© 2020 Carrier
13
5
INTERFACING MB485ETH-CG TO DEVICES
5.1
Device Connections to MB485ETH-CG
The MB485ETH-CG has a 3-pin Phoenix connector for connecting RS-485 devices on the R1 port. See
specific device bulletins for details on how to properly connect Modbus to each.
NOTE: Use standard grounding principles for RS-485 GND.
5.2
Wiring Field Port to RS-485 Serial Network
•
Connect the RS-485 network wires to the 3-pin RS-485 connector on the R2 port. (
o
Use standard grounding principles for RS-485 GND
•
See
Section
for information on connecting to an Ethernet network.
Device Pins
MB485ETH-
CG Pin
Label
Pin
Assignment
RS-485 +
TX+
RS-485 +
RS-485 -
RX-
RS-485 -
RS-485 GND
GND
RS-485 GND
BMS
Wiring
MB485ETH-
CG Pin
Label
Pin
Assignment
RS-485 +
+
RS-485 +
RS-485 -
-
RS-485 -
-
GND
RS-485 GND
Figure 7: Connection from MB485ETH-CG to RS-485 Field Network
G
-
+
Figure 6: RS-485 Connections from Devices to the MB485ETH-CG
G
-
+