metso automation maxPAC - Remote I;O and Bus Extension

maxPAC Input/Output Subsystem
Metso Automation MAX Controls Inc. • 277596 •
1-15
inactive DPU also continuously updates its analog output modules with current
values so that bumpless transfer occurs when the inactive DPU becomes
active.
Redundant network
I/O Bus
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Backup
Adapter
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I/O Bus
Common I/O Bus
Figure 1-8. Mixed Configuration
Remote I/O
A Bus Expander Module (BEM) permits the I/O bus to be extended up to
2,000 meters using highly reliable and noise immune fiber optic cables.
BEMs, configured in pairs, support both locally and remotely mounted I/O
cards. In a typical configuration using redundant Distributed Processing
Units (DPUs), an I/O cabinet installed locally in a control room contains I/O
modules, a DPU pair, and a BEM pair. This is connected via I/O optical
cable to a ruggedized remote cabinet containing I/O modules, and a second
BEM pair. The optical link is established between the local and remote