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IPEX
(IP Electronix)
PH485iX
:
User’s Manual
Page 10 of 12
Doc No. : PH485iX-UM-001
21 August 2019
9.
RS-485 Connecting Methods
According to the signal labels on the device, the RS-485 signals are: D+(A) and D-(B) that their connections are as
below:
9.1)
RS-485: Point to Point Connection
9.2)
RS-485: Multipoint Network
NOTICE 1:
Normally, D+ connects to D+, and D- connects to D-; but in some devices, D+ and D- signals are vice-
versa, so you should connect D+ to D- and D- to D+ in these cases.
NOTICE 2:
In noisy environments, it is better to use GND signal too.
RS-485 Cable:
The best cable type for RS-485 side is shielded twisted pair. CAT5 or CAT6 cables are good
choices. Maximum cable length could be 1200m. Connect D+ and D- pins to one pair and GND signal to shield.
Terminator-Resistor:
A 120Ω Terminator-Resistor is installed internally and further external Terminator-Resistor
is NOT REQUIRED.
