55140-3H - 55140 Series

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55140 Series Image
A small flange mount Hall effect sensor occupying only 3.22cm2 (0.500in2) board space with a choice of digital or programmable analog outputs. Available in 3-wire (voltage output) or 2-wire (current output) versions. Its case design enables screw or adhesive mounting. Capable of switching up to 28Vdc and 20mA. Available with a range of sensitivity, cable length and connector options. Ideally suited for position and limit sensing, rotation and flow measurement, commutation of brushless DC motors, angular sensing and magnetic encoding.


  • Magnetically-operated position sensor
  • Digital or programmable analog types available
  • Medium, high or programmable sensitivity options available
  • Three-wire (voltage output) or two-wire (current output) versions available
  • Vibration 50g max. @ 50 to 2,000Hz
  • Shock 150g max. @ 11ms 1/2 sine wave
  • EMC compliance to DIN 40839 (consult Littelfuse)
  • Integral reverse/over-voltage protection
  • Built-in temperature compensation


  • High switching speed up to 10kHz
  • Long life, up to 20 billion operations
  • Unaffected by harsh environments
  • Operates in static or dynamic magnetic field
  • Available with a selection of cable length and connector options


  • Position and limit switching
  • RPM measurement
  • Flow metering
  • Commutation of brushless DC motors
  • Angle sensing
  • Magnetic encoders

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