Input/Output Modules
97
Chapter 3
System Description
The PI Module has three independent input channels. Each input channel:
• Receives pulse input voltages from each point
• Converts the values to frequency (RPM) data
• Transmits the values to the MPs on demand
To ensure correct data for each scan, one value is selected using a mid-value
selection algorithm. Sensing of each input point is designed to prevent a single
failure on one channel from affecting another channel.
!
CAUTION
For critical control applications, we recommend using redundant sensors.
The PI Module sustains complete, on-going diagnostics for each channel. If the
diagnostics detect a failure on any channel, the Fault indicator is activated, which
in turn activates the system alarm. The Fault indicator points to a channel fault,
not
a complete module failure. The PI Module is guaranteed to operate properly in the
presence of a single fault and may continue to operate properly with multiple faults.
The PI Module supports hot sparing for online replacement of a faulty module or
continuous back-up to an active module. The PI Module is mechanically keyed to
prevent improper installation in a configured baseplate.
Summary of Contents for Trident
Page 1: ...Trident Version 1 2 Triconex An Invensys Company Planning and Installation Guide ...
Page 10: ...x Contents Trident Planning and Installation Guide ...
Page 16: ...xvi Training Trident Planning and Installation Guide ...
Page 53: ...Main Processor Module 37 Chapter 3 System Description Model 2101 Main Processor Baseplate ...
Page 140: ...124 Covers Trident Planning and Installation Guide ...
Page 216: ...200 Replacing Modules Trident Planning and Installation Guide ...
Page 238: ...222 Diagread Cables and Debug Connectors Trident Planning and Installation Guide ...
Page 240: ...224 Trident Planning and Installation Guide ...
Page 248: ...232 Trident Planning and Installation Guide ...
Page 264: ...248 Glossary Trident Planning and Installation Guide ...
Page 274: ...258 Index Trident Planning and Installation Guide ...