Allen-Bradley 812S-AOB5 Phase Reversal Relay 3PH

Allen-Bradley 812S-AOB5 Phase Reversal Relay is a three-phase protection relay (Series A) with a dedicated relay/socket configuration, designed for industrial control panels. It monitors a three-phase power distribution and detects phase reversal, providing a clear indication or interlock in 440 V or 480 V systems rated for 50/60 Hz. The 812S-AOB5 designation identifies the model within the Allen-Bradley 812S phase protection family, and the product is listed as a Phase Reversal Relay 3PH in catalog and distributor listings. This unit is specified for use on common 440/480 VAC networks and supports both 50 Hz and 60 Hz operation, making it adaptable to regional power standards while safeguarding motors and other three-phase equipment from incorrect phase sequence. Sold as a relay/socket assembly, the 812S-AOB5 simplifies panel mounting and replacement, with distributors indicating Series A and 3PH operation for straightforward integration into existing three-phase control circuits. Its 440/480 VAC, 50/60 Hz rating aligns with common plant electrical systems.