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White rectangular sensor unit with front speaker grille and side mounting tabs

Serene Innovations

Serene Innovations SI-CA-AX CentralAlert Audio Alarm Sensor telephone accessory

SKU CH-S3W4-ZXSQ2

Audio alarm sensor detects T3 and T4 sounds, transmits wirelessly up to 200 ft to the CA360, supports ten units per system, and runs on two AA batteries for ten months

  • Detects all alarm sounds including T3 and T4 patterns
  • Hardwire option connects directly to alarm terminals for activation
  • Wireless 2.4 GHz Smart-Code signal reaches up to 200 ft open space
  • Supports up to 10 sensors per CA360 system for whole-home coverage
  • Low battery indicator warns before two AA alkalines expire after 10 months

CentralAlert Audio Alarm Sensor

The Serene Innovations SI-CA-AX is a wireless sensor designed to detect audio alarm sounds and transmit a signal to a compatible CentralAlert system. It mounts near existing smoke or carbon monoxide alarms to provide notification for users who may not hear standard alarm tones. The device operates on a 2.4 GHz Smart-Code frequency for reliable communication.

Upgrades standalone alarms to system alerts

This accessory replaces reliance on a single alarm's built-in sounder by linking it to a broader notification network. The jump is worth it when a household requires alerts in multiple rooms or needs alternative notification methods such as bed shakers or strobe lights. One CentralAlert system supports up to 10 Model CA-AX sensors for comprehensive coverage.

Check alarm compatibility and mounting location

Verify that your existing audio alarms produce standard T3 or T4 sound patterns or have connecting terminals for hardwired activation. Ensure the sensor can be placed within the 200 ft open-space operating range of the CentralAlert receiver, accounting for walls and construction materials. Confirm the operating temperature range of +10 to +30°C suits the installation environment and plan for two AA alkaline batteries.

Highlights

  • Detects all alarm sounds including T3 and T4 patterns
  • Hardwire option connects directly to alarm terminals for activation
  • Wireless 2.4 GHz Smart-Code signal reaches up to 200 ft open space
  • Supports up to 10 sensors per CA360 system for whole-home coverage
  • Low battery indicator warns before two AA alkalines expire after 10 months

Specifications

No published specifications for this item yet.

Questions about this item

Where should the sensor be positioned relative to my existing audio alarms?

Mount it next to your audio alarms so the microphone can detect T3 or T4 alarm sounds; it also has terminals for hardwired connection to alarms with output contacts.

How do I pair the sensor with the CA360 and what step is often missed?

Use the 2.4 GHz Smart-Code pairing process; the step people miss is confirming the sensor appears in the CA360 device list before relying on it.

When and how do I replace the batteries?

Two AA alkaline cells last up to 10 months; the low-battery indicator signals replacement, and the sensor operates between 10 and 30 °C.

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