Siemens SINUMERIK 840C - Manual (Page 1129)

12 Functional Descriptions 01.99
12.35 Uninterruptible power supply (UPS) (as from SW 6.3) (Express shutdown)
12.35 Uninterruptible power supply (UPS) (as from SW 6.3)
(Express shutdown)
General
When the 840 C control is not purposely, i.e. properly ramped down but instead just turned off,
general problems can occur in the operating system. E.g. opened data files may not be closed
properly leading to inventory data inconsistencies. In a worst case scenario, the file system of
the hard disk could become inconsistent during a momentary write access to the hard disk.
The danger in such cases is that the MMC may not be able to boot at the next POWER ON.
With the help of a standard UPS (approx. 300 W) it is possible to switch off or ramp down
(express shutdown) the NC in a controlled manner.
Express shutdown function diagram
UPS signals
”Power failure”
Input X 121 5/6
UPS
CSB
I/O
NCK
MD 5030
Bit 0 - bit 7
MMC
PLC
basic
program
Bit 6 Bit 7
FY 22
PLC
user
program
I/O
FX 73/74
I code
express
shutdown
Message
to USP
”Data saved”
Output
X121 24/25
Configuration of the express shutdown
Configuration options as follows:
Connection via special I/O on the central service board (CSB)
Connection via PLC inputs/outputs
12–354 © Siemens AG 1992 All Rights Reserved 6FC5197- AA50
SINUMERIK 840C (IA)