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Compact Fan and Filter Fan Air Flow Monitor


Air flow switch | FSW800B

Air flow switch

  • Reliable Mechanical Switch Contact
  • Small Size
  • Economical
  • Easily Installs Via Clip or Clamp
  • Versatile Fields of Application
Variable Area Flowmeters, Rotameters & Switches - View related products


The FSW800B Series air-flow monitor provides a simple but reliable alternative to indicate positive or negative air flow of fans. When properly installed and connected in series with an optical (i.e. LED) or audible signalling device, a bi-directional switch will activate an electrical contact if the air flow of the fan falls below 2.5 metres/second, thus either turning the signalling device on or off.

Contact Type: Reed/magnet contact
NC (Normally Closed): Contact open with air flow
NO (Normally Open): Contact closed with air flow
Switching Threshold of Air Flow Speed: 2.5 m/s
Hysteresis: 1 m/s fixed
Contact Resistance Includes Wire: 370 mΩ
Service Life: >100,000 cycles
Max. Switching Capacity: 10 W (resistive load)
Max. Switching Voltage: NC (AC/DC 240 V); NO (DC 60 V)
Max. Switching Current: NC (DC 500 mA); NO (DC 170 mA)
Connection: 2 x single strand 0.13mm² (AWG 26) conductors, length 500 mm, tip of stranded wire stripped/tinned 5 mm
Mounting: Attachment clamp and/or clip, or integrated in protective grill
Housing: Plastic, UL 94HB, black
Dimensions: 34 x 17.5 x 7.5 mm
Mounting Position: Air-flow monitor opening perpendicular to air flow
Operating Temperature: -20 to 50°C
Storage Temperature: -20 to 80°C
Protection Type: IP 20 (NEMA 1)
Place Order(Specify Model Number)
Part Number/ Desc.
FSW801B Star
Availability: In Stock
Air-flow switch, NC with mounting clip and clamp
FSW802B Star
Availability: In Stock
Air-flow monitor, NO with mounting clip and clamp
FSW803B Star
Availability: 1 week
Air-flow monitor, NC with 80 x 80 mm finger guard
FSW804B Star
Availability: 1 week
Air-flow monitor, NO with 80 x 80 mm finger guard
FSW807B Star
Availability: 1 week
Air-flow monitor, NC with 120 x 120 mm finger guard
FSW808B Star
Availability: 2 weeks
Air-flow monitor, NO with 120 x 120 mm finger guard
All amounts shown in EUR, GBP, or USD
Note: Comes with complete operator’s manual.
Ordering Example: (1) FSW803B Air-flow monitor, NC with 80 x 80 mm finger guard, £30.00