Allen-Bradley 700-PK400A1 B Master Control AC Relay

Allen-Bradley 700-PK400A1 B Master Control AC Relay is a four‑pole master relay cartridge from the Bulletin 700 PK family designed to centrally switch multiple AC loads behind a single control signal. It features four normally open contacts rated at 20 A each, enabling reliable, centralized control of several subcircuits, with a 120 V coil (110 V at 50 Hz or 115–120 V at 60 Hz, depending on power standard) for compatibility with common US power systems. This open-type relay is designed for DIN rail mounting, simplifying panel integration and maintenance. As a Master Control Relay, it works with master contact cartridges to coordinate multiple loads in a single control scheme, making it suitable for automated manufacturing lines, machine control applications, and processes that require synchronized energization of multiple devices behind one PK relay.