Preparing For Operation - Siemens SIMATIC Rack PC 840 Manual

Setting Up and Operating the SIMATIC Rack PC 840
3.3

Preparing for Operation

Connection to the Power Supply Unit
Power Supply Unit
Figure 3-3 Connection to the Power Supply Unit
Warning
!
The Rack PC with AC power supply is equipped with a safety-tested mains cable
and may only be connected to a grounded grounding outlet.
Make sure that the socket on the device or the grounding outlet of the building
installation is easily accessible and as near as possible to the device.
The Rack PC has no mains switch. The mains plug must be pulled out for
complete mains separation. This point must be easily accessible.
If the PC is installed in a cabinet, there must be a central mains disconnector.
The AC power supply unit is designed for 120/230/240 V systems. The power
supply unit has a long-range input. It is not necessary to adjust the voltage span.
The DC power supply unit is designed for 24V systems.
Warning
!
Only connect the device to 24V DC power supply systems which meet the
requirements of a safe extra-low voltage (SELV); in addition, a protective
conductor must be connected.
The cable cross section has to be adapted to the short circuit current of the 24V
DC power supply unit so that the cable does not cause damages in the event of a
short circuit. Cables with a cross section of a maximum of up to 5 mm
connected.
Optionally, one of these power supplies is installed.
3-6
2
can be
SIMATIC Rack PC 840 Manual
A5E00104826-03