VAT 613 Series - Page 94

OPERATION Series
613
94/149 Edition 12.08.2022 984360EC
6.3.3.2 Learn
LEARN adapts the PID controller of the valve to the vacuum system and its operating conditions.
LEARN must be executed only once during system setup. The LEARN routine determines the
characteristic of the vacuum system. Based on this, the PID controller is able to run fast and accurate
pressure control cycles.
This characteristic depends on various parameters such as chamber volume, conductance and flow
regime. Therefore it must be performed with a specific gas flow according to instruction below.
The result of LEARN is a pressure versus valve position data table. This table is used to adapt the PID
parameters. The data table is stored in the device memory which is power fail save. The data table
can be up-/downloaded via ‘Control Performance Analyzer’ software or remote interface. Due to
encoding the data may not be interpreted directly.
By an OPEN VALVE, CLOSE VALVE, POSITION CONTROL or PRESSURE CONTROL command
the routine will be interrupted.
Recorded Standard Learn
Resulting Learn Data