Redback 7 Day School Timer with Lockdown & Fire Alarm (A4505C)


A 4505C

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The Redback Timed Audio Announcement, Lockdown, and Fire Alarm Controller is a comprehensive solution housed in a convenient 1RU rack mount chassis. Perfect for scheduled announcements, the controller offers a total of 50 event switching times through its advanced timing functions. Each event can be programmed to last from 1 second up to 24 hours. When activated, an MP3 audio file is played from one of the 99 playback folders on the included micro SD card, featuring options such as bell, pre-bell, and music. Multiple MP3s in a folder are played randomly, and timing events can be programmed directly on the unit or via the included PC software. Additionally, events can trigger the Bell 24V output without audio playback.

Designed to meet industry-standard building emergency requirements, the lockdown and fire controller ensures safety by connecting to a paging system amplifier. It alerts and/or evacuates building occupants during emergencies such as fires, gas leaks, bomb scares, or earthquakes.

The lockdown, fire, bell tones, and cancel functions can be triggered by front switches, external wall plates, or rear terminal contacts for remote activation. The unit provides switched 24V DC output connections for bell, lockdown, fire, or common out, allowing connection of override relays in remote volume controls, warning strobes, bells, and more.

The timer and bell times can be managed remotely over a local area network (LAN) or virtual private network (VPN) using the A 4498 Ethernet adaptor pack.




  • MP3 Playback: Bell, pre-bell, and music timing output.
  • Emergency Tones: Conforms to AS 1670.4 standards.
  • Random MP3 Play: For pre-bell and music triggers.
  • PC-Based Setup: Easy timing event setup via software.
  • Local & Remote Triggering: Control lockdown, fire, and bell functions.
  • Touchscreen Compatibility: Connect to A4660 touchscreen paging console.
  • Voice Over Messages: Available in lockdown and fire cycles.
  • Switched 24VDC Outputs: For bell, lockdown, fire, or common out.
  • Pluggable Screw Terminal Connections: For easy installation.
  • Auxiliary Level Output: For versatile audio integration.
  • Battery Backup: Maintains current time during power outages.
  • 24V DC Operation: Reliable power source.
  • 1RU 19” Rack Case: Compact and easy to install.
  • Compatible: Suitable for any amplifier with aux input.
  • Australian Designed and Manufactured: Quality you can trust.


Upgrade your public address and emergency alert system with the Redback Timed Audio Announcement, Lockdown, and Fire Alarm Controller, designed for seamless integration and reliable performance.


  • Output Level: 0dBm
  • Distortion: 0.01%
  • Frequency Response: 140Hz - 20kHz
  • Signal to noise ratio: Lockdown/Fire/Chime - 70dB typically


Output Connectors

  • Audio Output: RCA Stereo Socket
  • Common 24V DC Out: Screw Terminals
  • Lockdown 24V DC Out: Screw Terminals
  • Fire 24V DC Out: Screw Terminals
  • Bell 24V DC Out: Screw Terminals


Please Note: Output loads limited 0.12Amp each


Input Connectors

  • 24V DC Power: Screw Terminals
  • 24V DC Power: 2.1mm DC Jack
  • Remote Lockdown, Fire, Bell, Cancel: Screw Terminals
  • Muting: Via Microphone Switch Contact



  • Lockdown/Fire: Rear Volume
  • Voice over: Rear Volume
  • Bell: Rear Volume
  • Pre-bell: Rear Volume
  • Music: Rear Volume
  • Power: On/Off Switch
  • Lockdown Switch: Illuminated Push Switch
  • Fire Switch: Illuminated Push Switch
  • Bell Switch: Illuminated Push Switch
  • Cancel Switch: Push Switch
  • Indicators: Power on, MP3 error, Pre-bell
  • MP3 File Format: 128kbps, 44.1kHz, 32bit, VBR or CBR, Stereo (even better as mono).



  • Power Supply: 24V DC
  • Dimensions: ≈482W x 175D x 44H
  • Weight: ≈2.1 kg
  • Colour: Black



*Specifications are subject to change without notice.

Redback 7 Day School Timer with Lockdown & Fire Alarm (A4505C)

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