Omron NX Series Hardware User Manual page 168

5 Installation and Wiring
When you connect a computer or other peripheral device to a Controller that has a
non-isolated DC power supply, either ground the 0-V side of the external power supply
for the Unit power supply or do not ground it at all.
If the peripheral devices are grounded incorrectly, the external power supply for the
Unit power supply may be short-circuited. Never ground the 24-V side of the power
supply, as shown in the following figure.
Unit power
supply
terminals
External power supply (Unit power supply)
Units with Ground Terminals and Type of Ground Terminals
Functional Grounding
CPU Unit,
NX Unit
l Units with Ground Terminals
• CPU Unit
• Additional NX Unit Power Supply Unit
• Shield Connection Unit
5-38
CAUTION
Non-isolated type Communications Interface Unit, etc.
CPU Unit
Non-isolated DC
power supply
Internal
power supply
circuit
(No-isola-
tion)
External device
(e.g. computer)
Cable
NX-series NX502 CPU Unit Hardware User's Manual (W629)