Mitsubishi MELSEC-A A1SCPUC24-R2, Руководство пользователя

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11
(2) Connection of power and earth wires
Earthing and power supply wires for the programmable controller
system must be connected as described below.
(a) Provide an earthing point near the power supply module. Earth
the power supply's LG and FG terminals (LG : Line Ground, FG
: Frame Ground) with the thickest and shortest wire possible.
(The wire length must be 30 cm (11.18 in.) or shorter.) The LG
and FG terminals function is to pass the noise generated in the
programmable controller system to the ground, so an
impedance that is as low as possible must be ensured. In
addition, make sure to wire the ground cable short as the wires
are used to relieve the noise, the wire itself carries large noise
content and thus short wiring means that the wire is prevented
from acting as an antenna.
(b) The earth wire led from the earthing point must be twisted with
the power supply wires. By twisting with the earthing wire,
noise flowing from the power supply wires can be relieved to
the earthing. However, if a filter is installed on the power
supply wires, the wires and the earthing wire may not need to
be twisted.