Arc Resistant Switchgear: Protecting Workers and Equipment from Arc Flash
Arc resistant switchgear is specially engineered to safeguard personnel and equipment from the dangers of electrical arcs. By incorporating features that suppress, redirect, or withstand arc energy, this type of switchgear significantly reduces the risks associated with arc flash incidents. Below is an overview of what arc flash is, how arc-resistant switchgear works, and how it ensures operational safety.
1. What Is an Arc Flash?
An arc flash is a sudden discharge of electrical energy through ionized air, usually occurring when current attempts to jump between conductors. This phenomenon releases intense heat and light, causing rapid air expansion and sometimes violent explosions.
Common causes include:
- Electrical faults or system failures
- Damaged insulation or electrical components
- Poor installation or lack of maintenance
- Human error, especially during live maintenance
Arc Resistant Switchgear To manage these hazards, arc-resistant switchgear is used to prevent, contain, or divert the effects of an arc flash away from personnel.
2. Arc Flash in Switchgear
Arc flashes within switchgear occur when electrical discharges happen inside the enclosure. This can result from:
- Opening circuit breakers or isolators under load
- Worn or degraded insulation between components
- Loose, corroded, or damaged connections
- Foreign objects or accidental contact by workers
Arc Resistant Switchgear When the risk of arc flash becomes significant, using arc-resistant switchgear is essential to protect both people and systems.
3. What Is Arc-Resistant Switchgear?
Arc-resistant switchgear is designed to shield operators from arc-related hazards. It allows safe equipment operation and maintenance by containing arc energy within the enclosure or safely venting it away.
Arc flashes can reach temperatures as high as 35,000°F, capable of melting metals instantly. The force can also cause panel rupture and flying debris. Arc-resistant switchgear is built with features such as:
- Pressure relief flaps or ducts to guide arc gases away
- Reinforced structures to withstand internal blasts
- Arc barriers and shutters to seal openings during an arc event
4. Arc Protection Methods
Arc-resistant switchgear uses various techniques to manage arc events, including:
- Arc ducts and vents to channel gases to a safe location
- Remote operation systems to avoid direct exposure
- Fast-acting breakers to quickly clear the fault
- Sturdy enclosures with thick steel and flame barriers
- Automatic shutters that close vents during faults
Additionally, Arc Resistant Switchgear workers should wear appropriate PPE—arc suits, gloves, helmets, and face shields—for extra protection during maintenance.
5. Design and Ratings
1) Switchgear Design
Arc-resistant switchgear is built to either vent arc energy inside a room or direct it outside through ducts. Flaps or baffles open under pressure, allowing gases to exit safely. Manufacturers often require minimum room height clearances to ensure safe venting.
2) Arc Ratings
Arc-resistant switchgear is tested and rated according to standards such as ANSI C37.20.7, IEEE, and UL. These tests evaluate how well a switchgear enclosure can contain and manage arc energy under specified conditions.
6. Types of Arc-Resistant Switchgear
According to ANSI C37.20.7, arc-resistant switchgear is classified into different types based on their protection scope:
- Type 1: Provides arc protection from the front only. Limited use due to its restricted protection zone.
- Type 2: Offers protection from front, sides, and rear, allowing more flexible installation.
- Type 2B: Maintains arc resistance even with the low-voltage compartment open, offering improved operator safety.
- Type 2C: The highest protection level, ensuring arc resistance between internal compartments, preventing arc transfer inside the gear.
Type 2B is the most widely used, while Type 1 is the least preferred due to its limited coverage.
7. Conclusion
Arc flashes within switchgear can lead to equipment damage, serious injury, or even fires—making them a critical safety concern. Installing arc-resistant switchgear significantly lowers these risks by containing and redirecting arc energy away from operators and essential equipment. For industries operating high-voltage systems, investing in arc-resistant solutions is essential for ensuring workplace safety and operational reliability.
Professiona Switchgear supplier and manufacturer
- Zhejiang GONGSHUN Electrical Co.,Ltd (electricgs.com), Our company was founded in the late 1990s, specializing in the production of inflatable cabinets, SF6 inflatable cabinets, and various high and low voltage complete sets of electrical equipment. It has multiple subsidiaries under its jurisdiction, including high-voltage load switch branch, high-voltage circuit breaker branch, high-voltage fuse branch, and technology development branch.Our technical expertise, comprehensive product portfolio and long-term rich experience are helping many customers in need to solve their power problems. We’re happy to help at any time. Whether you need application product advice or technical assistance, our global service team is committed to providing you with the right support. For more technical information about medium voltage earthing switch, feel free to contact us, send an email to gongshun@electric-cn.com
- Our company specializes in producing 12KV-40.5KV series high-voltage electrical products: FZN58, FLN48, FLN36, FZRN25, FZN21, FN18, ZFN16, FN12, FN8, FN7, FN5, XRNT, XRNP, VS1, ZN28, ZW8, ZW32, JN15, GN19, GN22, GN24, GN30, CLXGN15-12, HXGN □ -12, DXG-12 (L), DFW □ -12 high-voltage cable branch box, CLXGN □ -12 (SF6) series inflatable cabinet 12KV and 35KV cable accessories, etc; CLVXP-12 indoor AC high voltage fixed switchgear, CL-SIS-12 compact solid insulated ring main unit, professional assembly Schneider SC6 (SF6) series load switchgear, ABB produced SFG (SF6) series load switchgear and other series products; Distribution and agency of high-voltage load switches and inflatable cabinets produced by Schneider Electric and ABB; Siemens produces the 3AJ1 series of indoor medium voltage vacuum circuit breakers and other related products. The company has a complete range of products and has been operating safely on domestic and international power grids for a long time, receiving unanimous praise from both new and old users. Among them, multiple products such as FZRN25, FN12, FLN36-12, XRNT-12 have been exported to various countries and regions in East Asia, South Asia, Southeast Asia, Africa, and the United States.