A-B 856T-BP1 Operator Station Component

Allen-Bradley 856T-BP1 Sound Module (often listed as “Operator Station Component”)

 

 

The Allen-Bradley 856T-BP1 is a 70 mm stack light sound (audible alarm) module, used in the 856T Control Tower signaling system. It is designed to provide an audible warning (buzzer/horn) in addition to visual stack light signals.

Although some listings call it an “operator station component,” it is actually part of an industrial signal tower (alarm system), not a control or HMI device.

Key Specifications

• Model: 856T-BP1
• Brand: Allen-Bradley (Rockwell Automation)
• Series: 856T Control Tower
• Product Type: Sound / Horn Module
• Size: 70 mm stack light system
• Sound Type:
  • Piezo electric horn
  • 8 selectable tones
• Output Level:
  • High-decibel industrial alarm (up to ~105 dB depending configuration)
• Supply Voltage:
  • 24 V AC/DC
• Mounting:
  • Top-mounted modular stack system
• Housing:
  • Black industrial polycarbonate
• Protection Rating:
  • IP66 / IP67

What it does (simple explanation)

PLC / Controller output
↓
856T-BP1 sound module
↓
Alarm horn / buzzer sound
↓
Operators hear machine status alert

It is used to:

• Warn operators of machine faults
• Indicate alarms or safety conditions
• Provide audible confirmation of machine status

Main Functions

• Produces audible alarm signals
• Supports multiple tone patterns (8 tones)
• Works with stack light visual modules
• Improves operator awareness in noisy environments
• Can be triggered by PLC or relay outputs

Key Features

• 8 selectable tones (via configuration)
• High-volume industrial sound output
• Modular design (fits 856T stack light system)
• Weatherproof IP66/IP67 protection
• LED + sound combination possible (with other modules)
• Long service life piezo technology
• Compact 70 mm tower system integration

System Role

Typical structure:

PLC / Output relay
↓
Power/base module
↓
856T-BP1 sound module
↓
Audible alarm in factory environment

So it is:

• ❌ Not a push button
• ❌ Not an HMI or operator panel
• ❌ Not a PLC module
• ✔ A stack light audible alarm module

Applications

• Machine fault alarms
• Factory production lines
• Conveyor systems
• CNC and automation machines
• Safety warning systems
• Process plant alarm indication