Connection To The Power Supply Unit - Siemens SIMATIC RACK PC 840 Getting Started

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Connection to the Power Supply Unit

Caution
!
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 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 of the Rack PC 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 of the Rack PC is designed for 24V systems.
Warnung
!
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
Optionally, one of these power supplies is installed.
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
2
5 mm .
The connection is on the rear of the device and is identified by the symbol:
Before you connect the Rack PC to the mains, the keyboard, mouse or monitor must be connected.
1. Insert the connector cable of these peripheral units into the corresponding sockets on the port side
of the Rack PC.
2. Once the peripheral units have been connected, the device is ready for operation from the power
supply. Connect the device to the mains; the yellow Power LED at the front lights up. The Rack PC
is now in standby mode.
Getting Started Rack PC 840
A5E00104828-04
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can be connected.
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