Reliance Electric 707312-1R Communications Tap

Reliance Electric 707312-1R, also cataloged as 57C380, is a Communications Passive Tap for coaxial cabling in Reliance Electric Automax DCS systems. The module provides a tap point on the coaxial run and includes two BNC connectors for the mainline and an RS-232 female connector for diagnostics or auxiliary access. As a passive tap, it contains no active electronics and does not require power. The part is documented in automation catalogs and distributor listings as a two-BNC, RS-232 female passive tap (707312-1R / 57C380) used with coaxial cables in Automax DCS networks. Several sources note its discontinuation by the original manufacturer, though legacy units and repair parts remain available from third-party suppliers.