Allen-Bradley 856T-BTR3 Binary Transistor Relay

Allen-Bradley 856T-BTR3 is the transducer sound module for the 70 mm 856T Control Tower stack-light family, designed to provide audible signaling as part of a complete visual indicator. This 24 V AC/DC device functions as the transducer component within a stack-light assembly to deliver reliable sound output in industrial environments. It supports up to 80 tones, configurable in seven stages via a DIP switch and three input signals, enabling a broad range of audible cues for status, warnings, or alarms. The speaker output is rated at 105 dB(A) at 1 meter, with a maximum of 107 dB(A) at 2,700 Hz, ensuring the signal remains audible over typical manufacturing noise. The 856T-BTR3 is specifically described as a transducer module within the Bulletin 856T lineup and is used in conjunction with other 856T modules and bases to form a configurable signaling tower. Typical applications include machine-status indication, fault alerts, and process alarms on production lines where clear audible signaling complements visual indicators.