EB 8395 EN
27
Operating the positioner
7.9 Initialization
During initialization the positioner adapts it
-
self optimally to the friction conditions and
the signal pressure required by the control
valve.
The process is disturbed by the movement of
the actuator stem.
Do not perform the initialization while the
process is running. First isolate the plant by
closing the shut-off valves.
The type and extent of self-adaptation de-
pends on the preset parameters.
MAX is the default setting for the nominal
range (Code P4).
During the initialization process, the posi
-
tioner determines the travel range of the
valve (from the CLOSED position to the op
-
posite end position).
Alternatively, a different travel can be select-
ed in Code
P4
(see code list in section 11.2).
The travel set in Code
P4
is only limited
during initialization. However, it might be
exceeded in closed-loop control when the
control signal is higher than 20 mA.
Start initialization by activating Code P15 as
follows:
Press
or
to select Code
P15.
Press
and hold for six seconds.
6-5-4-3-
2-1-
is counted down on the display.
Initialization starts. INIT blinks on the dis-
play!
The time required for the initialization proce-
dure depends on the actuator transit time
and can take a few minutes.
Initialization successfully
completed, positioner runs
in closed-loop operation
After a successful initialization, the position
-
er changes to closed-loop operation indicat-
ed by the
%
closed-loop operation icon and
control position in % predetermined by the
reference variable on the display. Configura
-
tion is locked.
A malfunction leads to the process being in-
terrupted and the positioner moving to the
fail-safe position. The fault indication icon is
displayed (see section 9).
NOTICE
!
Note
Note
Summary of Contents for 3724
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