Setting Of Torque Limit Switches; Position Feedback Potentiometer (Option) - Bernard Controls SQ Serie Anleitung Für Die Inbetriebnahme, Lagerung Und Wartung

6 SETTING OF TORQUE LIMIT SWITCHES

IMPORTANT: the torque limit switch design of Bernard Controls actua-
tors gives a short duration contact only. On request, relays holding this
contact maintained can be fitted into the actuator.
Actuators are set and tested in accordance with the torque stated
on orders. If no torque is specified, the actuator is supplied with torque
springs set to the maximum output (refer to our catalogue technical da-
tasheets).
If necessary, this torque setting can be readjusted by rotating the nuts
which compress the torque springs. So the torque can be increased
or decreased by tightening or loosening the nuts. Please consult us.

7 POSITION FEEDBACK POTENTIOMETER (OPTION)

The potentiometer used for actuator signal feedback is driven by the travel
cam block system.
The potentiometer has no mechanical stop and has a non-resistive area
(dead zone) at both the beginning and end of track.
0% position corresponds to a closed valve. 100% to an open valve.
Circuit board mounted version
To mount the potentiometer device on the switch plate, clip it without
the position indicator on the camblock and screw it on the support
column. Screw the position indicator back.
Setting of potentiometer zero is achieved thanks to the «0% postion»
screw.
Drive the actuator to the closed position.
Resistance value is measured between terminals 16 and 17.
Hold the pinion located just under the plate with the «0% position»
marking while driving the potentiometer screw. Adjust the potentiometer
so that the resistance value exceeds 0 Ohm and regularly increases then
turn backwards to reach a value as close to 0 Ohm as possible.
Drive the actuator to the open position and write down the resistance
value corresponding to the 100% position.
Come back to the closed position and check that, for the 0% position, the
resistance shows a close to zero repeatable value.
On support column mounted version (SQ4 to SQ15)
To mount the potentiometer device, screw the support column on the mounting
plate and engage the driving pinion into the camblock wheel.
To adjust the potentiometer resistance value, loosen the nut with the wrench
and rotate potentiometer until the signal requested is archieved.
To set the 0%, drive the actuator to the closed position.
Resistance value is measured between terminals 16 and 17.
Rotate the potentiometer so that the resistance value exceeds 0 Ohm
and regularly increases then turn backwards to reach a value as close to
0 Ohm as possible.
Retighten nut after setting.
English
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