8 -
10
EMC AND LOW VOLTAGE DIRECTIVES
8.
8.1.5
Ferrite core
Use of ferrite cores is effective in reducing conduction noise in the band of about 10MHz
and radiated noise of 30 to 100MHz.
It is recommended to attach ferrite cores when the shield of the shielded cable extracted
from the control panel does not work effectively, or when emission of the conduction noise
from the power supply line has to be suppressed.
We tested using ferrite cores from TDK Corporation, ZCAT3035-1330 and ZCAT2032-
0930, and RFC-H13 from KITAGAWA INDUSTRIES CO., LTD.
Make sure to attach a ferrite core to a cable at the position closest to the outlet of control
panel as possible. If attached at an improper position, the ferrite core will not work
effectively.
• Ferrite core
8.1.6
Noise filter (power supply line filter)
A noise filter is effective for suppressing conduction noise. It is not required to attach a
noise filter to the power supply line except for some models, however, attaching it can
suppress more noise. (The noise filter has the effect on reducing conduction noise of
10MHz or less. ) Use any of the following noise filters (double type filters) or equivalent.
The precautions required when installing a noise filter are described below.
(1) Do not bundle the wires on the input side and output side of the noise filter together.
When bundled, the output side noise will be induced into the input side wires from
which noise has been filtered out.
(2) Ground the noise filter ground terminal to the control panel with the shortest wire
possible (approx. 10cm).
Type
: ZCAT3035-1330, ZCAT2032-0930
Contact
: TDK Corporation
Type
: RFC-H13
Contact
: KITAGAWA INDUSTRIES CO., LTD
Model Name
FN343-3/01
FN660-6/06
ZHC2203-11
Manufacturer
SCHAFFNER
SCHAFFNER
TDK
Rated current
3A
6A
3A
Rated voltage
250V
(a) The noise is induced when the input and output
wires are bundled together.
(b) Separate the input wires from the output wires.