Omron OMNUC W R88A-NCW152-DRT, Руководство пользователя

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6 DeviceNet Communications
6.3.2 Communications Line Noise Precautions
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6
„ Noise Precautions According To Wiring Methods
Noise precautions according to wiring methods are described below.
• To prevent inductive noise, do not wire the communications line, SYSMAC power lines
and power lines near each other. In particular, be sure to keep the power lines for invert-
ers, motors, regulators, and contactors at least 300 mm away from both the communica-
tions lines and the SYSMAC power lines. Also, provide separate conduits or ducts for
the communications lines and power lines.
• Do not install communications lines and SYSMAC power lines on the control panels on
which high-voltage devices are mounted.
• Because noise currents flow through metallic equipment (such as casings), the commu-
nications lines should be placed as far away from metallic equipment as possible.
• Ground the shield wire on the DeviceNet special cable at one point.
• If the same ground for the power line is used for the DeviceNet special cable and com-
munications power supply, there is a possibility that noise may be transmitted through
the ground line to the communications line. In order to avoid this, be sure that the power
line ground and the grounds for the DeviceNet special cables and the communications
power supply are located as far from each other as possible.
300 mm max.
300 mm max.
Power cable
Control cable
Low-voltage cable
DeviceNet special
cable
Communications line
SYSMAC I/O line
SYSMAC power line
General control circuit line
Power line
Ground (100
Ω
max.)
Suspended duct Floor duct
2
1
2 1
1 2 1: Communications line
SYSMAC I/O Line
2: Power line
Shielding