![]() ![]() ![]() Incident energy is reduced to less than 1 cal/cm2. AQD extinguishes Arcing faults within 6ms of arc initiation providing excellent protection against arcing thermal effects by tripping the sourcing circuit breaker(s) almost instantly. The AQD creates a three-phase to ground low-impedance parallel path for fault current to flow thus extinguishing the arc fault. An arc flash hazard is defined in NFPA 70E as a source of possible injury or damage to health associated with the release of energy caused by an electric arc. Arc Quenching Device - When protecting against arcing fault pressure effects, circuit breakers are sometimes not fast enough as the pressure wave builds up within the first 10ms of the fault.Energy Reducing Maintenance Switching (ERMS) - It allows a worker to set a circuit breaker trip unit to “no intentional delay” to reduce the clearing time while the worker is working within an arc-flash boundary.Instantaneous override that is less than the arcing current.Instantaneous trip setting less than the arcing current.However, settings must be chosen to properly protect equipment while still allowing for normal load currents and routine temporary overcurrents (e.g., motor starting current) to flow without causing a trip. The OCPD coordination study will determine whether minor adjustments in circuit breaker (or other over-current protective device) settings can lower incident energy levels. Protective Device Coordination Study - An OCPD coordination study optimizes the protective device setting for reliability and arc flash protection.Short Circuit Study will be used to determine the available fault current, which is essential for the calculation of incident energy and interrupting ratings of the equipment For a balanced symmetrical system, the fault current magnitude is balanced equally within the three phases. Short Circuit Study - A three phase bolted fault describes the condition where the three conductors are physically held together with zero impedance between them, just as if they were bolted together.Data Collection and Field verification of One Line Drawings. ![]()
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