that can lead to increased risk include:

Moisture and Humidity:
- Moisture can degrade insulation and create conductive paths for electrical discharges. High humidity levels increase the likelihood of condensation, which can lead to an arc flash event.
Dust and Contaminants:
- Dust and other contaminants can accumulate on electrical equipment, creating conductive bridges that facilitate arcing faults.
Corrosive Environments:
- Corrosive substances can damage equipment over time, leading to faults. Environments with high levels of corrosive gases or chemicals require special protective measures.

What Role Does Equipment Age and Condition Play in Arc Flash Incidents?

Aging electrical equipment and systems are more prone to insulation breakdown and other failures that can lead to an arcing fault. Regular inspection, maintenance, and testing are essential for mitigating this risk. Properly installed protective devices, such as circuit breakers, can quickly interrupt the flow of electricity in the event of an arcing fault, minimizing the severity of an arc flash. Factors include:

Aging Infrastructure:
- Older electrical systems may not meet current safety standards. As equipment ages, it is more prone to failures that can lead to electrical arcs.
Lack of Regular Maintenance:
- Regular inspections and maintenance are essential for identifying and addressing potential issues before they lead to incidents. Neglected equipment is more likely to fail and cause accidents.
Outdated Technology:
- Older equipment may lack modern safety features, such as advanced protectant devices. Upgrading to newer technology can reduce the risk of arcing faults.

Are There Specific Types of Equipment More Prone to Causing Arc Flashes?

Certain types of electrical equipment carry a higher risk of arc flash due to their design and function. Switchgear, panelboards, transformers, and motor control centers are examples of equipment where arc flash incidents are more prevalent. Workers interacting with these types of equipment should exercise extreme caution and follow established safety procedures. These include:

Switchgear and Circuit Breakers:
- Switchgear and circuit breakers are critical components in electrical systems, but they can be sources of electrical arcs if not properly maintained or if they malfunction.
Transformers:
- Transformers, which step up or step down voltage levels, can experience faults that lead to arcs, especially if they are not regularly inspected and maintained.
Control Panels and MCCs:
- Motor Control Centers (MCCs) and control panels, which house various electrical controls, are common sites for arcing faults due to the complexity and concentration of electrical components.

NFPA 70E, the Standard for Electrical Safety in the Workplace, provides comprehensive guidelines for assessing arc flash risks, selecting appropriate PPE, establishing safe work practices, and conducting employee training. Adherence to these safety standards is paramount for preventing accidents that occur and protecting workers from the devastating effects of arc flash events.

Understanding the various factors that contribute to arc flash events is essential for mitigating risks and ensuring the safety of personnel and equipment. By adhering to safety standards such as NFPA 70E, properly maintaining electrical systems, and using appropriate personal protective equipment, the likelihood of these dangerous incidents can be significantly reduced. Regular training, inspections, and updates to infrastructure are critical components of an effective safety program aimed at preventing electrical arcs.

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Evluma Launches Line of Post Top Globes to Complement LED OmniMax

March 12, 2020, Renton, WA…Street and area lighting manufacturer Evluma, announces the release of a new globe accessory line, OmniMax Lighting Solutions (OLS) to complement their OmniMax family of LED replacement lamps. OLS is a custom, curated selection of spherical and acorn style globes for decorative streetlights. The OmniMax is a Bluetooth-connected, screw-in replacement lamp for use in decorative post top globe and acorn lights. The release of a globe line to complement the OmniMax is designed to make the HID to LED conversion and maintenance process easier for Evluma customers.

Customers executing a retrofit project can conveniently purchase a replacement globe at the same time they purchase the OmniMax. “The wide variety of styles and materials offered means that we can typically provide a customer with a globe that matches an older style,” said Marketing Director, Cathleen Shattuck. “Customers can refresh globes simultaneously with OmniMax installation to save on labor, or if they suddenly discover damage to individual light fixtures, we can quickly provide them with a solution. Our high level of customer service means we are well-adapted to quick turnaround on orders of any size, keeping the process convenient and low cost.”

Using OmniMax, municipalities, utilities and electric departments converting post top fixtures from HID to LED can do so in under 5 minutes a fixture. The OmniMax is available in both Premium and Standard models. Premium models are Bluetooth-enabled and are compatible with Evluma’s wireless control application, ConnectLED. Both models carry a ten-year warranty and offer Evluma’s signature low-glare illumination.

About Evluma

Formed in 2008, Evluma is committed to developing affordable, long-lasting and environmentally low-impact LED lighting solutions that fundamentally change the landscape of the outdoor utility lighting market. Evluma’s high standard of customer service and background in innovative lighting technologies, automation and software design creatively ideate and inform its utility-grade products. Evluma is located in Renton, WA, USA.

09/24/20

Evluma's Build-Your-Own Acorn is an Affordable Answer to Decorative Streetlight LED Upgrades

Street and area light manufacturer Evluma announces the release of Build-Your-Own Acorn; a full-fixture, decorative streetlight replacement solution that includes the customer’s choice of acorn globe, finial and capital fitter. This solution is designed for utilities, municipalities, facilities and property managers looking to upgrade their existing decorative lighting from HID to LED and features the OmniMax™ LED lamp as its light source.

