Samson 3730-4, Монтаж и эксплуатация

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Turn until the valve reaches its OPEN po-
sition, press .
4
Press INIT key to start initialization!
The initialization procedure may take
several minutes, depending on the
actuator size, as the valve moves
through its entire travel/angle of ro-
tation range.
Positioners with EXPERT + diagnostic func-
tions automatically start plotting the refer-
ence graphs after the initialization process
has been completed. See page 63.
SUb
(substitute configuration, without initializa-
tion)
A complete initialization procedure takes
several minutes and requires the valve to
move through its entire travel range several
times. In the event a positioner must be re-
placed while the plant is running, this mode
allows the replacement to be performed with
the minimum amount of disruption to the
plant.
This initialization mode is an emergency
mode. The positioner parameters are esti-
mated and not determined by an initializa-
tion procedure, so that a high stationary ac-
curacy cannot be expected.
You should always select a different initial-
ization mode if the plant allows it.
The initialization mode SUb is used to re-
place a positioner while the process is in op-
eration. For this purpose, the control valve is
usually fixed mechanically in a certain posi-
tion, or pneumatically by means of a pres-
sure signal which is routed to the actuator
externally. The blocking position ensures
that the plant continues to operate with this
valve position.
The spare positioner should not be initial-
ized. If necessary, reset the spare positioner
using Code
36 .
After the old positioner has been replaced
with a new one, the following parameters
must be entered: pin position (Code
4 ),
nominal range (Code 5 ), direction of action
(Code 7 ) and closing direction (Code 34 ).
The default travel limit of 100 % (Code
11
)
must be disabled with
OFF
.
In addition, the blocking position (Code
35
)
must be adjusted with the button so that
it matches the position of the previously
blocked valve.
The parameters K
P
(Code 17 ), T
V
(Code 18 )
and the pressure limit (Code 16 ) should re-
main set to their default values. If the config-
uration data of the new positioner are
known, it is recommended to accept its K
P
and T
V
values.
After defining the valve closed position with
the AIR TO OPEN/CLOSE switch, setting the
volume restriction and pressing the INIT key,
the positioner calculates its configuration
data on the basis of the blocking position
and the closing direction as well as the other
entered data.
The positioner switches to manual operation,
subsequently the blocking position should be
canceled as described on page 69.
EB 8384-4 EN
67
Start-up and settings