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4-2 How to Wire to Host Device
4-13
(2) 1:N connection with link unit
To connect an antenna and host device through RS-422A/485, use the link unit. An example below shows the connection of several
antennas and one host device through RS-485 (2-wire).
Correct Usage
Turn ON (connected) the terminating resistances at both ends of the entire RS-422A/RS-485 communication wiring.
Microwave
antenna
Station No.
00
Link unit
RS-422A/485 link unit
connecting cable
Host device
24 VDC
ground-
ing
Host device set-
ting
* RS-485
(2-wire)
* Terminating
resistance ON
Link unit setting
* RS-485
(2-wire)
* Terminating
resistance
OFF
Microwave
antenna
Station No.
01
Microwave
antenna
Station No.
31
24 VDC
ground-
ing
24 VDC
ground-
ing
Link unit
Link unit
Link unit setting
* RS-485
(2-wire)
* Terminating
resistance
OFF
Host device set-
ting
* RS-485
(2-wire)
* Terminating
resistance ON
A maximum of 32 units can be connected