Serviceline Industrial Sensors
Serviceline Explosion Protection

Float Switch LFL1-*K-N-*****

  • Switch element: float switch with initiator, mercury-free
  • Electrical connections in acc. with NAMUR for hazardous area
  • Limit value detection for fluids
  • Sleeve design: small diameter, mounting through G1 tap hole possible
  • Ball design: high buoyancy

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  LFL1-*K-N-*****

General specifications
Construction typeInductive sensor with switching ball
Rated voltage8.2 V ± 2 V
Current consumption< 1.0 mA unswitched (de-energized at the bottom),
> 2.2 mA switched (floated up at the top)
Reverse polarity protectionyes
ConnectionNAMUR acc. to EN 60947-5-6 , 2-wire
Directive conformity
Electromagnetic compatibility
Directive 2014/30/EUEN 60947-5-2:2007+A1:2012
Degree of protectionIEC 60529:2001
Function and system design
Equipment architectureA measuring system consists of a float switch LFL1-**-N and a transformer isolated barrier,
e. g. KFD2-SR2-Ex1.W.
Operating conditions
Installation conditions
Installation instructionsrange of application and minimum length between mounting and float:
- PVC version: ≥ 50 mm (2 inch), preferred for water
- PUR version: ≥ 100 mm (4 inch), preferred for fuels, heating oils, oily fluids
- CSM/CM version: ≥ 100 mm (4 inch), preferred for many acids and lyes

- The float switch is mounted either from sidewards through a cable gland ≥ G1A into the vessel or
- by means of a counter weight or rods (e. g. float switch combination) from the top.
The pivot of the cable should always be horizontal.
Process conditions
Process pressure (static pressure)sleeve design: ≤ 3 bar at 20 °C (68 °F)
ball design: ≤ 2 bar at 20 °C (68 °F)
Densitysleeve design: ≥ 0.8 g/cm3
ball design: ≥ 0.6 g/cm3
Ambient conditions
Ambient temperature-20 ... 70 °C (-4 ... 158 °F)
Storage temperature-25 ... 70 °C (-13 ... 158 °F)
Altitude≤ 2000 m above MSL
Mechanical specifications
Degree of protectionIP68
Data for application in connection with hazardous areas
EU-type examination certificateTÜV 99 ATEX 1407
MarkingEx-Hexagon II 2G Ex ia IIB T5 Gb
Directive conformity
Directive 2014/34/EUEN 60079-0:2012+A11:2013 , EN 60079-11:2012
Mechanical construction
Materialfloat: PP (Polypropylene)
- PVC version: PVC cable, highly flexible (2 x 0.75 mm2)
- PUR version: PUR cable, highly flexible (2 x 0.50 mm2)
- CSM/CM version: CSM/CM cable (chlorinated polyethylene, (2 x 0.75 mm2))
Switching pointswitch angle, measured against the horizontal:
- upper switch point +15° ±5°
- lower switch point -15° ±5°
General information
Supplementary informationObserve the certificates, declarations of conformity, instruction manuals, and manuals where applicable. For information see
Designation- LFL-Z231, counter nut, G1A, PVC
- LFL-Z32, counter weight, grey cast iron with plastic coating (Polycarbonate)
- LFL-Z33, counter weight, grey cast iron with ECTFE coating (Halar)
- LFL-Z131, gland screw connection G1A, PVC
- LFL-Z132, gland screw connection G1A, brass
- LFL-Z161, gland screw connection G2A, PVC
- LFL-Z431, gland screw connection 1 NPT, PVC
- LFL-Z461, gland screw connection 2 NPT, PVC


ECLASS 13.027200510
ECLASS 12.027200510
ECLASS 11.027200510
ECLASS 10.0.127200510
ECLASS 9.027200510
ECLASS 8.027200510
ECLASS 5.127200510
ETIM 9.0EC011178
ETIM 8.0EC011178
ETIM 7.0EC011178
ETIM 6.0EC001447
ETIM 5.0EC001447
UNSPSC 12.141111950

Details: LFL1-*K-N-*****


The initiator (NC contact) is integrated in a PP float and is activated in the event of deviations from the horizontal position. The switching ball in the float, which moves along an axis, activates the switching event in the initiator inductively. The switch output provided by the initiator is a switch signal in accordance with EN 60947-5-6 (NAMUR).

Product Documentation: LFL1-*K-N-*****

Language Selection:
Safety and Security DocumentationLanguageFile TypeFile Size
Instruction manualENGPDF131 KB

Design / Simulation: LFL1-*K-N-*****

Language Selection:
CADLanguageFile TypeFile Size

Approvals: LFL1-*K-N-*****

Language Selection:
CertificatesCert No.LanguageFile TypeFile Size
Europe TUV Nord ATEX Category 2 GTÜV 99 ATEX 1407ALLPDF3475 KB
Declaration of Conformity
EU Declaration of Conformity (P+F) / EU-Konformitäterklärung (P+F)DOC-0580DALLPDF131 KB
Contamination Declaration
Contamination declaration / Kontaminationserklärung   ALLPDF137 KB