Serviceline Industrial Sensors
Serviceline Explosion Protection

Float Switch LFL3-**-U

  • Switch element: mercury (Hg)
  • 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  LFL3-**-U

General specifications
Electrical specifications
Contact loading230 V AC/3 A/200 VA; 150 V DC/3 A/100 W resistive load
Rated insulation voltage300 V
Pulse withstand voltage4 kV
Directive conformity
Low voltage
Directive 2014/35/EUEN 60947-5-1:2004 + Cor.:2005 + A1:2009
Degree of protectionIEC 60529:2001
Descriptionmercury (Hg) change-over contact
Function and system design
Equipment architectureThis device may be used with any sequential circuit, as long as the circuit can support the electrical circuit values of the switching elements.
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
- TPK 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 temperaturePVC version: 5 ... 70 °C (41 ... 158 °F)
PUR version: 5 ... 70 °C (41 ... 158 °F)
CSM/CM version: -20 ... 70 °C (-4 ... 158 °F)
TPK version: 5 ... 70 °C (41 ... 158 °F)
Storage temperature-25 ... 70 °C (-13 ... 158 °F)
Altitude≤ 2000 m above MSL
Mechanical specifications
Degree of protectionIP68
Mechanical construction
Materialfloat: PP (Polypropylene)
- PVC version: PVC cable, highly flexible (3 x 0.75 mm2)
- PUR version: PUR cable, highly flexible (3 x 0.50 mm2)
- CSM/CM version: CSM/CM cable (chlorinated polyethylene, (3 x 0.75 mm2))
- TPK version: TPK cable, (3 x 0.75 mm2)
Switching pointswitch angle, measured against the horizontal:
- upper switch point +15° ±5°
- lower switch point -15° ±5°
General information
Supplementary informationStatement of Conformity, Declaration of Conformity, Attestation of Conformity and instructions have to be observed 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 11.027200510
ECLASS 10.0.127200510
ECLASS 9.027200510
ECLASS 8.027200510
ECLASS 5.127200510
ETIM 8.0EC011178
ETIM 7.0EC011178
ETIM 6.0EC001447
ETIM 5.0EC001447
UNSPSC 12.141111950

Documents: LFL3-**-U

Instruction manualsLanguageFile TypeFile Size
ИнструкцииBULPDF125 KB
Návod k poużitíCZEPDF120 KB
Instruktions manualDANPDF119 KB
Instruction manualENGPDF43 KB
KasutusjuhendESTPDF117 KB
KäyttöohjeFINPDF116 KB
Manuel d'instructionsFRAPDF59 KB
BetriebsanleitungGERPDF47 KB
Οδηγίες χρήσηςGREPDF0 KB
HandleidingHOLPDF0 KB
Instruction manual / BetriebsanleitungHRVPDF118 KB
Használati útmutatóHUNPDF120 KB
Manuale di istruzioniITAPDF47 KB
Lietošanas pamācībaLAVPDF119 KB
Instrukciju vadovasLITPDF0 KB
Instrukcja obsługiPOLPDF122 KB
Manual de instruçõesPORPDF0 KB
Manual de utilizareRONPDF120 KB
Návod na poużitieSLKPDF120 KB
Navodila za uporaboSLVPDF118 KB
Manual de instruccionesSPAPDF58 KB
ManualSWEPDF118 KB
Technical information
Declaration of Contamination / Erklärung zur KontaminationALLPDF137 KB


CADFile TypeFile Size
3-D model / 3-D-ModellSTP482 KB
3-D model / 3-D-ModellSTP254 KB

Approvals+Certificates: LFL3-**-U

Statements of complianceCertificate No.File TypeFile Size
EU-Declaration of conformity / EU-KonformitätserklärungDOC-2349PDF68 KB

Function: LFL3-**-U

The mercury (Hg) mechanical contact (change-over contact) is encapsulated in the PP float and is activated in the event of deviations from the horizontal position.