Io Device Diagnostics; Reading Out The Diagnostics Information With Step 7 - Siemens SIMATIC MV540 H Operating Instructions Manual

Service and maintenance
10.1 Error and diagnostics messages
10.1.7

IO device diagnostics

Errors, for example, "Error - transfer error PROFINET IO connection error", trigger I/O device
diagnostics. The diagnostic information is read out using STEP 7 depending on the I/O
controller.
How to read out I/O device diagnostic information and how it is structured is described briefly
below. You can find a detailed description in the programming manual "PROFINET IO –
From PROFIBUS DP to PROFINET IO".
10.1.7.1

Reading out the diagnostics information with STEP 7

If, for example, the error "Error - transfer error PROFINET IO connection error" occurs on the
optical reader and you are using an S7 controller as the I/O controller, the diagnostic
interrupt OB (OB82) is started on the I/O controller.
The local variables "OB_82_EV_CLASS", "OB_82_MDL_DEFECT" and "OB82_EXT_FAULT"
of the OB have the following values:
Table 10- 7
Variable
OB_82_EV_CLASS
OB_82_MDL_DEFECT
OB_82_EXT_FAULT
Unfortunately, you cannot identify the actual cause of the problem in the local variables of
OB82. You can determine this with PROFINET IO by calling SFB 54 "RALRM" in OB 82. The
entry "Faulty module" appears in the diagnostic buffer and the corresponding text from the
GSD file, for example, "Error - transfer error PROFINET IO" appears in the module
information of the optical reader.
When the error has been corrected and you have acknowledged this in the WBM of the
optical reader, the diagnostics interrupt OB (OB 82) is restarted on the I/O controller.
The local variables "OB_82_EV_CLASS", "OB_82_MDL_DEFECT" and "OB82_EXT_FAULT"
of the OB have the following values:
Table 10- 8
Variable
OB_82_EV_CLASS
OB_82_MDL_DEFECT
OB_82_EXT_FAULT
The entry "Module OK" now appears in the diagnostics buffer. The text from the GSD file
relating to the previous error no longer appears in the module information of the optical
reader.
188
Tags of the diagnostic interrupt OB (OB 82) in the event of an error
Value
B#16#39
TRUE
TRUE
Tags of the diagnostic interrupt OB (OB 82) after error correction
Value
B#16#38
FALSE
FALSE
Meaning
Event entering state
Module problem
External problem
Meaning
Event exiting state
No module problem
No external error
Operating Instructions, 06/2018, C79000-G8976-C494-01
SIMATIC MV500