ST-ACR2

RDL ST-ACR2 - Line-Level Audio Controlled Relay with Adjustable Delay

The RDL ST-ACR2 is a compact audio-controlled relay module designed for automation in professional AV systems. It detects the presence of line-level audio signals and activates a relay, enabling control of other devices or system functions. With adjustable input sensitivity and release delay, the ST-ACR2 can be tailored for silence detection, source switching, or other audio-triggered actions.

The module features double-pole-double-throw (DPDT) switching contacts, an open-collector SLAVE output for external control, and a threshold LED for precise sensitivity adjustment. As part of the STICK-ON® series, it offers fast installation and reliable performance in fixed installations.

Functionality

• Detects line-level audio signal presence
• Automatically switches relay based on audio input
• Adjustable sensitivity: -30 dBu to 0 dBu
• Adjustable release delay: 5 to 50 seconds
• LED threshold indicator - simplifies setup
• Open-collector output - drives SLAVE devices
• Compact STICK-ON® format - easy integration

Features

• Audio input: 10 kΩ balanced bridging (can be unbalanced)
• Input sensitivity: adjustable from -30 dBu to 0 dBu
• Relay release delay: 5 - 50 s (adjustable)
• Retrigger delay: 250 ms
• Activation response time: 25 ms
• Relay contacts: DPDT
• Max switching power: 60 W / 125 VA
• Max switching voltage: 220 V DC / 250 V AC
• Max switching current: 2 A
• Control output: open-collector, 25 mA
• Indicator: audio threshold LED
• Power: 24 V DC
• Operating temperature: 0°C - 55°C

RDL ST-ACR2 is a reliable solution for AV professionals needing automated control based on audio signal detection.