3.2
Functional description
3.2.1
Operation Principle
Pneumatic and electronic modules are located inside the control top T.VIS E-20.
The pneumatic modules in this case are solenoid valves, the number of which
varies between 0 and 3, 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 VARIVENT valves and ECOVENT standard valves, the main
control air is guided through the switch bar. On process valves which do not allow
the air to be guided internally, the main control air is supplied to the actuator via a
hose connected to a separate air connection. The exhaust air of the main
actuator is discharged via an air connection with sound absorber or optionally via
an adjustable exhaust air throttle. Exhaust air from the optional lifting actuators is
discharged from the control top via a venting diaphragm and via a non-return
valve.
The main task of the sensor module with its sensors 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 cap of the control top the light
emitting diodes arranged on the sensor module can be seen even if the cap is
closed. The 2 differently coloured LEDs allow visualization of the main functions
of the valve.
Visualization:
•
Valve in non-actuated position – green
•
Valve in actuated position – yellow
•
Valve deviating from its adjusted actuated positions – no indication.
•
Valve idle – no indication
3.2.2
Control top without solenoid valves
The control top T.VIS E-20 without solenoid valves works as a position indicator.
Once the two sensors have been adjusted, the control top indicates the status of
the process valve locally by coloured LEDs under the illuminated dome.
The position feedback signals are supplied to the user in one of the following
ways, depending on the communication method selected:
•
12V DC or 24V DC switching output
To adjust the second sensor, the process valve must be moved once to its end
positions by an external solenoid valve.
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. Depending on the design of the process
valve, up to 3 solenoid valves can be installed in the control top.
Description
Functional description
430BAL013985EN_6
25.04.2023
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