10
LOADING AND INSTALLATION
10.3 Wiring
10.3.1 The precautions on the wiring
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EM
C AN
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LO
W
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E
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IVES
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LO
ADING A
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INST
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TION
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M
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NCE
AND
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TR
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ESH
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TIN
G
A
P
P
E
NDICE
S
INDE
X
POINT
1. Separate the ground of the surge absorber for lightening (E1) from that of the
PLC (E2).
2. Select a surge absorber for lightening whose power supply voltage does no
exceed the maximum allowable circuit voltage even at the time of maximum
power supply voltage elevation.
(2) Grounding
For grounding, perform the following:
• Use a dedicated grounding wire as far as possible. (Grounding resistance of
100 or less.)
• When a dedicated grounding cannot be performed, use (2) Common Grounding
shown below.
• For grounding a cable, use the cable of 2 mm
2
or more.
Position the ground-contact point as closely to the sequencer as possible, and
reduce the length of the grounding cable as much as possible.
Figure 10.23 Grounding procedures
(3) Joint grounding Not allowed
Grounding
PLC
Another
equipment
PLC
Another
equipment
PLC
Another
equipment
Grounding
(1) Independent grounding Best
(2) Common grounding Good
