Specifications

MEGAPOWER CPU 8200-0421-01, REV. E
INSTALLATION AND SERVICE GUIDE
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Appendix A: Hot Switch Setup
The following applies when two MPCPUs connect
together for redundancy.
Selected Unit. Since both MPU modules are
actively processing incoming data, the term
“selected” identifies which unit is driving the lines.
Backup Unit. An MPU module whose CPU is not
driving AD data lines and RS-232 COM ports.
However, it is still actively processing incoming
data so it can hot switch over if the selected unit
fails.
UP arrow in message center. Indicates an
MPCPU with AD data lines 1–2 and RS-232 COM
ports 1–16 selected.
DOWN arrow in message center. Indicates an
MPCPU with AD data lines 3–4 and RS-232 COM
ports 17–32 selected.
Appendix B: Detaching the MPU
from the Port Module
1. Loosen the thumbscrew in the back of the
assembly.
2. Push the MPU module away from the Port
module, detaching it from the blind connector.
3. Remove the MPU module.
Thumbscrew
MPU
Module
Port Module