2.2.2 End Of Line Termination Switch For The Modbus Rs -485 Port On The Gw-Bac1; Figure 4: Modbus Rs-485 End-Of-Line Termination Switch On The Gw-Bac1 - Unitronics GW-BAC1 User Manual

Unitronics's BACnet Gateway User Guide

2.2.2 End of Line Termination Switch for the Modbus RS -485 port on the GW-BAC1


On long RS-485 cabling runs, the RS-485 trunk must be properly terminated at each end.

The GW-BAC1 has an End Of Line (EOL) blue jumper. The default setting for this Blue EOL switch is OFF
with the jumper straddling the pins closest to the inside of the board of the GW-BAC1.
o
On short cabling runs the EOL switch does not to need to be turned ON.

If the GW-BAC1 is placed at one of the ends of the trunk, set the blue EOL jumper to the ON position
straddling the pins closest to the outside of the board of the GW-BAC1.

Always leave the single Red Jumper in the A position (default factory setting).

Figure 4: Modbus RS-485 End-Of-Line Termination Switch on the GW-BAC1

Unitronics
Modbus RS-485 EOL Switch
Leave in A Position
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