Omron OMNUC 88D-UP20HA, Руководство пользователя

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2-38
•
No-fuse breakers (MCCB), surge absorbers, and noise filters (NF) should be positioned near the input
terminal block (ground plate), and I/O lines should be isolated and wired using the shortest means
possible.
•
Wire the noise filter as shown at the left in the following illustration. The noise filter should be installed
at the entrance to the control panel whenever possible.
1
2
3
4
NF
E
1
2
3
4
NF
E
Good: Separate input and output
AC input
Ground
AC output
NO: Noise not filtered effectively
AC input
Ground
AC output
•
Use twisted-pair cables for the power supply cables whenever possible, or bind the cables.
Driver
Binding
L1
L2
or
Driver
L1
L2
•
Separate power supply cables and signal cables when wiring.
H
Control Panel Structure
Any gaps in the cable entrances, mounting screws, cover, or other parts of a control panel can allow
electric waves to leak from or enter the control panel. The items described in this section must be abided
by in panel design and selection to ensure that electric waves cannot leak or enter the control panel.
D
Case Structure
•
Use a metal control panel with welded joints on the top, bottom, and all sides. The case must be electri-
cally conductive.
•
When assembling the control panel, remove the coating from all joints (or mask the joints when coat-
ing) to ensure electrical conductivity.
•
Be sure that no gaps are created when installing the control panel, as gaps can be caused by distortion
when tightening screws.
•
Be sure there are not any electrically conductive parts that are not in electrical contact.
•
Ground all Units mounted in the control panel to the panel case.
D
Cover Structure
•
Use a metal cover.
•
Use a water-proof structure, as shown in the following diagram, and be sure there are no gaps.
•
Use electrically conductive packing between the cover and the case, as shown in the following dia-
gram. (Remove the coating the contact points of the packing (or mask the contact points when coat-
ing) to ensure electrical conductivity.)
System Design and Installation
Chapter 2