Serviceline Industrial Sensors
Serviceline Explosion Protection

Inductive sensor NCN3-F31K2-N4-B33-S

  • Direct mounting on standard actuators
  • ATEX & IECEX certifications
  • Usable up to SIL 2 acc. to IEC 61508
  • Weatherproof housing for outdoor applications
  • LEDs for switching state of sensor and solenoid valve
  • Plug-in terminals
  • Temperature range
    -40 ... 100 °C (-40 ... 212 °F)
  • 2 solenoid valves can be connected

NAMUR sensors must be operated with approved switch amplifiers. Please find suitable devices below:

Please note: All product-related documents, such as certificates, declarations of conformity, etc., which were issued prior to the conversion under the name Pepperl+Fuchs GmbH or Pepperl+Fuchs AG, also apply to Pepperl+Fuchs SE.

Download the complete datasheet as a PDF:

Datasheet excerpt: Technical data of  NCN3-F31K2-N4-B33-S

General specifications
Switching function2 x normally closed (NC)
Output typeNAMUR
Rated operating distance3 mm
Installationflush mountable
Assured operating distance0 ... 2.4 mm
For assured operating distance sar see Manual Functional Safety.
Actual operating distance2.7 ... 3.3 mm typ.
Actuating elementStainless steel 1.4305 / AISI 303
8.5 mm x 8.5 mm x 0.5 mm
Reduction factor rAl 0.4
Reduction factor rCu 0.4
Reduction factor r304 0.7
Reduction factor rSt37 1
Reduction factor rBrass 0.5
Output type2-wire
Nominal ratings
Nominal voltage8.2 V (Ri approx. 1 kΩ)
Switching frequency0 ... 3 kHz
Hysteresistyp. 5 %
Reverse polarity protectionreverse polarity protected
Short-circuit protectionyes
Suitable for 2:1 technologyyes , Reverse polarity protection diode not required
Current consumption
Measuring plate not detected≥ 3 mA
Measuring plate detected≤ 1 mA
Time delay before availability≤ 1.1 ms
Switching state indicatorLED, yellow
Valve status indicatorLED, yellow
Functional safety related parameters
Safety Integrity Level (SIL)SIL 2
MTTFd1730 a
Mission Time (TM)20 a
Diagnostic Coverage (DC)0 %
Valve circuit
Voltagemax. 32 V DC
Currentmax. 240 mA
Short-circuit protectionno
Reverse polarity protectionyes, with reversed output LED is out of function, therfore more power for solenoid valve
Compliance with standards and directives
Standard conformity
NAMUREN 60947-5-6:2000
IEC 60947-5-6:1999
Electromagnetic compatibilityNE 21:2007
StandardsEN IEC 60947-5-2
Approvals and certificates
IECEx approval
Equipment protection level GaIECEx TUR 17.0055X
Equipment protection level GbIECEx TUR 17.0055X
Equipment protection level MbIECEx TUR 17.0055X
ATEX approval
Equipment protection level GaTÜV 17 ATEX 8125 X
Equipment protection level GbTÜV 17 ATEX 8125 X
Equipment protection level Gc (ic)PF13CERT2895 X
UL approvalcULus Listed, General Purpose, Class 2 Power Source
Ordinary LocationE87056
Hazardous LocationE501628
Control drawing116-0455
CCC approval
Hazardous Location2020322315002305
NEPSI approval
NEPSI certificateGYJ18.1172X
Ambient conditions
Ambient temperature-40 ... 100 °C (-40 ... 212 °F)
Storage temperature-40 ... 100 °C (-40 ... 212 °F)
Mechanical specifications
Connection typescrew terminals
Connection (system side)Screw terminals, tightening torque min. 0.5 Nm
Stripped length 7 mm , M20 x 1.5 cable gland , usable thread length 13.5 mm , screw-in depth max. 13.5 mm
Core cross section (system side)rigid: 0.14 ... 2.5 mm2
flexible: 0.14 ... 1.5 mm2
flexible with core-end sleeve: 0.25 ... 1.5 mm2
Connection (valve side)4-pin, M12 x 1 socket
Core cross section (valve side)like core cross section (system side)
Housing materialrugged, translucent polycarbonate (PC) optimised for outdoor use
Housing basePC
Degree of protectionIP66 / IP67 / IP69
Tightening torque, fastening screws4 Nm ... 5 Nm
Tightening torque, housing screws≤ 2 Nm
Tightening torque of cover srews1.5 Nm
Tightening torque, cable glandM20 x 1.5 ; max. 7 Nm
Tightening torque, stopping plug1 Nm
Height53 mm
Width100 mm
Length106 mm
NoteLED switch-off
General information
Use in the hazardous areasee instruction manuals


ECLASS 13.027273901
ECLASS 12.027273901
ECLASS 11.027220501
ECLASS 10.0.127220501
ECLASS 9.027220501
ECLASS 8.027220501
ECLASS 5.127220501
ETIM 9.0EC002714
ETIM 8.0EC002714
ETIM 7.0EC002714
ETIM 6.0EC002714
ETIM 5.0EC002714
UNSPSC 12.139121550

Details: NCN3-F31K2-N4-B33-S

Product Documentation: NCN3-F31K2-N4-B33-S

Language Selection:
Safety and Security DocumentationLanguageFile TypeFile Size
Instruction manualENGPDF187 KB
ManualENGPDF1419 KB

Design / Simulation: NCN3-F31K2-N4-B33-S

Language Selection:
CADLanguageFile TypeFile Size
CAD Portal / CAD PortalALLLINK---
CAE EPLAN Data Portal / CAE EPLAN Data PortalALLLINK---

Approvals: NCN3-F31K2-N4-B33-S

Language Selection:
CertificatesCertificate No.LanguageFile TypeFile Size
Canada USA UL Hazardous LocationE501628:1:5ALLPDF411 KB
Canada USA UL Ordinary LocationUL-US-2016797-0 / UL-CA-2013375-0ALLPDF546 KB
China SITIIAS CCC Ex Certificate2020322315002305 (Trutnov)ALLPDF1914 KB
EU Pepperl+Fuchs Certificate Ex ic ATEX Category 3 GPF13CERT2895XALLPDF123 KB
EU TUV Rheinland ATEX ia 2G, 1G, 1D s. certificateTÜV 17 ATEX 8125 XALLPDF784 KB
United Kingdom CML UKEX Category I M2 UKEX Category II 2 G UKEX Category II 1 D UKEX Category II 1 GCML 21UKEX2974XALLPDF254 KB
Worldwide TUV Rheinland IECEx iaIECEx TUR 17.0055XALLLINK---
Control Drawings
Control drawing UL / Control drawing UL   ALLPDF270 KB
Declaration of Conformity
EU Declaration of Conformity (P+F) / EU-Konformitäterklärung (P+F)DOC-3894AALLPDF1248 KB
UK Declaration of Conformity (P+F)TDOC-6235_ENGENGPDF1229 KB

Associated Products: NCN3-F31K2-N4-B33-S




Valve connector, Form B on M12, 2+PE, LED, Z diode, PVC cablefa
Valve connector, Form B (Ind) on M12, 2+PE, LED, Z diode, PVC cablefa
Valve connector, Form A on M12, 2+PE, LED, Z diode, PVC cablefa

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