Instruction manual

COM32 INSTALLATION & OPERATION MANUAL 11
Installation and Operation
Figure 2.3a RS-485 Straight-Line and Loop Topologies
SHLD
SHLD
RS-485 Cable
AWG 22 shielded twisted pair. Overall length: 4000 ft. maximum.
SHLD
SHLD
SHLD
RS-485 PORT RS-485 PORT
SHLD
RS-485 PORT
SHLD
SHLD
R
T
RS-485 Cable
AWG 22 shielded twisted pair. Overall length: 4000 ft. maximum.
SHLD
SHLD
SHLD
SHLD
R
T
R
S
-485
S
TRAI
G
HT-LINE T
O
P
O
L
OG
Y
RS-485 LOOP TOPOLOGY
RS-485 PORT RS-485 PORT
RS-485 PORT
RS-485 PORT RS-485 PORT
RS-485 PORT
RS-485 PORT RS-485 PORT
RS-485 PORT
Termination Resistor
See Section 3.2.3.
SHLD
Last
RS-485 Device
(End Point)
Last
RS-485 Device
(End Point)
Termination Resistor
See Section 3.2.3.
Computer
or Modem
SHLD
COM32
RS-232C to RS-485 Converter
RS-232C
RS-485
Computer
or Modem
COM32
RS-232C to RS-485 Converter
RS-232C
RS-485
SHLD