Honeywell LC13-510 Manual page 69

B.6 REDUNDANT MODULE REPLACEMENTS
1. This section applies only to a redundant Network Interface Module (NIM), Hiway
Gateway (HG), or Programmable Logic Controller Gateway (PLCG).
2. Determine in which unit, the primary or secondary, you want to perform the
replacement first. The recommended procedure would have you replace the processor
in the primary unit first. This will require that you fail-over the primary to the
secondary, making the primary available and allowing you to confirm good operation
of both units. It is acceptable to perform the replacement to the secondary first, but you
will not have validated the secondary's good operation prior to the board changes. In
either case, you must be certain that the intended unit is the backup. When it is
necessary to cause an intentional fail-over, follow the procedure below:
At a Universal Station, perform a Shutdown to the intended unit. This will cause an
"orderly" shutdown to the "POWER ON" condition and notify all nodes that the unit is
being shut down, as well as cause the backup to take over as the active unit. If the
backup, now the active primary, has successfully performed the "takeover," you are
ready to proceed to subsection 1.7, step 2, below. When subsections B.7 through
B.10 are completed on the first unit, repeat them on the second unit.
B.7 DISASSEMBLY
1. If the node is "ON LINE," go to a Universal Station and execute a shutdown to the
intended unit. This will perform a "controlled" shutdown to the "POWER ON"
condition and notify all nodes that the unit is being shut down.
2. Place the ac power switch on the front of the module in the OFF position.
3. Remove the front cover by removing the screws and swinging the right side of the
cover out 1 inch and then pulling it out to the right.
4 Be sure to observe proper ESD prevention practices, especially while handling boards
during the following steps, including subsection B.9, Reassembly.
5. Remove the K2LCN board from Slot 1 at the front of the module.
6. At the rear of the module, remove the LCN A and B coax cables from the LCN I/O
card, one at a time, by removing the T- connector from the board and not by removing
either cable from the T- connector. Make sure the system is still operational on both
cables as it was prior to this step. Remove the LCN I/O card from Slot 2.
If the module is a single remote node connected with an LCNFL, the LCNFL must be
removed and checked to see if it is revision F (or later). If it is earlier than revision F,
an LCNFL with revision F (or later) must be obtained.
Dual Node Module Service B-3
B.6
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