09.95
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SINUMERIK 840C (IA)
3.5 PLC diagnostics
The following diagnostics displays exist:
Displayed by Brief description
1 LED CPU hardware fault
2 – System initialization program
3 USTACK
detailed error
coding
Displays programming errors
4PLC status Displays and changes (password) to PLC data
(I, O, F, D, T, C)
5 Timeout Timeout analysis of write access
3.5.1 LED display
After switching on the mains voltage, the interface control runs a self-diagnostics
program. This program tests the most important hardware components and initiali-
zes the software required for continuing system start up.
If errors in the system are recognized, the LED on the front plate displays the
error.
For a detailed error list, please refer to the “SINUMERIK 840C, Diagnostics
Guide”.
3 PLC Installation
3.5 PLC diagnostics