Revision: 3.0
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RS-485 Side (DB-9 Male Connector / Terminal Block):
DB-9 Pin:
1
3
5
9
6,7
Terminal Block:
A+
B-
GND
+5V
Jumper (120)
Function:
RS485+ RS485-
GND
Optional +5V
DC input
Terminate/remove Jumper 120 to
turn ON/OFF the 120Ω end-of-line
terminator
•
The numbers on the left indicate the pin assignment of DB-9 male connector
(RS-485 side).
•
The unit will function correctly only when the voltage on +5V pin is around
+5VDC (when RS232 port is connected). Otherwise, please check the
connection. External 5VDC regulated power supply is accepted.
•
The unit comes with a built-in selectable 120Ω end-of-line terminator;
connect it when the data rate is over 19.2kbps or the RS-485’s distance
exceeds 660ft (200m).
■
CONNECTIONS
■
120-OHM END-OF-LINE TERMINATION
Turn on the 120Ω end-of-line terminator on both ends of the RS-485 bus when the data rate is
over 19.2kbps or the RS-485’s distance exceeds 660ft (200m).
