59140-4-T - 59140 Series

Series: 59140
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

A miniature flange mount reed sensor occupying only 3.22cm2 (0.500in2) board space with a choice of normally open, normally open high-voltage, normally closed or changeover contacts. Its case design enables screw or adhesive mounting. Wires exit from top right-hand side. Also available with left-hand exit (59141 series). Capable of switching up to 265Vac/300Vdc at 10VA. Available with a range of sensitivity and cable length options. Ideally suited for position and limit sensing, security, window and door alarm systems and linear actuator applications. Functions best with the 57140 or 57141 actuator.

Note: The 57140 and 57141 actuators are sold separately.


  • Magnetically-operated proximity sensor
  • Operates through non-ferrous materials such as wood, plastic or aluminum
  • Compact size requires only 3.2cm2 board space
  • Screw-down or adhesive mounting
  • Customer-defined sensitivity
  • Choice of cable length and connector


  • Well suited for usage in high-moisture and contaminated environments
  • Reed contacts last for millions of operating cycles under micro-controller voltage and current logic-level loads
  • Simple installation and adjustment


  • Position and limit switching
  • Security
  • Linear actuators
  • Door switch

cURicon cUR_NKCR8_E61760_101218351

URicon UR_NKCR2_E61760_101218351

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pdficon Littelfuse Reed Sensors 59140 datasheet

Part # Part Description RoHS Pb-free RoHS (2015/ 863/EU) Certificate REACH (SVHC’s) Declaration Halogen Free REACH (SVHC’s)
59140-4-T-02-A 59140-4-T-02-A SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-04-F 59140-4-T-04-F SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-03-A 59140-4-T-03-A SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-01-F 59140-4-T-01-F SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-04-A 59140-4-T-04-A SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-02-F 59140-4-T-02-F SENSOR RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-03-F 59140-4-T-03-F SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
59140-4-T-01-A 59140-4-T-01-A SENS RoHS No 02/21/2019 PbFree No 02/21/2019 No
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