Mounting with installation instructions
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3.3 Grounding concept
3.3.1 Power supply
The Compact Reader is contained within a plastic housing and is not grounded.
If a Compact Reader is operated with an ungrounded power supply, then neither the power
supply nor the peripheral device is grounded
If a Compact Reader is operated with a grounded power supply, only the power supply is
grounded
3.3.2 Communication connections
3.3.2.1 RS-485 connection
The shieldings of the RS-485 cables are not grounded, but are instead attached to
the C (common) connection at the Compact Reader and the connected devices.
With bus cabling for the communication connections, please also ensure that there is a continuous
connection between the shielding of the RS-485 line and the stubs.
3.4 Installation instructions for the power supply
A distinction is made between central and local power supply.
3.4.1 Central power supply
Power is provided by 1 central supply.
For information on max. cable lengths, see Chapter 3.2.1/Page 23
3.4.2 Local power supply
The local power supply is used where increased requirements are placed on the Compact Reader
in terms of operational reliability. A separate power supply unit is used for this purpose.
For information on max. cable lengths, see Chapter 3.2.1/Page 23