Servomech S.p.A.
02.02-05-08-10-11-12.E - Rev. 00 Date (M/Y) 12/19
10
6.2
FCE electric stroke limit switches
The electric stroke limit device is only available for actuators ATL 10-12 and BSA 10-11-12.
The ELECTRIC STROKE LENGTH LIMIT DEVICE allows to limit the actuator stroke length avoiding to reach the
extreme positions (mechanical stop) and preventing damage.
The FCE device consists of 2 normally closed electric switches installed inside a sealed box made in
engineering plastic or aluminium alloy. A brass collar allows, with its special shape, activation of the electric
switches. It is balanced by 2 opposite preloaded helical springs, which reset the position when the actuator
starts moving again in the opposite direction. 2 wiper seals between the axial travelling collar and the
housing. The activation of the collar, and consequently of the limit switches, in one or in the opposite
direction is done by a stainless steel rod driven by the push rod. The stainless steel rod slides inside the collar
activating it when the adjustable ring pushes on the collar, which activates the switch.
Figure 6.1 – FCE electric stroke limit switches
Ring 1 activates FC 1 switch and fixes the required RETRACTED ACTUATOR stop position.
Ring 2 activates FC 2 switch and fixes the required EXTENDED ACTUATOR stop position.
To setup the stop positions: simply release the grub screw on the ring, move it on the required stop
position and fix the screw again.
The maximum ring positions on the rod consist on the extreme stroke lengths positions “Lc” and “La”
(see Fig. 6.12).
The ELECTRIC STROKE LENGTH LIMIT DEVICE must be connected to the electric control circuit as shown in
the following WIRING DIAGRAM.
CONTROL CIRCUIT
ELECTRIC SWITCH – TECHNICAL FEATURES
Contact
NC (normally closed)
Voltage
250 V AC
30 V DC
125 V DC
Current (resistive load)
5 A
5 A
1.4 A
Current (inductive load)
3 A
0.1 A
—
Outlet
Multicore PVC cable 4 × 0.75 mm
2
length 1.5 m
Wiring
WHITE – NC contact of FC1
BROWN – COM contact of FC1
YELLOW – NC contact of FC1
GREEN – COM contact of FC2
DO NOT TRAVEL OVER THE STROKE LIMIT SWITCHES POSITIONS, IN ORDER TO AVOID DAMAGES TO
THE LIMIT SWITCHES DEVICE.
In case of high speed application (≥ 30 mm/s linear speed) and/or with high inertia load, be sure to
slow down the motor before to reach the limit switches position. Use the motor brake (if present) to
ensure the stop position.
THE FCE ELECTRIC STROKE LIMIT DEVICE CANNOT BE USED AS ANTI-TURN DEVICE OF THE PUSH ROD.