Setting Of Mechanical Stops And Travel Limit Switches; Setting Of Torque Limit Switches - Bernard SD Serie Instructions De Mise En Service

system (see wiring examples) in order to prevent potential damage to the
actuator or valve.
The following points must be checked :
a) Make sure that power supply voltage is in accordance with the data
engraved on the actuator nameplate,
b) Check that all cable glands are correctly tightened,
c) Move the valve manually to an half-open position,
d) Operate an electrical opening and check that the motor rotates in the right
direction. Press manually on the "OPEN" travel limit switch ; the motor
should stop.
In the same way, check that the closing electrical command as well as the
"CLOSED" travel limit switch are working correctly,
e) All models except OA : operate an electrical opening. Press manually on
the "OPEN" torque limit switch ; the motor should stop.
In the same way, operate an electrical closing check that the "CLOSED"
torque limit switch is working correctly,
If any misfunction was detected at this stage, please check the overall wiring.
For safer working conditions, we recommend that the power supply now be
switched off especially if the actuator output max. torque exceeds 300 N.m.

5. SETTING OF MECHANICAL STOPS AND TRAVEL LIMIT SWITCHES

Mechanical stops description and function (1/4 Turn only) :
These items avoid any over-travelling during handwheel operations. The
stops can be positioned either on the actuator itself or on the 1/4 Turn worm
gearbox if any.
Actuators and gears are supplied and tested for a 90° operation. Fine
adjustment of the stop screws position is possible within a limit of ± 2°
maximum.
Travel limit switches description and function :
The cams operating the limit switches are on a cylindrical block which does
not require any disassembly. Each cam can be set independently of the
others. The white and black cams are for open and close travel limits. The
other ones are for optional additional limit switches (2 or 4).
How to operate the cams :
a) Put a screwdriver in the slot of the button encircled by the same color as
the cam to be set,
b) Press lightly to disengage the cam of locked position,
c) By turning the screwdriver rotate the cam to the position in which it can
trip the limit switch,
d) Remove screwdriver and ensure that the button has come back to its
original position, thus locking the cam in chosen place.
Procedure of mechanical stops and travel limit switches setting :
a) Loosen stop screws by 2 turns (1/4 Turn only).
b) Manually drive the valve to the closed position. For the 1/4 Turn devices,
if mechanical stops are reached before the valve closing is completed, it
means that the 2° maximum adjustment tolerance has been exceeded ;
do not try to go beyond this limit.
c) Set the cam of the "CLOSED" travel limit switch.
d) Turn stop screws clockwise to the mechanical contact, reloosen 1.5 turn,
and secure by lock nut (1/4 Turn only).
Proceed in the same way in open position.
Perform complete electrical valve opening and closing operations. It is
mandatory that the motor stops on the travel limit switch and not on the
mechanical stop (check available extra travel to the stop with handwheel).
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