• Duct Detector Enclosure provides early detection of smoke in air passing through heating and ventilation (HVAC) ducts in commercial and industrial facilities. Its purpose, when used in conjunction with a Series 65 or Orbis detector, is to prevent the recirculation of smoke from a burning area to areas unaffected by the fire. Operates at air velocities from 0.5 m/s to 20 m/s for use with Series 65 or Orbis detectors Transparent cover to view detector head LED Integrated smoke test port Volt-free contacts

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