Samson TROVIS 3730-3, Монтаж и эксплуатация

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EB 8384-3 EN 19
Design and principle of operation
as a 4 to 20 mA signal processed by the mi -
crocontroller.
Since this signal is issued independent of the
positioner’s input signal (minimum current
3.8 mA), the momentary travel/angle of ro -
tation is controlled in real-time. Additionally,
the position transmitter allows positioner
faults to be indicated over a signal current of
<2.4 mA or >21.6 mA.
Inductive limit switch
In this version, the rotary shaft of the posi-
tioner carries an adjustable tag which actu-
ates the built-in proximity switch. The option-
al inductive switch (11) is connected to A1,
while the remaining software limit switch is
connected to A2.
External position sensor
In this version, only the sensor is mounted to
the control valve. The positioner is located
separately from the valve. The connection of
x and y signals to the valve is established by
cable and piping for air (only without induc-
tive limit switch).
Analog input x
The analog input x option allows commer-
cially available external linear or angle posi-
tion sensors that use a 4 to 20 mA signal to
be connected to the positioner. The analog
input x is protected against reverse polarity
and overload up to 24 V AC/DC. The posi -
tioner switches to open-loop operation (no
closed-loop operation) as soon as the input
signal falls below 2.5 mA.
Leakage sensor
By upgrading the positioner with a leakage
sensor, it is possible to detect seat leakage
when the valve is in the closed position.
Binary input
Positioners can be optionally fitted with a bi -
nary input. The following actions can be trig-
gered by changing the edge state:
−
Transmit switching state [default]
The switching state of the binary input is
logged.
− Set on-site operation write protection
While the binary input is active, no set -
tings can be changed at the positioner.
Enabling configuration over Code 3 is
not active.
−
Switch between AUTO/MAN
The positioner changes from the auto-
matic mode (AUTO) to the manual
mode (MAN) or vice versa.
This function is not performed if the posi-
tioner is in the fail-safe position mode
(SAFE).
−
Various diagnostic functions
u
EB 8389
(EXPERTplus valve diagnostics)
− The optional binary input can only be con -
figured using the TROVIS-VIEW software
and using the DD parameters (
u
EB 8389
on EXPERTplus valve diagnostics).
− The default switching state is with an open
switch.
Note