5-8
PACSystems* RX3i
PROFINET Controller Manual
– December 2011
GFK-2571A
5
PROFINET IO Alarms
PROFINET IO uses Alarms to transfer indications of changes or problems in the remote IO-Device.
For example, Diagnosis Alarms are used to indicate a problem with a channel such as a short circuit,
a blown fuse, or overtemperature condition. The PNC translates PROFINET alarms into CPU faults
for the RX3i CPU. The illustration below shows what happens when a problem is detected on one of
the channels of a module within a remote IO-Device, in this case, a VersaMax PROFINET Scanner.
IO-Device
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3
1
1. The PROFINET Controller establishes
Application Relationship (AR) and then
Alarm Communication Relationship (CR)
with IO-Device
2. Module detects a problem (such as short-
circuit) and reports it to IO-Device
(PROFINET Scanner).
3. IO-Device sends Alarm to PROFINET
Controller via Alarm CR.
4. PROFINET Controller logs fault in the
Local Log and the RX3i CPU fault table.
5. PROFINET Controller sends Alarm ACK
to IO-Device via Alarm CR.
RX3i CPU Node with
PROFINET Controller
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PROFINET Alarm Action
If a PROFINET I/O Alarm occurs, the action is Diagnostic (the action type is not configurable). When
a fault in this group is processed, the CPU sets the following status bits: #ANY_FLT, #IO_FLT,
#IO_PRES, and #PNIO_ALARM (%SA30).
The #PNIO_ALARM status bit is cleared when the I/O fault table is cleared.