Power Supply Module; Others - Mitsubishi MELSEC- Q Q12PHCPU User Manual

8 EMC AND LOW VOLTAGE DIRECTIVE

8.1.4 Power supply module

8.1.5 Others

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Always ground the LG and FG terminals after short-circuiting them.
(1) Ferrite core
A ferrite core has the effect of reducing radiated noise in the 30MHz to 100MHz
band.
It is not required to fit ferrite cores to cables, but it is recommended to fit ferrite
cores if shield cables pulled out of the enclosure do not provide sufficient
shielding effects.
It should be noted that the ferrite cores should be fitted to the cables in the
position immediately before they are pulled out of the enclosure. If the fitting
position is improper, the ferrite will not produce any effect.
In the CC-Link system, however, ferrite cores cannot be fitted to cables.
(2) Noise filter (power supply line filter)
A noise filter is a component which has an effect on conducted noise.
It is not required to fit the noise filter to the power supply line, but fitting it can
further suppress noise.
(The noise filter has the effect of reducing conducted noise of 10 MHz or less.)
The precautions required when installing a noise filter are described below.
(a) Do not bundle the wires on the input side and output side of the noise filter.
When bundled, the output side noise will be induced into the input side wires
from which the noise was filtered.
Filter
1) The noise will be included when the
input and output wires are bundled.
(b) Earth the noise filter earthing terminal to the control cabinet with the shortest
wire possible (approx. 10 cm (3.94 inch)).
Reference
Noise Filter
Model Name
Manufacturer
Rated current
Rated voltage
Input side Input side
(power supply side) (power supply side)
Introduction
Output side
(device side)
FN343-3/01
SCHAFFNER
3 A
MELSEC-Q
Filter
2) Separate and lay the input
and output wires.
FN660-6/06 ZHC2203-11
SCHAFFNER
6 A
250 V
Output side
(device side)
TDK
3 A
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