Rs-485 Interface For Card Readers; Rs-485 Data Bus System Conditions - Bosch ADS-AMC2-4R4CF Installation Manual

Access Modular Controller 2
4.11

RS-485 interface for card readers

The AMC2 provides four ports for connecting a maximum of eight readers with RS485
interfaces.
Each interface is connected using a 10-pin pluggable screw connector.
For more information on these connections, refer to Connecting diagrams, page 45 .
Figure 4.17: Location of the RS485 interfaces for readers
The interfaces 1 and 2 build a bus (bus 1) for its own like the interfaces 3 and 4 (bus 2).
All eight possible readers can connect to each of the buses in any combination. However, the
addresses of the readers must be unique on a controller.
The voltage on the interface is equal to the input voltage of the controller.
For more information on the connection of the RS-485 interface, refer to Connecting
diagrams, page 45 .
Notice!
i
If the current consumption on the interface is higher than 1.5A then change the distribution
to the other interfaces or use an external power supply for the reader.
Notice!
i
Damage to the device due to wrong voltage
Make sure that the readers support the same voltage as the power supply unit that is
connected to the AMC. Readers that do not support the same voltage will be damaged.
Refer to
–
4.11.1

RS-485 data bus system conditions

The following conditions apply for an RS-485 bus system:
–
–
–
–
–
–
–
–
Bosch Security Systems B.V.
3
BUS 2
BUS 1
1
Connecting diagrams, page 45
A bus system consists of a bus line and/or one or more branch lines.
Cable lengths exceeding 100 m (300 ft) must be installed as bus lines.
Branch lines are branching connections from a bus line.
Peripheral devices are card reader which are connected to the AMC2.
Maximum cable length of a bus line must not exceed 1200 m (4000ft).
The cable length of branch lines must not exceed 100m (330ft).
For the wiring of the bus system use twisted pair cable.
Any bus line conductor connects up to eight card readers. Do not exceed the maximum
number of devices.
4
2
Installation manual
Installing | en 27
2022-03 | V03 |