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Siemens ASD

Stock no. S54333-F15-A1

Stock no. S54333-F15-A1

The FDA221 series of detectors are a very early warning dual wavelength (blue and infrared) smoke detectors designed to protect small business-critical environments up to 500 m². The detector works by continually drawing air into sampling holes in a pipe network. The air is passed into a uniquely designed detection chamber where light scattering technology detects the presence of very small amounts of smoke. The FDA221 detectors can communicate directly on the FDnet/C-NET loops (with an optional FDCC221S communication interface), so there is no need for separate relay or network connections.



Operating voltage

DC 19...30 V

Operating current

150 mA nominal,
250 mA in alarm

Dimensions (W x H x D)

155 x 280 x 114 mm

Sound level

High 33 dB, medium 30 dB, low 26 dB

Operating temperature

-20...+60 °C

Relative humidity

5...95% rel. (no condensation)

Pipe length

30 m (single pipe length) 2 x 25 m (branched pipe length)

Air inlet pipe

Metric: 21 mm ID...25 mm OD

Relay outputs

3 x 2 A / 30 V

Alarm threshold

0.14...2.0 % obs/m / Info alarm, pre-alarm, fire 1 (5 sets)
6.0...20 % obs/m / fire 2 (5 sets)

Area coverage

Up to 500 m²


3 Alarm state indicators
Fault indicators
Smoke and airflow level

Communication protocol


Protection category



0.2...2.5 mm² (30 - 12 AWG)