Installation, Operating & Maintenance Instructions
Series 612 DN 25 (I.D. 1”), Logic
VAT Vakuumventile AG, CH-9469 Haag, Switzerland
Tel +41 81 771 61 61 Fax +41 81 771 48 30 [email protected] www.vatvalve.com
289700EB
2011-10-21
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3.1.3 Safety
mode
By means of an external switch (see connection diagrams «Electrical connection») the motor power supply can be
interrupted. In this case the valve enters the ‘safety mode’. This motor interlock prevents the valve from moving (e.g.
maintenance work). Data reading from the control unit remains possible.
When motor interlock is active during power up the valve directly enters the ‘safety mode’ and is not able to synchronize.
Display shows ‘D C’ or ‘D999’. In this case synchronization cycle will be done when motor interlock is deactivated. Then
Display shows ‘INIT’ for a moment followed by ‘SYNC’.
When ‘safety mode’ is entered from operation (i.e. pressure control mode), the unit will automatically switch to position
control mode and remain at current position. Once motor interlock is deactivated the unit remains in position control mode.
3.1.4 Service
indication
This product is able to indicate that the valve unit needs to be cleaned, or an obstruction is present.
A service request is indicated when the control unit detects that motor steps are apparently not effective. This may happen
when the valve unit is heavily contaminated. These ‚lost‘ steps are recognized and will be repeated to attempt target
position in the short term. But in the medium term the valve unit requires cleaning or inspection.
‘Service request’ (SR) would be indicated on the display or could be read via remote operation. Refer to «Display
information» for details.
3.2 Operation under increased temperature
Hot valve
Heated valve may result in minor or moderate injury.
Do not touch valve and heating device during operation. Once heating is switched off
(valve and system) await until the valve is cooled down complete before doing any
work.
This valve may be operated in the temperature range mentioned in chapter «Technical data».
3.3 Behaviour during power up
Valve position before
power up:
Reaction of valve:
Any
Valve runs a synchronization cycle (close-open-close) to detect the limit stops.
This cycle is performed with reduced torque (80%). Display shows configuration
of product until synchronization cycle is done. Refer also to chapter «Display
information».
