19
A SP M E T ER SP L I T CO R E
—
ASPMETER split core
Connect 2-wire or 4-wire Modbus RS-485 daisy chain network
(Figures 1 and 2).
Figure 1.
Figure 2.
1. Mechanically secure the RS-485 cable where it enters
the electrical panel.
2. Connect all RS-485 devices in a daisy-chain fashion,
and properly terminate the chain (Figure 3).
Figure 3.
3. Shield the RS-485 cable using twisted-pair wire, such as
Belden 1120A. The cable must be voltage-rated for the
installation.
4. When tightening terminals, ensure that the correct torque
is applied: 0.5 to 0.6 N·m (0.37 to 0.44 ft·lb) for connectors
on main board, 0.22 to 0.26 N·m (0.16 to 0.19 ft·lb) for
connectors on adapter boards (Figure 4).
Figure 4.
WARNING: After wiring the RS-485 cable, remove all
scraps of wire or foil shield from the electrical panel.
Wire scraps coming into contact with high voltage
conductors could be DANGEROUS!
Power must be disconnected and locked out before
making any wiring connections.
Wiring
SHIELD
RX- TX-
RX+ TX+
TX-
TX+
2-wire
Master or Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHIELD
4-wire
Master
Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
2-wire example
–
+
Belden 1120A or
equivalent
120 Ω terminator
on last device of
daisy chain
Not Used
–+
SHIELD
RX- TX-
RX+ TX+
TX-
TX+
2-wire
Master or Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHIELD
4-wire
Master
Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
2-wire example
–
+
Belden 1120A or
equivalent
120 Ω terminator
on last device of
daisy chain
Not Used
–+
SHIELD
RX- TX-
RX+ TX+
TX-
TX+
2-wire
Master or Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHIELD
4-wire
Master
Slave
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
SHLD
TX+
TX+
RX+
TX–
TX-
RX-
SHIELD
2-wire example
–
+
Belden 1120A or
equivalent
120 Ω terminator
on last device of
daisy chain
Not Used
–+
