7 Partial stroke testing over DP-V0
The partial stroke test (PST) can be started in the following ways:
Operating mode Test mode PST
Start over binary
input
Start with auto test
time
Start over
reference variable
AUTO
PST MAN • – •
1)
PST AUTO • • •
1)
MAN
PST MAN • – –
PST AUTO • • –
1)
The partial stroke test is started by defining SP with status value (9C hexadecimal). This function
must be enabled by the FEATURE_SELECT parameter.
The partial stroke test cannot be started when the fail-safe action (FSAFE_TYPE) is active.
The partial stroke test is analyzed by the DI Function Block (Discrete Input) of the positioner.
In this case, one of the following alarms is assigned to the discrete data:
0: Test not performed successfully
1: Test OK
2: PST has not been performed
3: Test analysis not successful
For further analysis, the condensed state can be analyzed with the second DI Function Block
(see section 5.2).
Note: Partial stroke testing is described in detail in the Operating Instructions EB 8389 EN on
EXPERTplus valve diagnostics.
KH 8384-4 EN 37
Partial stroke testing over DP-V0