Siemens C79000 Z7076 C638 04 - Manual (Page 24)

Commissioning the SIMATIC Box PC 620
2-8
SIMATIC Box PC 620 Operating Manual
C79000-Z7076-C638-04
2.3 Preparing for Operation
Connection to the Power Supply Unit
Note
The SIMATIC Box PC 620 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 SIMATIC Box PC 620 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 standard power supply unit of the SIMATIC Box PC 620 is designed for
115/230 V systems.
The power supply unit has automatic mains voltage changeover. It is not
necessary to adjust the voltage span.
Equipotential Measures
Low-impedance ground connections ensure that faults arising from external power
supply cables, signalling cables or cables to peripheral units are diverted.
Therefore connect the equipotential grounding connection on the system housing
to the central earth terminal of the cabinet or the unit, into which the computer is
fitted, in such a way that it has low impedance (large surface area, large contacts).
The minimum cross section should not be less than 5 mm
2 .
The connection is on the side of the device and is identified.by the symbol: