Servomech S.p.A.
02.02-05-08-10-11-12.E - Rev. 00 Date (M/Y) 12/19
11
6.3
FCM magnetic stroke limit switches
The magnetic stroke end switches FCM allow to limit the actuator stroke length avoiding to reach the extreme
positions (mechanical stop) and preventing damage. Using more switches it is also possible to set
intermediate positions along the actuator stroke length.
The stroke end switches must be fixed on the external tube and are activated by a toroidal magnetic field
independently of their angular position.
The magnetic reed switches can work only if connected to a control circuit to activate electric relay.
Do not connect the reed switches in series between the power supply and the electric motor.
Actuators equipped with magnetic stroke end switches perform a linear travel shorter than their
stroke length code, because the reed switch FC 1 gives the stopping signal to the actuator before the
actuator has travelled the total stroke length. To know the actual stroke please refer to the product
catalogue.
When using more contact reeds for intermediate positions, it shall be considered that the same reed
switch can give the signal in 2 different positions, depending on the actuator motion which can be
retracting or extending.
Figure 6.2 – FCM magnetic stroke limit switches
FCM magnetic limit switches are supplied already fixed on extreme stroke positions Lc and La (see Fig. 6.12):
RETRACTED ACTUATOR (Lc) position: FC 1 reed switch fixed on the tube up to the actuator housing.
EXTENDED ACTUATOR (La) position: FC 2 reed switch fixed on the limit marked on the outer tube.
The position of the reed switches can be adjusted by changing the fixing clamp position on the tube:
Release the screw on the fixing clamp (do not release the fixing screw of the reed sensor)
Move the fixing clamp on the tube to the desired position (do not exceed the maximum range Lc …
La)
Fix the screw of the clamp.
DO NOT SET THE FC 2 SWITCH POSITION OVER THE LIMIT MARK ON THE TUBE.
DO NOT TRAVEL OVER THE STROKE LIMIT SWITCHES POSITIONS, AVOIDING TO REACH MECHANICAL
STOP AND PREVENTING DAMAGE TO THE INTERNAL COMPONENTS OF THE ACTUATOR.