System Sensor COSMO-2W i4 Series 2-Wire CO/Smoke Detector with Sounder
Overview
The System Sensor COSMO-2W is a dual-sensor detector combining smoke and carbon monoxide (CO) detection in a single 2-wire device. The i4 Series configuration delivers integrated audible alarm capability through an onboard sounder, reducing installation complexity and component count on protected circuits. This detector is engineered for life safety applications requiring reliable gas and smoke monitoring across commercial, institutional, and residential properties. The COSMO-2W (sometimes searched as COSMO 2W) operates on 2-wire supervisory protocol, simplifying circuit design while maintaining full alarm and supervisory reporting to compatible fire control panels.
Key Features
- Dual-Sensor Technology: Integrated photoelectric smoke sensor and electrochemical CO sensor in a single device, eliminating the need for separate detectors
- 2-Wire Configuration: Direct connection to fire control panel without dedicated alarm relay modules, reducing wiring labor and panel I/O demand
- Integrated Sounder: Built-in audible alarm output provides local alerting without external horn modules, streamlining system architecture
- i4 Series Design: Intelligent protocol support enables advanced supervisory reporting, including device status and fault detection
- UL-Listed Certification: Complies with UL 268 (smoke detection) and UL 2075 (CO detection) standards for fire and gas safety
- Low False Alarm Rate: Dual-sensor verification logic reduces nuisance alarms from cooking smoke or environmental transients
- Addressable Compatibility: Compatible with System Sensor intelligent control panels and certified fire alarm systems supporting i4 protocol
- Tamper Detection: Built-in supervisory switches detect device removal or circuit faults, reporting to the control panel
- Standard Mounting: 4-inch conventional detector base interface allows field retrofit into existing fire alarm infrastructure
- Extended Operating Range: Operates across standard commercial temperature and humidity ranges for indoor protected spaces
Integration & Compatibility
The COSMO-2W integrates into 2-wire fire alarm loops managed by compatible System Sensor control panels or third-party UL-listed panels supporting conventional addressable protocols. The detector reports three distinct conditions to the panel: smoke alarm, CO alarm, and supervisory faults. The integrated sounder output can be independently controlled by the panel, allowing split decision logic where smoke triggers immediate alarms while CO detections initiate pre-alarm notification sequences. The device occupies a single loop address on supervisory circuits, optimizing panel capacity utilization. Wiring connections follow standard 2-wire terminal blocks (positive and negative), with optional 4-20mA analog output for CO concentration trending on compatible panels.
Package Contents
Each unit includes the COSMO-2W detector head, 4-inch mounting base, and installation hardware (screws and anchors). Terminal blocks and strain relief fittings are integrated into the base assembly. Refer to the technical documentation for detailed wiring diagrams, loop address configuration, and panel-specific integration steps.
From a systems engineering perspective, the System Sensor COSMO-2W delivers genuine operational value in retrofit and new-build fire alarm installations where space constraints or aesthetic concerns limit the number of visible devices. Consolidating smoke and CO detection into one physical unit reduces ceiling clutter while maintaining full UL compliance for both hazard classes. The onboard sounder is particularly valuable in open-plan offices and institutional buildings where dedicated horn modules create installation and maintenance overhead.
Technical Highlights:
- Dual Hazard Detection: Photoelectric smoke and electrochemical CO sensors operate independently but share a single 2-wire circuit, simplifying loop design and reducing component failure points
- Integrated Alarm Output: The onboard sounder eliminates the need for remote notification modules on the detector circuit itself, though external horns can still be added at the panel
- i4 Protocol Reporting: Advanced supervisory messages allow the control panel to distinguish smoke events from CO events and report sensor-specific faults, improving emergency response clarity
Deployment Considerations:
- Verify panel compatibility before specifying—not all conventional fire panels support the COSMO-2W's dual-sensor output format; confirm with your control panel documentation
- Position detectors away from HVAC returns and cooking areas to minimize photoelectric smoke false alarms; CO placement should follow NFPA 720 guidelines (near potential CO sources)
- Test sounder output during commissioning to confirm audible level meets occupancy requirements; some buildings may require external horns in addition to the integrated sounder
The COSMO-2W is a practical choice for integrators managing mixed-hazard properties where dual detection is required but device density must be controlled. Its proven architecture and broad panel compatibility make it a dependable workhorse on supervised fire alarm circuits.
