AERCO Modbus Communications Manual - Manual (Page 65)

Chapter 4
MODBUS
Communication GF-114
Hardware Setup & Installation USER MANUAL OMM-0035_0C
05/18/12 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 • Ph: 800-526-0288 Page 65 of 200
Figure 4-7: I/O Box RS485 COMM Terminal Connections
Connect 120 OHM, 1/2
Watt resister between
+ and – RS485
terminals on the LAST
C-More Box.
I/O PC
Board
NOTE
Do not terminate the shields
of the RS485 leads to the
ground (GND) terminal. The
shields must be terminated
at the source ends only.
Connect the shields of the
incoming and outgoing
RS485 leads together.