S7 F System, Monitoring Errors - Siemens SIMATIC S7 F Manual

Getting Started
2.2.5

S7 F System, Monitoring Errors

Removing the Front Connector
1. Remove the front connector of the SM 326F DI24xDC24V.
You have triggered an error at the SM 326F DI24xDC24V. The SF LED comes
on and the SAFE LED goes out. The EXTF LED of the CPU comes on, but the
CPU remains in RUN.
2. Go into the diagnostic buffer of the CPU (PLC > Module Information >
Diagnostic Buffer). The signal module with the address 8 is reported as
defective, but because OB82 is present, the diagnostic interrupt does not result
in CPU stop.
3. You can read out detailed information on defective modules by choosing PLC
> Hardware Diagnostics. Double-click DI 24 in the open ONLINE hardware
configuration, and look at the diagnostic buffer in the module state.
4. Go to the "F blocks" CFC chart, and switch to test mode. The QBAD output of
the F_CH_DI F channel driver blocks are set to TRUE: There is an error.
QUALITY=16#48 indicates that there are substitute values at Q output.
5. Now insert the front connector in the SM 326F DI24xDC24V again. After a
reintegration time of approx. 1 minute, the SAFE LED comes on again and the
SF LED goes out. The EXTF LED on the CPU goes out.
The module is reported as OK in the diagnostic buffer of the CPU.
In test mode you can still see that the driver block is reporting an error: If, for
example, you apply voltage at terminal 5 for input 8.0, the Q output of the
driver block remains at 0. The SM 326F DI24xDC24V must therefore be
reintegrated first: The ACK_REQ=1 output requests an acknowledgment at the
fail-safe ACK_REI input.
6. In our case, you can output a signal of 1 for one cycle via the F_QUITES F FB,
whose input can be connected to a non-fail-safe engineering system (ES).
Double-click the IN input, and enter the value 6; then double-click (within a
minute) IN again, and enter 9 - you can also use the Apply button - (see
Chapter 8, Fail-Safe Function Blocks F_QUITES). The driver block now no
longer reports an error, and the Q output changes from 0 to 1.
Additional Errors
Trigger the following two errors, and display the diagnostic buffer of the CPU:
•
Interruption in the PROFIBUS connection
•
Remove and insert the SM 326F DI24xDC24V
Then reintegrate the signal module again.
2-12
Fail-Safe Systems
A5E00085588-03