Siemens SINUMERIK 840D sl Commissioning Manual page 804

System settings
1.3 System booting
1.3 System booting
Sequence
To ensure unproblematic booting of the NCU, the CompactFlash Card must be inserted.
When the NCU is booting up, visual information on the current operating system is provided
using the following displays:
● The RDY-LED flashes slowly orange when the CF card is accessed.
● During booting, the 7-segment display outputs different codes that indicate, for example,
When the booting has been completed successfully, the following is displayed:
● The PLC LED lights up green.
● The 7-segment display shows "6." with a flashing dot.
● The RDY-LED lights up green. All other LEDs are not illuminated.
Performing a reset operation
The reset button is located behind the blanking plate of the NCU.
A reset operation resets the entire system and requires a system restart. This is comparable
to a "Power On reset" except that the 24 V power supply does not have to be switched off.
Booting for servicing purposes
For service or diagnosis purposes, the NCU can be booted from a service system, the
Emergency Boot System.
See also
How do you create a service system for the NCU? (Page 59)
8
when the BIOS is started, when the CompactFlash Card is accessed, etc.
Commissioning Manual, 03/2013, 6FC5397-1DP40-3BA1
NCU operating system (IM7)