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Adding External Signaling to an Existing MP-S Answering Station

Updated on February 19th, 2026

This guide covers how to add external signaling to an existing MP-S Answering Station by using an RY-AC or RY-AC/A relay.

AP-M Operation and Installation Instructions MP-S Instructions Adding External Signaling to an AP-M Answering Station Adding an LE Series Door or Sub Station to an AP-M Answering Station Using an LE Door or Sub Station with an MP-S Answering Station Adding External Signaling to an Existing MP-S Answering Station