Directional overcurrent relay polarizing voltage and RCA visualized Device ANSI 67

Interactive visualization of how a directional overcurrent relay (ANSI Device 67) works. Set the RCA, X/R ratio, and faulted phase... the characteristic plane and phasor diagram update live. What it shows: → Polarizing voltage taken from the healthy phase (e.g. Vab for a C-phase fault) → How X/R shifts the faulted current angle → RCA adjustment to align Vpol with the fault current for maximum torque → Trip and No Trip zones on the directional characteristic → All three phase combinations: AB, BC, CA The maximum torque condition (legacy from electromechanical relays) is still the reference angle most numerical relays use today, typically set at 180° ± 3° (give or take depending on the relay manufacturer). This tool helps build the intuition behind it before getting into relay settings. Follow me on Social Media: FaceBook: https://www.facebook.com/profile.php?... Twitter/X: https://x.com/BibleDelgado #IntuitiveVisualRelayProtectionTools #DirectionalOvercurrent #Device67 #RelayProtection #RCA #MaximumTorque #OvercurrentRelay #SubstationEngineering