VA-9070 Series Electric Rotary Actuators for Two-Position and Modulating Service Technical Bulletin
13
5. Wire the potentiometer to the terminal strip using the small stick-on wiring
diagram provided.
6. Adhere the wiring diagram sticker to the inside of the cover.
Setting the Potentiometer
1. Manually operate the actuator handwheel until the unit is in the fully closed
position.
2. Rotate the black potentiometer drive gear adjustment knob to barely engage the
potentiometer gear segment at the closed position.
3. Manually operate the actuator to the fully open position.
4. Fine-tune the potentiometer adjustment at this end to equalize the difference
between the ends. The potentiometer gear segment should remain engaged
with the drive gear throughout full actuator travel.
Troubleshooting Procedures
Actuator Troubleshooting
See Table 1 for actuator troubleshooting information.
Table 1: Actuator Troubleshooting Chart (Part 1 of 2)
Problem
Possible Cause
Solution
Actuator does not
operate.
Override is engaged.
Push handwheel in all the way.
Wiring is incorrect.
Check wiring and power supply.
Actuator motor has reached its thermal
shutdown temperature
Allow time to cool.
Actuator operates in
reverse directions.
Field wiring is reversed.
Rewire field wiring.
Actuator does not
fully close valve or
open valve
Limit switches trip.
Readjust travel limit switches.
Mechanical travel stop is stopping actuator.
Adjust mechanical travel stops.
Valve torque requirement is higher than
actuator output.
Manually override out of seat; try angle
seating or larger actuator.
Optional torque switches activating
Valve torque exceeds actuator torque rating
- consult factory
Voltage power supply is low.
Check power source
Engaging override
handwheel does not
shut off motor.
Override pin is corroded or damaged.
Clean and check for smooth operation of
the override switch pin.
Override switch is damaged.
Replace switch.
