ASD - aspirating smoke detection

The optical detection technology uses two wavelengths – blue and infrared. This enables FDA221 and FDA241 to detect smaller airborne particles produced in the earliest stages of overheating or as found in open fires. By determining the size and concentration of the airborne particles, the detectors differentiate between smoke, dust and steam. This results in greater detection reliability and a high immunity to deceptive phenomena which prevents downtimes and costs caused by false alarms.

FDA221 covers an area of up to 500 m² with a programmable sensitivity range of 0.14 – 20%/m. FDA241 covers up to 800 m² with a programmable sensitivity range of 0.03 – 20%/m. The detectors offer up to three modes of operation: ultrasensitive, auto-discrimination and robust. Furthermore, an alarm threshold can be defined and programmed.

FDA241 additionally offers a programmable purge functionality as well as a programmable 4 – 20 mA remote output that is able to display smoke and airflow rate. This makes the detectors ideal for challenging applications.

FDA221 and FDA241 are designed for easy out-of-the-box installation. They can be installed directly onto the detector loop of a fire protection system from Siemens. Because all detectors and peripherals share the same loop, less cabling is needed.

The patented chamber inside the detectors was specially designed to keep dust ingress to an absolute minimum. For applications with high airborne dust concentrations a VdS-certified filter cartridge is available. The benefits include an extended product lifespan and less maintenance – even if the detectors are installed in dusty and dirty environments.