The Allen-Bradley 814-BAB4 Phase Reversal Relay is a phase-sequence monitoring device used in industrial control panels to detect incorrect phase order in three-phase power and trigger a protective relay action. Identified by part number 814-BAB4 (814BAB4), this relay is part of Allen‑Bradley’s phase-protection family and is designed to protect motors and connected loads from damage caused by phase reversal. Typical applications include motor control circuits and other automation panels where reliable phase-reversal detection is essential to prevent nuisance or damaging operation.
