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CEUL Listed

4-20 mA Shaft Speed Sensors

  • 2-wire, loop-powered 4-20 mA analog output
  • No user calibration: works right out of the box
  • Works with shaft-mounted pulser targets (disc/wrap)
  • Rugged stainless steel M18x1 housing
  • Reverse-wiring protected
  • UL listed, Intrinsically Safe (IS) 
  • Class I, Div I (C, D) Class II, Div I (E, F, G) when
      used with an IS barrier. 

The patented ST420 detects passing magnets of a shaft-mounted pulser disc or wrap and outputs a smooth, continuous 4-20 mA analog signal in direct proportion to shaft rotation speed.

Custom speed and pulser disc/wrap PPR ST420 models are available upon request.

Optional EZ-18mm Easy Sensor Mount
(see EZ-18mm page for more details)

EZ-18mm Easy Mounting for Speed Sensors

•  Mounts directly to the tapped shaft
•  Can be used with optional Mounting Magnet  if shaft is not tapped
•  Pulser disc is included with Optional EZ-18mm
•  EZ-18mm is for Series 18, ST420 Series, and  SpeedTalker Sensors