True Duct Smoke Detector with Relay Output and Analogue Output, VSD 301

• Early Smoke Detection
  • Detects smoke at an early stage using an optical obscuration method.
  • Infrared beam monitors the sensing tube for smoke particles.
• Adjustable Sensitivity
  • Sensitivity range: 3 to 25% obscurity (0.1 to 0.9 db/m).
  • Adaptable to various duct environments.
• Dust Management
  • Electronics compensate for gradual dust accumulation over weeks/months.
  • Sudden changes (e.g., water drops or dust disturbances) trigger an alarm after a short delay.
• Outputs
  • Relay Output: SPDT, 1A@24Vdc or 120 Vac for fan/damper control.
  • Analogue Output: 2-10 Vdc status signal for integration with BMS or fire alarm systems.
• Analogue Output Status Levels
  • < 2 Vdc: Sensor fault.
  • 3-7 Vdc: Normal operation.
  • 7-9 Vdc: Optics require cleaning.
  • 9.5 Vdc: Smoke alarm.
• Reset and Maintenance
  • Equipped with an external reset button for easy access.
  • Cleaning requires no removal from the duct; can be cleaned like a pair of glasses.
• Construction and Compatibility
  • Compatible with all existing fire alarm and BMS systems.
  • Includes internal calibration output for monitoring via BMS.
• Advanced Signal Processing
  • Filters disturbances like dust, background pollution, and electrical interference.
  • Signal damping for disturbance rejection; bypass available for testing.

• Relay Outputs: SPDT 1A@24Vdc or 120 Vac.
• Analogue Output: 2-10 Vdc for smoke and service alarm.
• Power Supply: 24 Vac/dc.
• Probe Length: 300 mm.

Reset: Manual reset or auto reset.

• Enhanced Safety: Detects smoke reliably in ducts, eliminating false alarms.
• Cost-Effective Maintenance: Simple cleaning process reduces lifecycle costs.
• Flexible Integration: Compatible with various alarm and building management systems.
• Robust Design: Operates effectively in polluted and industrial environments.

VSD 301:
True Duct Smoke Detector with Relay Output and Analogue Output