Cutler-Hammer D320 PLC, User Manual

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D320 PLC User's Manual
•
The line ground (LG) terminal has electric potential. When the frame ground (FG) is
connected to a solid earth ground, you must also earth ground the LG terminal to prevent
electric shock from the electric potential difference between the two grounds.
•
If the PLC system is not earth grounded, the LG and FG terminals must be kept separate to
prevent ground loops in the power supply system.
120/240 VAC Power Supply Wiring Diagram
Right Wrong
PLC
Other
device
Other
device
PLC
If the noise effect is large, use
an isolation transformer.
Use 14 AWG or thicker
twisted cable.
Breaker
Power supply
I/O module
Control power
(24 V)
Power
Connect alarm output
emergency stop circuit.
Control power
(24 V)
You can supply 24 V power to the I/O
modules. Do not connect 24 V
parallel with other power sources.
LG
FG
24V(+)
24V(-)
COM
NO
NC
LG
FG
24V(+)
24V(-)