Servomech S.p.A.
16.30-40-50.E - Rev. 01 DD (M/Y) 05/19
17
6.5
Set up of POR 5k potentiometer
SET UP THE POTENTIOMETER BEFORE TO ADJUST THE CAMS LIMIT SWITCHES.
In case of actuator with anti-turn device option (AR), the POR 5k potentiometer is supplied already
SET UP by the factory.
SET-UP INSTRUCTIONS
1. Open the switches box cover
Before removing the switches cover, make sure that the cables are free by unscrewing the threaded
glands, to avoid to break the welded contacts between the wires and switches or the potentiometer
pins.
Then unscrew two fixing screws and remove the cover.
2. Recognize the extreme positions of the transducer
Look at the little dot under the potentiometer trademark.
When the transducer is rotated counterclockwise, and the dot is near the terminal with the yellow
and white wires, the transducer is on the MINIMUM RESISTANCE position.
When the transducer is rotated clockwise, and the dot is near the terminal with the brown wire, the
transducer is on the MAXIMUM RESISTANCE position.
IF THE MARKER IS OVER THE EXTREME LIMIT POSITIONS ABOVE MENTIONED, THE POTENTIOMETER
EXITS THE ELECTRICAL WORKING ANGLE CAUSING THE SIGNAL INTERRUPTION!
3. Rotary potentiometer setup
•
Depending on its current position, screw in or unscrew, by hand, the push rod in order to be at about
half of stroke.
•
Make the actuator run by rotating the auxiliary input shaft or by powering the electric motor, until the
ohmmetric value between the wires green and yellow is (30 ... 35) Ω (minimum resistance position).
WARNING! DURING THIS OPERATION, THE LC (RETRACTED ATUATOR) AND LA (EXTENDED
ACTUATOR) POSITIONS, INDICATED ON THE CHECK SHEET SUPPLIED IN ATTACHMENT TO THE
ACTUATOR OR IN THE CATALOGUE, MUST NOT BE EXCEEDED! IF NECESSARY, SCREW IN OR
UNSCREW THE PUSH ROD AGAIN.
•
Screw the push rod in, in order to reach the Lc (RETRACTED ACTUATOR) position. With this operation,
the rotary potentiometer setting is finished and, from this moment, the push rod rotation must be
avoided! Any push rod rotation will invalid the already done rotary potentiometer setting.
•
Connect the rotary potentiometer to the control circuit. Power the motor on, in order to extend the
actuator first and then to retract it.
MARKER
Counterclockwise rotation – Push rod IN
Clockwise rotation – Push rod OUT