GPD315 Modbus RTU Technical Manual TM 4325
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The function of terminals R+, R-, S+, and S- are described below.
Table 2-1. Functions of Terminals
Terminal Symbol Functions Remarks
S+ RS-485 output (+) Use as output at
S- RS-485 output (-) parallel connection
R+ RS-485 input (+) Us as input at
R- RS-485 input (-) parallel connection
It is important to select an appropriate wire size to prevent voltage drop. The table below
indicates the suggested wire sizes.
Table 2-2. Applicable Wire Size for Terminal Connections
[mm
2
]AWG I[A] VAC[V]
Twisted wire 1.0 16 12 125
Single wire 1.5 16 12 125
UL - 22-16 10 300
CSA - 28-16 10 300
CSA - 28-16 10 150
When stripping the wire, approximately 5.5 mm should be exposed in order to make a good
connection.
Note:
Avoid sources of electric interference capable of inducing noise into the cable.
Communication and signal wiring should be kept separate from power wiring. Four inches should
separate the communications/signal wiring from any low voltage AC or high frequency source.
Ten inches should separate the communications/signal wiring from any high voltage cables. If
communication or signal wiring must cross power wiring, it must cross at a right angle.