Mitsubishi Electric MR-D30 Instruction Manual page 61

3. SIGNALS AND WIRING
(2) Ferrite core
A ferrite core has the effect of reducing conduction noise in the band around 10 MHz and radiated noise
in the bands between 30 MHz to 100 MHz. When the shield effect of the shielded cable drawn out from
the cabinet is not obtained enough or when emission of conduction noise from a power supply line
should be suppressed, we recommend that you install the ferrite core.
Install the ferrite core at the position of the cable shown in the following figure. If the installation position
is incorrect, the ferrite core will not be effective.
Installing ferrite cores to the signal input wires and cables will suppress more noise. The following table
lists a ferrite core as an example.
ESD-SR-250 (NEC TOKIN), E04SRM563218 (SEIWA ELECTRIC) can also be used.
The effect of noise suppression rises as the number of passes though the ferrite core increases. Two or
more passes are recommended.
120 mm or less
Model
ZCAT3035-1330 (TDK)
Note. The values include wires (reference values) and are not guaranteed values.
One pass
3 - 12
Ferrite core
Impedance [Ω] (Note)
10 MHz to 100 MHz
80
Two passes
100 MHz to 500 MHz
150
Three passes