Siemens SINUMERIK 840D sl Commissioning Manual page 951

For a safe shut down during a power failure, it takes the PCU approx. 60 seconds. For a
typical power consumption of approx. 60 W, a capacitor-buffered UPS with an energy
storage device of 7.5 kWs is recommended. If longer buffer times are required, then several
expansion modules can be connected in a cascade connection.
Note
Information about the test environment for machine OEMs
The "SITOP UPS" function has been tested in the standard configuration with the operating
software. When installing add-on or OEM software components, the shutdown procedure of
the complete system has to be checked by the user.
For additional information, please refer to the KT10.1 Catalog.
2.4.1 Starting and configuring the SITOP monitor
Windows boot up
The SITOP monitor has to be started by Windows automatically during ramp-up: Activate
this setting when installing the SITOP software in the dialog "Configuration - default settings
for the SITOP Software". Select the option "Start program with Windows". After the PCU has
restarted, the SITOP monitor is then automatically started. The next installation step is to
configure the monitor.
NOTICE
The SITOP monitor must not be started via the Windows Autostart directory.
PCU-Basesoftware (IM8)
Commissioning Manual, 02/2012, 6FC5397-1DP40-3BA0
Configuring the system
2.4 PCU with SITOP UPS module
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