GE PACSystems RX7i

Chapter 9. Diagnostics
394 PACSystems* RX7i, RX3i and RSTi-EP CPU Programmer's Reference Manual GFK-2950C
9.3.2 Using Fault Contacts
Fault (-[F]-) and no-fault (-[NF]-) contacts can be used to detect the presence of I/O faults in the
system. These contacts cannot be overridden. The following table shows the state of fault and no-
fault contacts.
Condition
[F]
[NF]
Fault Present
Fault Absent
ON
OFF
OFF
ON
An NF contact will be ON (F contact will be OFF) when the referenced I/O point is not faulted, or the
referenced I/O point does not exist in the hardware configuration.
Fault Locating References (Rack, Slot, Bus, Module)
The PACSystems CPU supports reserved fault names for each rack, slot, bus, and module. By
programming these names on the FAULT and NOFLT contact instructions, logic can be executed in
response to faults associated with configured racks and modules.
Fault Locating Reference Name Format
These fault names can only be programmed on the FAULT and NOFLT contacts. The reserved fault
names are always available. It is not necessary to enable a special option, such as point faults.
Fault
Reference Type
Reserved
Name
Comment
Rack
#RACK_000r
Where r is rack number 0 to 7.
Slot
#SLOT_0rss
Where r is rack number 0 to 7 and
ss is slot number 0 to 31.
Bus
#BUS_0rssb
(Genius only)
Where r is rack number 0 to 7,
ss is slot number 0 to 31, and
b is the bus number (1 or 2).
Module
#M_rssbmmm
(Genius only)
Where r is rack number 0 to 7,
ss is slot number 0 to 31,
b is the bus number (1 or 2), and
mmm is the Bus Address number 000 to 255.
These fault names do not correspond to %SA, %SB, %SC, or to any other reference type. They are
mapped to a memory area that is not user-accessible. Only the name is displayed.