What's an electrical arc?

An electrical arc is when electricity flows between two points, or electrodes. The electricity travels through the air, creating a bright light and high levels of heat. In many cases, creating an electrical arc is intentional and very useful. In other situations, however, an electrical arc can be very dangerous. Learning more about what an electrical arc is, and when they can occur, is important for workplace safety. This type of event, however, can also occur at home or anywhere else that electricity is being used, so everyone should have at least a basic understanding of what one is.

Electrical Arc

While most people think of electrical arcs as a danger, they can be used safely in many different ways. In fact, many things in the workplace can rely on an electrical arc in order to complete various tasks. The most common example in most manufacturing facilities is going to be an arc welder. This uses a controlled arc to generate a massive amount of heat, which allows people to weld metal together. On a smaller level, electrical arcs are also used in lighting systems including fluorescent lighting, metal-halide lamps, and even xenon arc lamps, which have been used for movie projectors.

Unintentional Arcs

When an electrical arc is created unintentionally, however, the results can be disastrous. This is often called an arc flash and is considered one of the most dangerous events that can occur in the workplace. This is because it emits such a powerful blast of electricity, heat, and light that it can injure or kill anyone in the area. These can be caused by damaged wiring, an overloaded circuit, and other situations. Specifically, when the electricity in a system is able to find a path with less resistance than the wires it is intended to travel, an electrical arc can occur. When it does, the electricity travels from the source to whatever destination it can find. The result can be an explosion, fire, and electrocution, which is why it is so important to always take electrical arc safety seriously.

Anyone who works with high voltage equipment should use the proper personal protection equipment to minimize the risk should an arc flash occur. This will include non-conductive gloves, masks, boots, and more. If there is a significant risk of an arc flash occurring, additional PPE may be needed to remain as safe as possible.

Additional Electrical Arc facts:

  • An electric arc is a continuous, high-density electric current between two separated conductors in a gas or vapor with a relatively low potential difference, or voltage, across the conductors. Source: https://en.wikipedia.org/wiki/Electric_arc
  • An electric arc can produce temperatures up to 20,000°C, which is nearly four times hotter than the surface of the sun. Electric arcs can be used for various applications, such as welding, lighting, plasma cutting, and arc furnaces. Source: https://www.britannica.com/science/electric-arc
  • An electric arc can also be dangerous, as it can cause burns, fires, explosions, and electric shocks. To prevent or minimize the risk of electric arc injuries, workers should wear appropriate personal protective equipment (PPE), such as gloves, helmets, goggles, and flame-resistant clothing. Source: https://www.electricity-magnetism.org/what-is-an-electric-arc-and-how-can-it-be-dangerous/
  • An electric arc can be initiated by different methods, such as thermionic emission, field emission, or ionization and glow discharge. An electric arc may occur either in direct current (DC) circuits or in alternating current (AC) circuits. In the latter case, the arc may re-strike on each half cycle of the current. Source: https://www.acelectricohio.com/what-is-electrical-arcing/
  • An electric arc was first discovered by Sir Humphry Davy in 1800, when he observed a spark between two carbon rods connected to a battery. He named it an arc because it assumed the shape of an upward bow when the distance between the electrodes was not small. Source: https://en.wikipedia.org/wiki/Electric_arc

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