Start-Up And Settings; Defining The Fail-Safe Position - Samson 3730-2 Mounting And Operating Instructions

7 Start-up and settings

NOTICE
!
Risk of malfunction due to incorrect sequence
of mounting, installation, and start-up.
Keep the following sequence.
1. Remove the protective film from the pneu-
matic connections.
2. Mount the positioner on the control valve.
3. Connect the supply air.
4. Connect the electrical power.
5. Perform the start-up settings.
Reading after connecting the electrical pow-
er supply:
tEStinG runs across the display and the
fault alarm icon appears and blinks on the
display when the positioner has not been
initialized. The reading indicates the lever
position in degrees in relation to the mid-ax-
is.
Code 0 is displayed when a positioner has
been initialized. The positioner is in the last
active operating mode.
WARNING
!
Risk of injury due to the actuator stem ex-
tending or retracting.
Do not touch or block the actuator stem.
EB 8384-2 EN
Reading when the positioner
has not yet been initialized
Note
The positioner performs a test in the start-up
phase while following its automation task at
the same time.
During the start-up phase, operation on site
is unrestricted, yet write access is limited.
Perform the start-up settings in the same se-
quence as described (section 7.1 to sec-
tion 7.6).
7.1 Defining the fail-safe posi-
tion
Define the fail-safe position of the valve
(0 %) taking the valve type and the actua-
tor's direction of action into account. Position
the AIR TO OPEN/AIR TO CLOSE slide
switch accordingly:
− AIR TO OPEN setting
Signal pressure opens the valve, e.g. for
a fail-close valve
The AIR TO OPEN setting always applies to
double-acting actuators.
− AIR TO CLOSE setting
Signal pressure closes the valve, e.g. for
a fail-open valve
For checking purposes: after successfully
completing initialization, the positioner dis-
play must read 0 % when the valve is closed
and 100 % when the valve is open. If this is
not the case, change the slide switch position
and re-initialize the positioner.
Start-up and settings
63