Ytc YT-1000L, Product Manual

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YT-1000/1050 series
5.7 Adjustment - Orifice
If the actuator size is too small relative to the flow rate, positioner can have hunting /
oscillation. In order to avoid hunting, the orifice must be inserted.
1. Remove the pilot relay assembly from the positioner.
2. Remove the o-rings from OUT1 and OUT2 port per above diagram, and insert proper
orifice. Before re-assemble the o-rings, please make sure there is no dust or particles
remain on the ports.
5.8 Adjustment - Potentiometer
External damage or physical shock can dislocate potentiometers factory setting.
Potentiometer must be re-calibrated when dislocation of the potentiometer or after cam
adjustment.
PLEASE REFER BELOW INSTRUCTION AND DIAGRAM.
1. Please set actuator position to 50% of the valve stroke. PLEASE MAKE SURE THAT
THE ACTUATOR DOES NOT MOVE DURING THE RE-CALIBRATION.
2. In the junction box, please pull out the potentiometer connector from potentiometer PCB.
DO NOT PULL WITH TOO MUCH FORCE AS WIRES CAN BE DAMAGED.
3. On the potentiometer connector, there are three holes. Out of three holes, please
measure resistance level by plugging two holes < one of right or left and one of
center>.
The potentiometer resistance level should be between 0~10 K
Ώ and please
adjust measurement equipment to measure between above mentioned range.
4. Using “+” screw driver, loosen potentiometer stopper bolt. DO NOT LOOSEN
COMPLETELY.
5. Pull potentiometer behind and potentiometer will be separated from potentiometer gear.
This will make user to turn potentiometer gear.
6. Since current actuator position is 50% of the valve stroke, the resistance level should be
measure around 5K
Ώ (4.8 ~ 4.2 K Ώ) by turning potentiometer gear.
7.
After the setting, assemble back the stopper and the bolt.