GEA T.VIS M-20 FDD, Инструкция по эксплуатации

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3.2 Functional description
3.2.1 Operation Principle
The control top T.VIS M-20 FDD works with a microprocessor that contains the
software for operation, visualization and intelligent position detection.
The valve stroke is detected by a contactless position measuring system
integrated in the control top and the information is supplied to the
microprocessor.
Pneumatic and electronic components are located inside the control top. The
pneumatic components in this case are solenoid valves, the number of which
varies between 0 and 1, depending on the intended purpose. Control air is
supplied to the relevant control air chambers via air connections at the outside of
the control top. On the VARIVENT valve FDD, the main control air is supplied to
the actuator via a separate air connection on the control top through a hose.
The main task of the 24V DC sensor module with its integrated path measuring
system is to determine the valve position on the basis of the position of the valve
stem and to generate the corresponding feedback signals for this position in
order to send them to a higher-level control system.
Due to the illuminated dome integrated in the hood of the control top the light
emitting diodes arranged on the sensor module can be seen even if the hood is
closed. The light-emitting diode allows visualisation of the remaining functions of
the valve, see Section 6.5, Page 31.
3.2.2 Control top without solenoid valves
The control top T.VIS M-20 FDD without solenoid valves works as a position
indicator. During and after SETUP it indicates the status of the process valve
locally by a coloured LED under the illuminated dome so that it is visible over a
long distance.
The position feedback signals are supplied to the user by means of the following
communication method:
•
24V DC PNP switching output
3.2.3 Control Top with Solenoid Valves
The control top with solenoid valves acts as a control top. The signalling takes
place in the same way as with the control top without solenoid valves. with the
difference being that the solenoid valve integrated in the base is operated in
accordance with the control signals.
The control signals are given by the user's process control system or by
operating the solenoid valves manually. To do this, use a screwdriver to turn the
screw (S) from 0 to 1, see figure.
Description
Functional description
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