VAT 64246-UEHC-0001 - Page 50

TROUBLE SHOOTING
Series 642
50/73
Edition 2013-08-22
603685EA
Failure
Check
Action
Pressure reading is wrong
or
pressure reading is negative
- Sensor(s) connected?
- Refer to «Electrical connection».
- 2 sensor version present at
valve controller?
- Check valve version on page 1. Verify configuration.
Refer to «Setup procedure».
- ZERO done?
- Perform ZERO when base pressure is reached. Refer to
«ZERO» for details.
- Does sensor power supply
provide enough power for
sensor(s)?
- Verify sensor supply voltage.
CLOSE VALVE does not work
- Safety mode active, check for
D on display?
- Maintenance mode active
- Provide power to motor to allow for operation.
- Refer to «Electrical connection» for details.
- Refer to “Display shows «M C»” in this table
OPEN VALVE does not work
- Safety mode active, check for
D on display?
- Maintenance mode active
- Provide power to motor to allow for operation.
- Refer to «Electrical connection» for details.
- Refer to “Display shows «M100»” in this table
ZERO does not work
- Valve in open position, check
for O on display?
- OPEN VALVE and bring chamber to base pressure
before performing ZERO.
- ZERO disabled?
- Enable ZERO.
Refer to «Valve configuration» for details.
Pressure is not ‘0’ after ZERO
- Sensor voltage shifting?
- Wait until sensor does not shift any more before
performing ZERO.
- System pumped to base
pressure?
- OPEN VALVE and bring chamber to base pressure
before performing ZERO.
- Sensor offset voltage
exceeds ±1.4V
- Replace pressure gauge.
PRESSURE CONTROL does not
work
- Safety mode active, check for
D on display?
- Provide power to motor to allow for operation.
- Refer to «Electrical connection» for details.
- PRESSURE CONTROL
selected, check for P on
display?
- Select PRESSURE CONTROL mode.
Refer to «Pressure control» for details.
- LEARN done?
- Perform LEARN.
Refer to «Setup procedure» for details.
PRESSURE CONTROL not optimal
- Setup done completely?
- Perform «Setup procedure» completely.
- LEARN done?
- Perform LEARN.
Refer to «LEARN» for details.
- ZERO performed before
LEARN?
- Perform ZERO then repeat LEARN.
Refer to «Setup procedure» for details.
- LEARN interrupted?
- Repeat LEARN.
Refer to «LEARN» for details.
- Was gas flow stable during
LEARN?
- Repeat LEARN with stable gas flow.
Refer to «LEARN» for details.
- Tuning done?
- Tune valve for application.
- Refer to «Tuning of control performance» for details.
- Is sensor range suited for
application?
- Use a sensor with suitable range (controlled pressure
should be >3% and < 98% of sensor full scale).
- Noise on sensor signal?
- Make sure a shielded sensor cable is used.
If you need any further information, please contact one of our service centers. You will find the
addresses on our website: www.vatvalve.com.