“Build-Your-Own-Acorn is a tailored solution that puts control in the hands of the customer,” said Evluma Product Manager Jason Dobbs. “With the value-driven OmniMax at the center of quality, cost-effective options, this is an affordable approach to complete head replacements. Build-Your-Own-Acorn offers the freedom to replace and repair fixtures without being locked into a proprietary OEM solution that may be hard to change later and typically costs more. It’s everything but the pole.”

Build-Your-Own Acorn includes multiple styles of acrylic and polycarbonate globes, in addition to a cast aluminum capital fitter. The capital fits 3 inch and 4 inch poles and is offered in black or green. The 70W OmniMax LED lamp is offered in six different color temperatures ranging from 2000K-5000K in either the Premium or Standard. OmniMax Premium includes Evluma’s patented, maintenance-saving Photocontrol Failsafe™ and compatibility with Evluma’s Bluetooth lighting app ConnectLED™. OmniMax Standard ships without connectivity features or Photocontrol Failsafe built-in.

“Photocontrol Failsafe means never having to replace a failed photocontrol ever again,” said Janine Soper, Evluma’s Regional Sales Manager. “With ConnectLED, the OmniMax Premium can be quickly dimmed or programmed with a dimming schedule, offering additional aesthetic and energy saving opportunities,” said Janine.

Both OmniMax models are supported by robust 20kV/10kA surge protection and the OmniMax’s four layers of thermal management for extended operation in enclosed environments. The capital has a 5 year warranty on the finish. Acrylic globes are warrantied for 5 years against yellowing. The OmniMax and all electronics, including the capital’s optional photocontrol are warrantied for 10 years.

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Parallel Resonant AC Test Sets

High Voltage, Inc. is an American test equipment manufacturing company located in rural Copake, NY. We are known for high quality, easy to use equipment and for our commitment to providing the best customer and product support in the industry.

As we matured we expanded into larger products. Cable fault locators (thumpers) as well as higher power ac (HPA) dielectric testers as might be used in a factory environment. Our HPA line of ac testers are available with outputs up to 300 kV ac and power levels up to 40 kVA and can be customized with various levels of control sophistication.

Our new PAR line of ac dielectric testers are designed to meet the needs of those who need power levels up to 250 kVA, to be able to test their highly capacitive test loads. Using ac resonant technology outputs of 50 kV at 5A (for example) are possible with an input of only 230 v, 90 A. That is an input of 20 kVA for an output of 250 kVA. (Model PAR-50250FC5)

The PAR models consist of a control section and a high voltage section. While large, they are transportable by van or trailer for field work. The control section includes the input breaker, variable (motorized) input control, a PLC controller, and connections for controlling the hv section. The high voltage section is a steel tank with a phenolic output bushing. Inside this tank is a variable-core reactor in an insulating oil bath with an air space at the top to allow for thermal expansion.

The variable reactor looks similar to a transformer but has a moveable core that allows the inductance value to vary to match the capacitance of the load, thereby achieving resonance. This effectively cancels the load capacitance, as far as input power requirements are concerned. Once in resonance, the input voltage is increased until the desired output voltage level is achieved. For a capacitive load that must be tested at power frequency the PAR reduces power requirements, as well as test equipment size by one tenth to one thirtieth, compared to a test transformer.

The HVI PAR family of resonant as dielectric testers are perfect for power frequency testing of power cables, rotating machinery, bushings, instrument transformers, transformers, shunt reactors, and many other products.

For more info please contact sales@hvinc.com to discuss your application.
For more information on these and other high voltage test products, contact High Voltage, Inc. at www.hvinc.com, sales@hvinc.com, or call 518-329-3275.

03/07/22

Evluma Launches Low-Glare LED Roadway Luminaire

LED lighting manufacturer Evluma announces the launch of a new roadway lighting product RoadMaxTM. The RoadMax series will include three sizes: small, medium and large and a range of wattages designed to replace legacy HID 100w, 250w and 400w cobraheads. The first model in the series, the RoadMax RX1, with wattages ranging from 30W-70W and an estimated output range of 3,000 to 9,000 lumens, is estimated to start shipping at the end of April 2022.

This sleek and stylish luminaire was designed with RP-8-18 roadway requirements in mind. The unique optical design offers a combination of roadway performance and glare control unprecedented in the industry. “RoadMax is an advancement of Evluma’s reputation for low-glare, visually-pleasing outdoor lighting,” says Taisha Bezzo, National Sales Director. “RoadMax addresses contemporary concerns regarding disability glare and light trespass from roadway lighting while maintaining exceptional pole spacing.”

Multiple luminaire configurations for Type II, Type III and Type V, all with zero-uplight (U0), are offered. Additional features such as a field adjustable wattage selector (FAO), light trespass shields and a choice of photocontrol sockets are available. RoadMax can be customized to include Evluma’s Photocontrol FailsafeTM, a patented technology that solves photocontrol failures on street and area lights. Compatibility with ConnectLEDTM, Evluma’s Bluetooth app for wireless lighting controls, enables dimming and dimming schedules without the need for a network. Evluma’s comprehensive 10-year warranty and signature 20kV/10kA surge protection comes standard with every model.