ETIC AFO485, Руководство пользователя, Страница: 11 / 36

AFO485 and RFO485 USER MANUAL ref 9011509-01 Page 11
2.5. Asynchronous Interfaces
At each end, the asynchronous interface used can be different; for
example, the first modem can be linked to the PC using the RS232
interface while the second AFO485 can be connected to a PLC using the
RS485 or RS422 interface.
RS232 Interface
The RS232 interface is available on an RJ45 plug.
The CAB593 cable has a DB9 female connector for the RS232 link.
It must be ordered separately (see appendix 1).
The CD and DSR and CTS signals are closed by the AFO485 as soon as
the modem receives the modulation from the remote AFO485.
No control signal from the RS232 terminal (DTE) is necessary.
RS485 and RS422 interfaces
The unit has a RS422 (4-wire) and RS485 (2-wire) interface on the 6 point
screw block.
These interfaces are not opto-isolated and must be used for short
distances.
The matching resistor of the bus is not included in the product.
The diagrams of these interfaces are given in § 5.5.
2.6. Transmission failure output
The transmission failure output is closed when the modulation of the
remote modem has been detected even if no data is received from the
fibre optics; the line led is lit.
The transmission failure output is opened as soon as the modulation is
no longer received or when the power is off; the line led is extinguished.