Samson Electri Actuator Type 3374 EB 8331-1 EN - Manual (Page 14)

4.3 Setting the digital positioner
In the actuator version with digital
positioner, the travel is calibrated automati-
cally, allowing the travel (controlled variable
x) and the input signal (reference variable
w) of the positioner to be matched in the
best possible way. Additionally, the digital
positioner provides valve position feedback
for remote transmission.
Setting and start-up can be carried out using
four different operating modes. Operating
modes 1 and 2 work with set data stored in
the positioner's memory. The user only
needs to select the operating mode via the
selector switch (2) and press the button (4)
to start travel calibration.
Note: Setup with operating modes 3 and 0
= can only be performed using a
SAMSON memory pen as the storage me-
dium, or in connection with SAMSON's
TROVIS-VIEW Configuration and Operator
Interface software and a PC or bus system.
Setup with operating modes 3 and 0 = is
described in Mounting and Operating In-
structions EB 8331-2 EN.
Settings for operating modes 1 and 2
Increasing characteristic: actuator stem re-
tracts or extends as the input signal in-
creases.
After the actuator has been mounted on the
valve as described in section 2.2 and the
electrical connections have been established
as described in section 3, proceed as fol-
lows:
1. Set selector switch (2) with the arrow
pointing to operating mode 0 =
(closed-loop operation switched off).
2. Check mounting position of the potenti-
ometer gear (12).
The gear must be put onto the potentiometer
shaft to correspond with the rated travel of
the valve. The inscription Nennhub 15 or B
(for 6 to 19 mm travel) or Nennhub 30 or A
(for 6 to 35 mm travel) must be legible from
above on the associated gear side. If this is
not the case, pull the gear off the shaft and
put it back on again with the reverse side
facing upwards, allowing the intermediate
gear to engage properly.
NOTICE
Actuators with fail-safe action "Actuator
stem retracts" or "extends" are only de-
signed for a rated travel of 15 mm. Do not
reposition the gear!
Make sure that the shaft of the potentiometer
(12.1) is adjusted correctly.
3. Switch on power supply and set the in-
put signal to a current > 4 mA.
4. Set selector switch (2) with the arrow
pointing to operating mode 1 for 4 to
20 mA or 2 to 10 V input and alarm
signal, or set it to operating mode 2 for
0 to 20 mA or 0 to 10 V input and
alarm signal.
5. Press button (4) to start travel calibra-
tion.
14
EB 8331-1 EN
Operation and setting