Specifications

Glossary
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process I/O
An Advantys STB I/O module designed for operation at extended temperature
ranges in conformance with IEC type 2 thresholds. Modules of this type often feature
high levels of on-board diagnostics, high resolution, user-configurable parameter
options, and higher levels of agency approval.
process image
A part of the NIM firmware that serves as a real-time data area for the data exchange
process. The process image includes an input buffer that contains current data and
status information from the Island bus and an output buffer that contains the current
outputs for the Island bus, from the fieldbus master.
producer/consumer model
In networks that observe the producer/consumer model, data packets are identified
according to their data content rather than by their node address. All nodes listen on
the network and consume those data packets that have appropriate identifiers.
Profibus DP
Profibus Decentralized Peripheral. An open bus system that uses an electrical
network based on a shielded 2-wire line or an optical network based on a fiber-optic
cable. DP transmission allows for high-speed, cyclic exchange of data between the
controller CPU and the distributed I/O devices.
R
reflex action
A simple, logical command function configured locally on an Island bus I/O module.
Reflex actions are executed by Island bus modules on data from various Island
locations, like input and output modules or the NIM. Examples of reflex actions
include compare and copy operations.
repeater
An interconnection device that extends the permissible length of a bus.
reverse polarity protection
Use of a diode in a circuit to protect against damage and unintended operation in the
event that the polarity of the applied power is accidentally reversed.