Omron NX701-1620, Руководство пользователя

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4 Installation and Wiring
NX-series CPU Unit Hardware User’s Manual (W535)
4-5 Co
ntro
l Panel In
stalla
tion
4
4-
5-6 Gro
unding
• Either install the Controller a minimum of 200 mm away from high-voltage lines or power lines, or
place the high-voltage lines or power lines in metal tubing and completely ground the metal tubing
to 100
Ω or less.
 Other Precautions
• Basic I/O Units have both plus and minus commons, so pay attention to the polarity when wiring.
This section describes the earthing methods and precautions.
Refer to 4-4-2 Grounding on page 4-35 for details on the grounding of the Controller.
Local potential fluctuations due to lightning or noise occurred by power devices will cause potential fluc-
tuations between ground terminals of devices. This potential fluctuation may result in device malfunc-
tion or damage. To prevent this, it is necessary to suppress the occurrence of a difference in electrical
potential between ground terminals of devices. You need to consider the earthing methods to achieve
this objective.
The recommended earthing methods for each usage condition are given in the following table.
4-5-6 Grounding
Considerations for Earthing Methods
Specification of communications cables
for EtherCAT and EtherNet/IP
Earthing methods
Equipoten-
tial bonding
system
Star earthing
Daisy chain
Connecting
devices and
noise sources
to separate
earth elec-
trodes
Connecting
devices and
noise sources
to a common
earth electrode
The cable shield connected to the connector
hood at both ends of the communications
cable
*1
*1. Use this cable when using EtherCAT or when using EtherNet/IP with 1000BASE-T.
Recom-
mended Recommended Not recom-
mended Not recom-
mended
The cable shield connected to the connector
hood at only one end of the communications
cable
*2
*2. You can use either of cables when not using EtherCAT or when using EtherNet/IP with 100BASE-TX or
10BASE-T.
Recom-
mended Recommended Not recom-
mended Not recom-
mended
Neither EtherCAT nor EtherNet/IP used Recom-
mended Recommended Not recom-
mended Not recom-
mended
Example: Separating Controller from Power Lines
Metal tubing
200 mm
200 mm
High-voltage power panel
Power lines
Power
lines
Ground to 100 Ω or less
Controller
Controller