| Network Systems for valve automation
As standard network protocols such as DeviceNet, PROFIBUS, FOUNDATION fieldbus
and AS-interface have become more widely accepted, it has become possible
to effectively integrate process control components into an industrial
communications network. A network system may comprise a number of
actuated valves fitted with PlantNet Control Monitors interconnected by a
common industrial communications protocol.
The PlantNet Control Monitor is fitted directly onto the pneumatic actuator* and
communicates digitally over a field network.
Each PlantNet Control Monitor on a network is assigned a unique address.
This allows communication with the host, updating valve position via limit
switch inputs and controlling valve position via integral solenoid valve outputs.
In addition, each PlantNet Control Monitor
is able to accept a comprehensive range of discrete external field devices for control, alarm or diagnostic
purposes.
Communications with a PLC or host computer is accomplished by a scanner
card or gateway interface which is compatible with the primary control
network.
* PROFIBUS, FOUNDATION fieldbus, AS-interface and DeviceNet may also be implemented within the
complete Tyco range of electric actuators.
Standard Network Protocols
DeviceNet, PROFIBUS, FOUNDATION
fieldbus and AS-interface have
emerged as accepted standards for
interfacing discreet devices.
They have proved to be extremely
reliable, simple to understand and
consistently cost effective. These two
major network standards readily
integrate with PLC’s and DCS systems
from various manufacturers, through offthe
shelf gateway or scanner interfaces.
The Network Card
Depending upon the network standard
selected (DeviceNet, PROFIBUS,
FOUNDATION fieldbus or AS-interface),
a dedicated network card is integrated
within the enclosure of each PlantNet
Control Monitor.
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