Honeywell HPM, Сервисная инструкция

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4 Fault Isolation
4.9 HPMM Alphanumeric Display
R688 HPM High-Performance Process Manager Service 371
December 2020 Honeywell
Failover display sequence (non- Detailed Display mode)
An example of a display sequence for a failover when a RAM parity error occurs with the Detailed
Display mode not invoked is listed in the following table for HPMM 1 and HPMM 2.
Table 78 Alphanumeric Display for Failover HPMM Swapping Sequence (Non-Detailed
Display Mode)
HPMM 1 HPMM 2 Description
OK39 B 40 Run state (UCN node 39)
F139 OK39 HPMM 1 failure
blank
F139 OK39 HPMM 1 failure
blank
The failure pattern repeats and blinks (F139, blank, F139, blank, - - -.)
HPMM Alphanumeric Display Blanking
The HPMM’s Communications processor is the designated owner of the Alphanumeric display and is
responsible for maintaining the display with current information. In the event of a Communications
processor failure, it is undesirable for the alphanumeric display to latch erroneous information. To
prevent this situation from occurring, the alphanumeric display is blanked by the hardware if the
Communications processor Watch Dog Timer (WDT) times out. This covers any ungraceful
Communications processor failures scenarios.
It is possible to override the alphanumeric display blanking by pressing and holding the Detailed Display
switch on the High-Performance Comm/Control card. The information gained by doing this cannot be
guaranteed to be correct or meaningful.
Control processor WDT timeout
In the event of a HPMM Control processor Watch Dog Timer (WDT) timeout, the operation of the
alphanumeric display is unaffected except that the Communications processor displays the appropriate
failure information to indicate that the Control processor’s WDT has timed out.