|
|
The architecture of the WDPFII communication system permits
all drops on the WDPFII Data Highway to have transparent access
to any other drop's process point values without communications
overhead. Each drop on the Data Highway is a sophisticated
microprocessor capable of a large array of independent functions.
Drops can be added as needed to expand the capability of the
system over its entire life, therefore a host computer is
not required with this configuration. Drops may also be added
to an existing system without changing the configuration of
the drop.
The Westnet II data highway provides the real-time
communications infrastructure through which the plant process
is controlled. It connects the Distributed Processing Units
to operator stations as well as other functional devices such
as historians, loggers and communication servers. In fact,
the WDPFII data highway is uniquely designed to handle one
millisecond sequence of events (SOE) distributed across the
system. Westinghouse Process Control designed this high-speed
data communication system to be unaffected by any amount of
plant activity. One dual highway network can service the needs
of an entire plant. The deterministic nature of this highway
ensures that information acquired by one drop is passed to
6/13/07slot. This prevents overburdening
the system, which deteriorates system response possible with
probabilistic or layered-network designs from other vendors.
Westnet II Data Highway provides one-second updates of all
plant variables. Unlike other highways, Westnet II permits
transparent access for all processors on the highway to process
information on other highways, without additional communications
overhead.
The Ethernet Information Highway is WDPFII's open-system
network which supports file and non-time-critical data transfers.
The Ethernet interconnects all WEStations and sends data between
WDPFII and other plant information networks. On Ethernet,
file or message transmission is made possible without loading
Westnet II Data Highway. The Ethernet Information Highway
can be securely extended via a bridge to local or wide-area
networks. This extension allows the WDPFII distributed control
system to pass all variables, both real-time and non-real-time,
and process graphic displays from the WDPFII system to the
LAN or WAN. For controlled access, multiple layers of security
may be administered through a WEStation. Linking the plant's
control and administrative data bases allows users to combine
pertinent real-time control data with resource, production,
and geographic information.
Highway Features:
- Deterministic nature of Westnet II ensures information
acquired by one drop is passed to other stations.
- Westnet II provides one-second updates of all plant variables.
- Westnet II permits transparent access for all processors
on the highway to process information on other highways.
- Expansion accommodates up to 254 drops per highway, on
the Westnet II data highway.
- Ethernet has capabilities to be securely extended via
a bridge to local or wide-area networks.
- Ethernet allows the WDPFII DCS to pass all variables,
both real-time and non-real-time, and process graphic displays
from the WDPFII system to the LAN or WAN.
- Standard packaging for the Ethernet highway includes a
single connection through the primary RISC processor. An
optional redundant Ethernet connection can be supported
through a VME-based board.
Download WDPF® System Highways PDF
|
