VAT 642 Series Installation, Operating, & Maintenance Instructions page 33

Series 642
Pin
3
19
18
6
4
1) All digital inputs are digitally filtered. Filter delay is 50ms. This means that digital signals must be
applied for at least 50ms to be effective. Refer to «Function and wiring» for details about input circuit.
2) Highest priority is 1. Functions with lower priorities will not be effective as long as higher priority
functions are active.
605403ED
Function Signal Description
type
This function compensates the pressure gauge offset voltage
and sets the pressure value to zero. In case of a 2 sensor
system both sensor inputs will be adjusted.
This function is initiated by the 'off' to 'on' transition of the
optocoupler.
If 'on' remains established this will not re-initiate the function
Digital
and does also not block functions with lower priorities.
ZERO
1)
Input
The LEARN routine determines the control characteristic of
the vacuum system.
This function is initiated by the 'off' to 'on' transition of the
optocoupler. A transition from 'on' to 'off' while the routine is
running would stop it.
Digital
LEARN While running, the routine may not be interrupted by another
1)
Input
function with higher priority. If 'on' remains established after
completion this will not re-initiate the function and does also
not block functions with lower priorities.
This function locks the valve in remote operation. In case the
valve is in local operation it will turn to remote operation. Local
operation via service port is not possible when LOCK is
Digital
LOCK
1)
activated.
input
When the signal is released the valve remains in remote
operation but local operation may be activated via service port.
Ground for all digital inputs. Ground is used when digital inputs
DIGITAL Digital
are operated by switches. Connect switches to ground.
GROUND
ground
Refer also to «Function and wiring» configuration a).
Common for all digital inputs. Common is used when digital
inputs are driven by voltage sources. Connect + or – terminal
Digital
DIGITAL
of source with common (input optocouplers are capable of
comm
COMMON
bidirectional operation).
on
Refer also to «Function and wiring» configuration b).
Edition 2017-11-24
INSTALLATION
Do not perform ZERO as long as pressure gauge
voltage is shifting.
Do not perform ZERO, if the base pressure of your
vacuum system is higher than 1%o of sensor full
scale. We recommend disabling ZERO function in
this case. You can disable the function in local
operation via service port.
Without a LEARN data set the PID controller is not
able to perform pressure control.
Priority
2)
1
2)
4
N/A
33/94