INTRODUCTION
FEATURES
WBPEEUI250016A1
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The NPM module is a single printed circuit board that occupies
the slot adjacent to the NIS module in the module mounting
unit. The circuit board contains microprocessor based commu-
nication circuitry that enables it to interface with the NIS mod-
ule and all Controlway modules.
Two latching screws on the NPM module faceplate secure the
module in the module mounting unit. The faceplate contains
eight CPU LEDs, a status LED, and a stop/reset pushbutton.
The NPM module has three card edge connectors for external
signals and power (P1, P2 and P3). Connector P1 connects to
common (ground), +5 VDC power, and the Controlway. Con-
nector P2 connects the NPM module to the NIS module. Con-
nector P3 provides for communication between primary and
backup process control unit interfaces. The NPM module com-
municates with the NIS module within its process control unit
through the I/O expander bus.
FEATURES
The process control unit interface has the following features:
•
INFI-NET provides a plant wide communication network.
•
INFI-NET provides time synchronization across the control
system plant wide.
•
Each node, depending on configuration, can operate inde-
pendently of other INFI-NET nodes.
•
The process control unit interface modules provide local-
ized start-up/shutdown on power failure without operator
intervention.
•
The ten-megabaud communication rate gives timely infor-
mation exchange.
•
The NPM module packages process information for maxi-
mum transmission efficiency.
•
The process control unit interface modules handle four
message types: broadcast, time synchronization, multicast
and NIS poll.
•
All messages contain cyclic redundancy check codes (CRC)
and checksums to insure data integrity.
