Mitsubishi Electric MELSEC-A series User Manual page 47

(2) Wiring to I/O device
(a) The solderless terminal with insulation sleeve is inapplicable to a
terminal block.
It is advisable to cover the wire connection part of a terminal with a
mark tube or insulation tube.
(b) Install wiring to a terminal block using the cable of core diameter 0.3 to
2
0.75mm
(c) Run the I/O line and output line away from each other.
(d) When the main circuit line and power line cannot be separated, use a
shielding cable and ground it on the programmable controller side.
However, ground it on the opposite side in some cases.
(e) When cables are run through pipes, securely ground the pipes.
(f) Run the 24VDC input line away from the 100VAC and 200 VAC lines.
(g) The cabling of 200m (656.2ft.) or longer distance may produce
leakage current depending on the capacity between lines and result in
an accident.
(h) As a countermeasure against the power surge due to lightning,
separate the AC wiring and DC wiring and connect a surge absorber
for lightning as shown in (i) of item (1).
Failure to do so increases the risk of I/O device failure due to lightning.
(3) Grounding
CAUTION
(a) Carry out the independent grounding if possible. (Grounding
resistance 100
(b) If the independent grounding is impossible, carry out the shared
grounding (2) as shown below.
Programmable
controller
Class 3
grounding
(1) Independent grounding.....Best
, and outside diameter 2.8mm or less.
PLC
Input
Output
DC
Be sure to ground the FG terminals and LG terminals to
the protective ground conductor. Not doing so could result
in electric shock or erroneous operation.
or less.)
Programmable
Other
controller
device
(2) Shared grounding.....Good
Shielded cable
Shield jacket
Programmable
Other
controller
device
Class 3
grounding
(3) Common grounding.....Not allowed
33
RA
Other
device