Electro Industries/GaugeTech
Doc # E107706 V1.25 5-10
The Unicom 2500 can be configured for either 4-wire or 2-wire RS-485 connections. Since the
Nexus uses a 2-wire connection, you need to add jumper wires to convert the Unicom 2500 to
the 2-wire configuration.
As shown in Figure 5.9, you connect the "RX-" and "TX-" terminals with a jumper wire to make
the "-" terminal, and connect the "RX+" and "TX+" terminals with a jumper wire to make the "+"
terminal
Figure 5.8: Unicom 2500 with Connections Figure 5.9: Detail of “Jumpers”