Preliminary Tests; Setting Of Mechanical Stops And Travel Limit Switches - Bernard Controls SQX TOTAL N31272 Manuel De Mise En Service

6 PRELIMINARY TESTS

a) Open the front cover. Due to its high level of tightness,
in order to ease the opening, we do recommend to screw
two M8 screws (minimum length 40mm) into the two holes
(cf. fig.3).
b) Move the valve manually to an half-open position,
c) Operate an electrical opening and check that the motor ro-
tates 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,
d) 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 wor-
king 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.

7 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 located 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 auxiliary limit switches.
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.
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 tole-
rance 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).
M8 screws
(fig. 3)
9