Details

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AUDAC ARU204 Multi-Channel Digital Relay Unit – 4 Relay AV Control Module

Product Introduction

The AUDAC ARU204 is a professional 4-channel digital relay control unit designed for smart AV system integration, signal switching and automation applications. Compatible with AUDAC Touch™, the ARU204 provides flexible control through TCP/IP, RS-485, HTML5 web interface, dry contact inputs and external control devices.

Featuring four double-pole relays with Normally Open (NO) and Normally Closed (NC) contacts, the ARU204 can be used to switch various signal types, including balanced mono audio, unbalanced stereo audio, amplified loudspeaker signals, 100V distributed audio systems and voltage distribution.

Its compact DIN rail mounting design makes it ideal for installation inside electrical cabinets, AV racks and professional control systems.

Product Description

The AUDAC ARU204 Multi-Channel Digital Relay Unit provides a versatile solution for professional audio, commercial AV and automation installations requiring reliable relay switching and remote control.

Four integrated bipolar relays allow the ARU204 to perform a wide variety of switching tasks. Applications can include audio source switching, signal routing, loudspeaker line switching, equipment activation and customised AV automation.

The ARU204 offers several control methods. Users can operate the relays remotely through its integrated HTML5 web interface, AUDAC Touch™, TCP/IP network commands or RS-485 communication. Relay activation can also be triggered manually through dry contact inputs, making integration with external buttons, switches, alarm systems and other control devices possible.

Dry contact triggering takes priority over digital commands, which is particularly useful in applications where an external alarm, emergency contact or physical switch must override normal system operation.

For larger AV installations, multiple ARU20x relay units can be integrated into the same system using RS-485 communication, while TCP/IP connectivity enables integration into Ethernet-based control and automation networks.

The ARU204 supports switching of a broad range of signals, from line-level audio and low-impedance loudspeaker signals to 100V speaker lines and voltage distribution up to 240V AC, providing system integrators with greater flexibility when designing automated AV environments.

Its compact black ABS enclosure features a rear spring mounting mechanism for quick installation onto standard DIN rails. With a 24V DC power requirement and optional PSD24x external power supply, the ARU204 can be neatly integrated into professional AV and electrical cabinets.

Key Features

• 4-channel digital relay control unit for professional AV and automation systems
• Fully compatible with AUDAC Touch™
• Integrated HTML5 remote-control web interface
• TCP/IP and RS-485 control for flexible system integration
• Four double-pole relays
• Normally Open (NO) and Normally Closed (NC) relay contacts
• Supports pre-programmed timed relay triggering
• Dry contact inputs for external buttons, switches and alarm contacts
• Dry contact activation has priority over digital relay commands
• Suitable for switching balanced mono audio signals
• Supports unbalanced stereo audio signal switching
• Capable of switching low-impedance and 100V loudspeaker signals
• Supports voltage distribution applications up to 240V AC
• Multiple ARU20x units can be integrated into larger control systems
• Up to 300 m maximum cable length
• Uses standard UTP CAT5E cabling
• RJ45 Ethernet connection
• Terminal block connections for signal inputs and outputs
• Compact DIN rail mounting enclosure
• Durable black ABS construction
• Low maximum power consumption of 6W
• Operates from 24V DC
• Optional PSD24x external power supply
• Compact dimensions of 107 × 87.5 × 54 mm
• Lightweight design at approximately 0.2 kg

AV Solutions & Applications

The AUDAC ARU204 is designed for installations where AV equipment, audio signals or external devices need to be switched, triggered or automated from a central control platform.

Audio Source & Signal Switching
Use the ARU204 to switch between different audio sources or route audio signals according to system requirements. Its double-pole relay architecture supports both balanced mono and unbalanced stereo applications.

100V & Loudspeaker Line Control
The relay system can be used for switching amplified loudspeaker signals, including low-impedance and 100V distributed audio systems. This makes the ARU204 useful for commercial audio installations requiring controlled speaker-zone or signal switching.

AUDAC Touch™ Automation
Integration with AUDAC Touch™ allows relay functions to become part of a central AV control interface. Users can create a more convenient system where audio and relay-controlled functions are managed from one platform.

Meeting Rooms & Corporate AV
The ARU204 can help automate equipment and signal switching in meeting rooms, conference rooms, training facilities and corporate AV environments.

Retail, Restaurants & Hospitality
For shops, restaurants, cafés and hotels, the ARU204 provides a compact way to integrate audio switching and external device control into a centralised AV system.

Alarm & External Contact Integration
Dry contact inputs allow external alarm contacts, buttons and switches to trigger relay functions. This is particularly useful when specific external events need priority over standard digital control commands.

Large Multi-Zone AV Systems
Multiple ARU20x units can be incorporated into larger installations through RS-485 communication, making the system scalable for projects requiring additional relay-controlled functions.

Smart Building & AV Automation
With TCP/IP control and an available command set, the ARU204 can be integrated with compatible third-party Ethernet-based control and automation platforms for customised AV system operation.

Why Choose AUDAC ARU204?

The AUDAC ARU204 4-Relay Digital Control Unit combines AV signal switching, relay automation, network control and AUDAC Touch™ integration in one compact DIN rail device.

It is particularly suitable for AV system integrators, commercial audio installations, smart buildings, meeting rooms, retail outlets, restaurants, hotels, educational facilities and multi-zone audio systems where reliable and flexible relay control is required.