Rotary Limit Switch

The rotary limit switch is a device which allows you to control the movement of industrial and building machines.

The shaft is connected to the motor, so that, after a certain number of turns, the cams make the switches work, and then they can carry out their pre-set manoeuvre. The range of FCN rotary limit switches has been planned with a particular internal symmetry that allows you to have a series of 5 microswitches (on-off exits) as well as some other linear exits, and a potentiometer in the same box.

The innovative and thorough regulation of the cams allows you to set the microswitches working point linearly and micrometrically. Reduction ratios range turns out to be remarkably large, since microswitches can be fitted with guaranteed opening (EN 60947-5-1) as well as deviation or progressive double opening contacts.

The choice of different cam profiles allows you to modify the limit switches function diagram.

  • Technical Features
  • Standards
  • Models
  • Accessories
  • Spare Parts
  • Download

Main Features

  • Insulation voltage 250V~
  • Maximum operating voltage 250V~
  • Black lower casing reinforced nylon
  • Yellow cover high mechanical and thermal resistant thermoplastic
  • Operating temperature - 20 °C + 60 °C
  • Drive worm screw
  • Cable entries PG 11
  • Protection against contact voltages double insulation
  • Weight 460 g (approx.)

Regulation Criteria

Each cam is equipped with its own micrometer regulating screw. Each screw operates exclusively on the cam it is combined with, without interfering mechanically against its adjacent cams.

Regulation can simply be carried out by rotating the regulating screw through a small blade screwdriver. Thanks to a particular friction system, rapidity and regulation precision are assured, which makes the structure stable, steady and reliable.



1 NC safety slow type P
1 NA NO safety 1 NC rapid typeD 
2 NC safety progressive type M 
1 NA 1 NC safety slow type MD
Insulation Voltage Ui
250 V~
Test Voltage
200 V~
Operating current
10³ A
Breaking power
secondo EN 60947-5-1
Mechanical Lifetime
2x10⁶ man
with screws


24 48 110 230
10 10 6 3
24 48 110 230
3 1,5 1 0,5

EC Regulations

  • 98/37/CE
  • 2006/95/CE

  • CEI EN 60947-1
  • CEI EN 60947-5-1
  • CEI EN 60204-1
  • CEI EN 60529
  • CEI EN 60439-1

  • IP 55 CEI EN 60529

Standard Executions

Reduction ratios
  • 1:7,5  rotations
  • 1:15   rotations
  • 1:25   rotations
  • 1:35   rotations
  • 1:50   rotations
  • 1:60   rotations
  • 1:100 rotations
  • 1:140 rotations
  • 1:200 rotations
  • 1:275 rotations
  • 1:400 rotations
  • 1:550 rotations

Standard executions are provided with 2 or even 4 contacts. Limit switches with 3 and 5 contacts can also be realized upon request and according to the necessary quantity.

Order Codes

GroupSeriesReduction rationsContact type (P-D-M-MD)
Contact numbers (2-3-4-5) 
Where a potentiometer is required, it is necessary to add after the number of contacts:
  • K 5 for 5 Kohm potentiometer - K 10 for10 Kohm potentiometer
If not specified, limit switches are supplied with white type A cams. To specify a cam different from white type A, it is necessary to add:
  • B for 45° level - C for 90° level - D for 180° level

Custom Execution

FCN limit switches can be customized according to the order quantity. Specific customizations:
  • shafts cut to measure
  • cable entry in frontal or lateral position
  • different contacts
  • regulation cams with different profiles
  • measuring accessories, such as potentiometers or encoders
  • customized nameplates


The range of the accessories integrates and completes the limit switches series and facilitates their use according to particular requirements. A series of cog wheels, a male connection and a flexible shaft are the interfaces which have specifically been designed in order to transmit the motion easily from the motor shaft to the limit switch shaft. The fitting of a potentiometer, an encoder or another position sensor close to the micro switch group involves a linear exit in the same box.

Cog Wheels

A series of cog wheels of different diameters allows you an easy joining through pinions and belts.

Available wheels:
  • Module 5 with 12 teeth
  • Module 6 with 11 teeth
  • Module 8 with 12 teeth
  • Module 10 with 12 teeth
  • Module 14 with 10 teeth

Male Connection

The male connection helps the joining to motors or reducing gears.

Flexible Shaft

The flexible shaft allows you to couple the shafts that are not perfectly aligned.

Attachment Flange

The flange interface allows the limit switch to be fixed without the special fixing plate.


The insertion of a potentiometer near the microswitch group involves a linear exit in the same box.

  • Ensure that the locking screw is loosened.
  • Set the desired resistance value by means of the instruments by rotating the regulating ring clockwise to reduce it, or anti-clockwise to increase it.
  • Tighten the lock screw

IMPORTANT: The potentiometer follows the cams rotation direction.


  Potentiometer Electrical Features Potentiometer Mechanical Features  
Total Resistance Rt 5-10 K  Operating Temperaure -40°C +125°C 
Rt tolerance at 20°C +-20%  Dimensions Diam. 22,2 mm 
Maximum power dissipated at 70°C  0,3 W  Regulation

See above

Actual electric angle AEA 340° +-5% Mechanical Angle 360° continuous 
Useful electric angle AEA -3° Shaft Stainless-sttel, with cut
Iindipendent linearity +-2% Shaft guide CBush bearing
Output voltage stability 0,1% Cursor Precision contact
Cursor current (in continuous duty) 1 mA max Mounting Sleeve
Contact load resistance > 1000 x Rt Terminals Turret
Insulation resistance 1000 M - 550 Vcc Fixing accessories Nut and washer
Dielettrica rigidity >500V eff - 50 hz Useful life 5x10⁶ cycles

Spare Parts and Accessories

Position Code  Description  Position  Code  Description 
1    B50454 Cover 2-3 micro 4      BMOD5FC Cog wheel mod 5 Z12
B50442 Cover 4 micro  BMOD6FC  Cog wheel mod 6 Z11
B50447 Cover 5 micro  BMOD8FC  Cog wheel mod 8 Z12
2 BLEVFCNA White cam A  BMOD10FC  Cog wheel mod 10 Z12 
BLEVFCNB  Grey cam B  BMOD14FC  Cog wheel mod 14 Z10 
BLEVFCNC  Red cam C  BINNFC  Male connection 
BLEVFCND  White cam D  BAFLESFC  Flexible Shaft
3     BFCNAPINT Contact 1 NC AP slow (P)  BFLANFCN  Attachment flange 
BFCNDINT  Contact 1 NA 1 NC quick (D)  Potentiometer 
BAPO2PRFC  Contact 2 NC progressive slow (M)  - Encoder (on request) 
BAP11FC  Contact 1 NA 1 NC slow (MD)       
Request information about this product