Partial Valve Stroke Test (Pvst) - AUMA AC 01.2 Manual

Actuator controls
AC 01.2/ACExC 01.2
Information
9.9.

Partial Valve Stroke Test (PVST)

Characteristics
Requirements
Example
Figure 54: EMERGENCY stop button on the electrical connection
The EMERGENCY stop button is intended for operation in an emergency. For
maintenance work, the mains supply of the AC has to be switched off and pro-
tected against accidental switching on.
The EMERGENCY stop button is not available for the ACExC, but only for the
weatherproof versions of the AC.
Operation commands
After having unlocked the EMERGENCY stop button, a possibly active operation
command will NOT immediately be re-activated, but only respective acknowledgement
by the operator. This resets the EMERGENCY stop status.
The acknowledgement is made:
via the RESET push button in selector switch position Local control (LOCAL).
via a digital input from Remote. Assignment: RESET
Option
The Partial Valve Stroke Test (PVST) is used to check the function of both actuator
and actuator controls. During this test, the function of the valve is tested by means
of partial opening or closing within a defined period of time without interrupting the
process. After successful testing, actuator controls operate the actuator to its initial
position.
If the test was not successful, actuator controls will generate the following signals:
PVST fault PVST abort For monitoring the PVST, these signals must be evaluated
by a PLC.
Position transmitter in the actuator
Function <Positioner> activated.
If the actuator is in safe state (caused by the failure behaviour), the test will not
be performed.
The test can only be performed during OPEN - CLOSE control. For setpoint
control (modulating duty), a test cannot be performed.
For the change-over, a digital input for the signal Execute PVST has to be available
and configured.
Configuration of digital input
Required user level: Specialist (4).
Device configuration M0053
I/O interface M0139
Digital inputs M0116
Use input DIN 5 for Execute PVST signal :
Parameter: Signal DIN 4 M0118
Failure functions
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