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This post was last edited by chenjinfeng on 2020-3-1 at 16:30. The arc flash protection and control system features a very fast response time, enabling the total fault clearance time for each compartment in the switchgear to be kept within 100ms. Therefore, before an arc fault occurs and the pressure and temperature inside the cabinet rise sharply, the arc protection system can issue a tripping command to interrupt the short-circuit current, thereby minimizing damage to the equipment and risks of injury to personnel. Function of arc protection devices: 1. Reduce or minimize the harm caused by arc light to human bodies. 2. Reduce or minimize the damage caused by arc flash short-circuit faults to the equipment. 3. Prevent the transformer from suffering damage to its dynamic stability due to faults in the nearby busbars, thereby extending its service life. 4. Reduce the time required to extinguish arc flash faults, thereby preventing damage to the station’s DC system and avoiding significant losses. 5. Reduce the downtime of equipment caused by arc flash failures, and restore power supply more quickly. Application scope of arc flash protection devices: Suitable for the protection of busbars and switching equipment at voltage levels below 110 KV. Arc flash protection is primarily used for the protection of medium and low voltage busbars within switchgear, the protection of feed cable connectors, the protection of box-type substations, and the protection of rectifier cabinets. Functions of the arc flash protection device: 1. Rapid and reliable operation: It utilizes a reliable fast algorithm that enables it to detect arc flash changes and current changes within a short time and to trigger an interrupt quickly; the time interval from fault detection to tripping is less than 7 ms, ensuring that arcs in the switchgear are extinguished within 100 ms. 2. Fully digital design: The intelligent arc protection device features a fully digital design, offering flexible configuration and high operating precision, while eliminating the risk of errors caused by knobs or other mechanical designs. 3. The protection principle is simple and rational: Based on the characteristics of arc generation, the intelligent arc protection device uses both arc and current criteria for detection; these criteria are simple and enable effective assurance of accurate operation. 4. Excellent electrical performance: The fault arc detector and connection wires are all made of high-temperature resistant, flame-retardant polymer materials, providing superior electrical isolation. The intelligent arc protection device fully meets EMC standards, ensuring the overall stability of the arc protection system as well as the reliability of its operation. 5. Comprehensive fault information recording: After a fault arc occurs and causes the device to trip, the main control unit or feeder protection unit can accurately determine which arc sensor detected the fault arc. It is also possible to record in detail the three-phase current values at the time of operation, as well as the intensity of the fault arc at that moment. 6. Multiple auxiliary protection functions: The main control unit provides not only arc protection but also additional protections such as overcurrent protection, grounding protection, and protection against circuit breaker failures. These protections serve as a logical complement to the arc protection system.