WS28P Optical 8-Pulse Wind Speed Sensor / Cup Anemometer

Regular price $93.00 USD
Sale price $93.00 USD Regular price

Inspeed's "WS28P" Optical wind speed sensor is built with precision components to provide years of accurate weather monitoring.

Features You'll Love:

  • Wire length variants to suit different applications
  • Sapphire bearing provides exceptional sensitivity to gentle breezes and long life
  • Minimal power to operate
  • High resolution pulses at all wind speeds
  • Long life
Product Details

Inspeed's WS28P Optical Wind Speed Sensor - Cup Anemometer

Inspeed's rugged and affordable WS2 Anemometer is a high quality, Inspeed-designed, Made In America wind speed sensor a variety of options available so it will be sure to be a great fit for your application.  These options include:

  • Sensor type:  reed switch, non-contacting "infinite life" Hall chip or optical 8-pulse
  • Mounting:  vertical bracket or 1/2" tube mount
  • Rotor:  polycarbonate or metal
  • Wire length:  standard lengths or customized for you

The WS2 wind speed sensor uses either a zero power reed switch (WS2R) or a Hall chip (WS2H) as the active element, with a magnet on the shaft that causes one pulse per rotation.  (If you want 2 pulses per rotation we can do that too - let us know). There is also an 8=pulse optical option, for higher resolution at all speeds. The conversion factor from pulse rate to wind speed is in the specifications below.  This "WS28P" page is for the 8-pulse optical sensor version.  Visit the "WS2R" Reed Switch page for the reed switch anemometer or the "WS2H" Hall Sensor page for the single pulse Hall chip sensors.
The difference between them is as follows:

  • Power required:  Reed Switch:  0.  Hall Chip/Optical:  ~3mA 
  • Life:  Reed switch:  depends on voltage/current applied (lower=longer).
             Hall chip/Optical:  basically infinite
    NOTE:  the reed switch and Hall & Optical PCB are replaceable items

Battery-powered applications might be better off with a reed switch anemometer whereas the Hall chip might be a better choice for situations where power is available.

The base product has 25' of wire for the reed switch, but we offer options for 50 and 100 feet.  If you need more, or less - reach out to us - we are happy to customize.

The shaft has a Tungsten Carbide ball pressed into the end, which rides on a small sapphire.  The result is very low friction - for low wind speed sensitivity, and basically zero wear - for long life.

The polycarbonate rotor is designed by Inspeed based on years of experience with some tough users (mainly storm chasers!). It is light and strong - to give you years of dependable service.  If you prefer a metal rotor, we can do that too.

The mounting bracket can be attached to just about anything so it is easy to get up and running.  the single-screw mount to the head means that you can pivot the head relative to the bracket if you need to make fine adjustments to make the rotor completely level.  Alternatively we offer a tube mount base so it can be mounted to a 1/2" tube (available separately from Inspeed or customer-provided).

NOTE:  the only options listed below are for wire length.  We can also do metal cups, tube mount, and custom wire lengths; contact us if any of these items are of interest to you.

The Inspeed WS28P anemometer is based on simplicity, ruggedness, and a commitment to precision and accuracy.


Speed Range

~3 mph to 200 mph (~5 kph to over 200 kph)

Mounting Bracket

  • Supplied with an aluminum mounting bracket with 2 holes for screws.
  • Made from 1/8" x 1/2" aluminum bar stock
  • Designed to be mounted on top of a pole or other bracket.
  • Vertical bracket for anemometers/vanes, offset bracket for the E-Vane
  • Custom brackets available up request
  • Single screw head mounting means the bracket can be tilted to keep the head horizontal

Rotor Diameter

~6 in (150 mm)


  • Standard length is 25 feet (8m)
  • Additional options include 50 ft (15 m) and 100 ft (30 m) or more
  • Custom lengths available upon request - tested OK to over 1,500 feet
  • The wire is provided stripped and unterminated (except FlexWire and Mag Mount which have jack connections)
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