Siemens 670 V2, Руководство по эксплуатации

Страница: 41 / 106

Connecting
6.2 Connecting a decentralized design
Panel PC 670 V2/870 V2, Control unit
6-4
Operating Instructions, Edition 03/2004, CD Documentation and Drivers
Note
Make sure that the cable strain reliefs for the connection cable at the operating unit and
computer unit are mounted properly, especially if the devices are installed at a slant.
Power supply
120-240 V AC
Socket for
interconnecting cable
to transmitter
Receiver
Mounting plate
for receiver and direct key module Operating unit
(rear) Fastening screw
for mounting plate
USB cable Direct key module (optional)
Figure 6-2 Back side of the control unit with attached remote module and direct key module
6.2.3 Equipotential bonding
Differences in potential
Differences in potential arise between separated system parts, which in some cases leads to
high equalization currents. When cable shields are applied on both sides and are grounded
at different system parts, for example.
Causes of potential differences are different network feed-ins, for example.