Industrial facilities commonly use variable-frequency drives (VFDs) to control the speed at which alternating current motors operate. Let’s examine a couple of typical scenarios commonly encountered when designing the branch-circuit short-circuit and ground-fault protection device for a low-voltage (460V, 3-phase) motor branch circuit that includes power conversion equipment (VFD).
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Motor Branch-Circuit Short-Circuit and Ground-Fault Protection for Low-Voltage Variable-Frequency Drives
Is your VFD motor branch circuit properly protected?