Emerson Vilter Vission 20/20 Operation And Service Manual page 140

Section 14 • Slide Calibration
Problem
The actuator goes into calibration mode
spontaneously.
The actuator goes into calibration mode
every time power is restored after a power
loss
The actuator does not transmit the correct
position after a power loss.
There is a rapid clicking noise when the mo-
tor is operating.
The motor operates in one direction only
14 – 8
Table 14-2. Slide Valve Troubleshooting Guide (2 of 3)
The white calibrate wire in the
grey Turck cable is grounding
intermittently.
A very strong source of elec-
tromagnetic interference (EMI),
such as a contactor, is in the
vicinity of the actuator or grey
cable.
There is an intermittent failure of
the position sensor
The motor brake is not working
properly.
The position sensor's EEPROM
memory has failed
The motor was manually moved
while the position sensor was
not powered.
The motor brake is not working
properly.
The position sensor's EEPROM
memory has failed
The photo-chopper is mis-
aligned with the slotted
optocouplers.
The photo-chopper is positioned
too low on the motor shaft.
A motor bearing has failed
There is a loose connection in
the screw terminal blocks.
There is a loose or dirty connec-
tion in the yellow Turck cable.
The position sensor has failed.
There is a broken motor lead or
winding
Reason
Vission 20/20 • Operation and Service Manual • Emerson • 35391SC 2.7
Solution
Tape the end of the white wire in
the panel and make sure that it
cannot touch metal.
Increase the distance between
the EMI source and the actuator.
Install additional metal shielding
material between the EMI source
and the actuator or cable.
Replace the actuator.
Get the motor brake to where it
operates freely and recalibrate.
Replace the actuator.
Recalibrate.
Get the motor brake to where it
operates freely and recalibrate.
Replace the actuator.
Try to realign or replace the
actuator.
Adjust the photo-chopper so that
the fence extends further into the
optocoupler slots.
Replace the actuator.
Tighten
Clean an tighten
Replace the actuator.
Replace the actuator.