Installation, Operating & Maintenance Instructions
Series 612 DN 40 (I.D. 1.5”), RS485
VAT Vakuumventile AG, CH-9469 Haag, Switzerland
Tel +41 81 771 61 61 Fax +41 81 771 48 30 [email protected] www.vatvalve.com
289917EA
2011-07-07
53/69
Failure
Check
Action
Pressure is not ‘0’ after ZERO
- Sensor voltage shifting?
- System pumped to base pressure?
- Sensor offset voltage exceeds ±1.4V
- Wait until sensor does not shift any
more before performing ZERO.
- OPEN VALVE and bring chamber to
base pressure before performing
ZERO.
- Replace pressure
gauge.
PRESSURE CONTROL does not work
- Safety mode active, check for D on
display?
- PRESSURE CONTROL selected,
check for P on display?
- LEARN done?
- Provide power to motor to allow for
operation. Refer to «Electrical
connection» for details.
- Select PRESSURE CONTROL mode.
Refer to «Pressure control» for details.
- Perform LEARN.
Refer to «Setup procedure» for details.
PRESSURE CONTROL not optimal
- Setup done completely?
- LEARN done?
- ZERO performed before LEARN?
- LEARN interrupted?
- Was gas flow stable during LEARN?
- Tuning done?
- Is sensor range suited for application?
- Noise on sensor signal?
- Perform «Setup procedure»
completely.
- Perform LEARN. Refer to «LEARN»
for details.
- Perform ZERO then repeat LEARN.
Refer to «Setup procedure» for details.
- Repeat LEARN. Refer to «LEARN» for
details.
- Repeat LEARN with stable gas flow.
Refer to «LEARN» for details.
- Tune valve for application. Refer to
«Tuning of control performance» for
details.
- Use a sensor with suitable range
(controlled pressure should be >3%
and < 98% of sensor full scale).
- Make sure a shielded sensor cable is
used.
If you need any further information, please contact one of our service centers. You can find the addresses on our website:
http://www.vat.ch
