–
Solenoid valve with parallel forced venting
–
Binary input
–
External position sensor (Fig. 4)
–
Stainless steel housing
–
Leakage sensor to monitor the seat leakage
Principle of operation
The electropneumatic positioner is attached to pneumatic con
-
trol valves. It is used to assign the valve stem position (controlled
variable x) to the input signal (reference variable w). The input
signal received from a control system is compared to the travel
or opening angle of the control valve and an output signal pres
-
sure (output variable y) is produced.
The positioner consists of an electric travel sensor system (2), an
analog i/p converter with a downstream air capacity booster
and the electronics unit with microcontroller (5).
When a deviation occurs, the actuator is pressurized or vented.
If required, the changes in the signal pressure can be slowed
down by a volume restriction. The signal pressure to the actua
-
tor can be limited by software between 1.4 and 7.0 bar.
A constant air stream to the atmosphere is created by the flow
regulator (9) with a fixed set point. The air stream is used to
purge the inside of the case as well as to optimize the air capac
-
ity booster. The i/p module (6) is supplied with a constant up
-
stream pressure by the pressure regulator (8) to make it inde
-
pendent of the supply air pressure.
Operation
The positioner is operated using a user-friendly rotary
pushbutton. The parameters are selected by turning the rotary
pushbutton, pushing it activates the required settings. In the
menu, all parameters are listed in one level, meaning there is no
need to search through submenus. All parameters can be
checked and changed on site.
All values are displayed on the LCD. The reading direction of the
LCD can be rotated by 180° at the push of a button.
The closing direction of the control valve is indicated to the
positioner by the slide switch "Air to open/Air to close". It assigns
the CLOSED position of the control valve to the 0 % reading.
The INIT key activates initialization, which is started according
to (pre)set parameters (autotune). After initialization has been
completed, the positioner immediately starts closed-loop opera
-
tion.
To configure the positioner with SAMSON’s TROVIS-VIEW con
-
figuration software, the positioner is equipped with an additional
digital interface to be connected to the RS-232 interface of a PC.
Additionally, all parameters of the Type 3730-6 Positioner can
be accessed using HART
®
communication.
2
T 8384-6 EN
%
mm
PD
FSK
w
x
Q
S
GG
Serial
Interface
16
13
22
15
A2
A3
BE
A1
11
2
4
21
20
19
5
3
12 25
6
7
23
8
10
1
14
14
w
x
y
24 V DC
9
17 18
>3.8 mA
>12 V
&
24
Fig. 5 · Functional diagram of Type 3730-6 Positioner
Legend
1 Control valve
2 Travel sensor
3 PD controller
4 A/D converter
5 Microcontroller
6 i/p module
7 Air capacity booster
8 Pressure regulator
9 Flow regulator
10 Volume restriction
11 Inductive limit switch(optional)
12 Solenoid valve (optional)
13 Analog position transmitter or
binary input (optional)
14 Software limit switches A1/A2
15 Fault alarm output A3
16 LCD
17 Control of solenoid valve (optional)
19 D/A converter
20 Communication interface
21 HART
®
modulation
22 Binary input BE (optional)
23 Pressure sensor for supply air p
s
24 Pressure sensor for signal air p
out
25 Forced venting (optional)
(12 Seiten)
(11 Seiten)
Manymanuals.com
Manymanuals.de
Manymanuals.fr
Manymanuals.it
Manymanuals.pl
Manymanuals.cz
Manymanuals.es
Manymanuals-pt.com
Kommentare zu diesen Handbüchern