AERCO ProtoNode Gateway Rev 3 (with external LEDs) - Manual (Page 18)

AERCO ProtoNode Gateway
User Manual
Page 18 of 126 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, NY 10913 OMM-0080_0H
11/06/2014 Ph.: 800-526-0288 GF-129
Figure 3-4: Modbus RS-485 Biasing Jumpers on the ProtoNode RER (Left) and
ProtoNode LER (Right)
3.3.3 End of Line Termination Switch for the Modbus RS-485 port on the
ProtoNode
• On long RS-485 cabling runs, the RS-485 trunk must be properly terminated at each
end.
• If the ProtoNode is placed at one of the ends of the trunk, you place the Blue RS-485
End-of- Line terminating jumper to ON position.
• On short cabling runs the terminating EOL jumper can remain OFF except when an RS-
232 to RS-485 converter is connected to the HOST (AERCO) port. In that case, put the
terminating jumper in the ON position. The default setting for this blue terminating
jumper is OFF.
• Always leave the single Red Jumper in the A position. NEVER move the single
Red jumper.
FIGURE 3-5: Modbus RS-485 End-Of-Line Termination Jumpers on the ProtoNode
RER (Left) and ProtoNode LER (Right)
RS-485 Bias Switch
Leave in A
position
Leave in A
position
Modbus RS-485
EOL Jumper
Modbus RS-485
EOL Jumper