Hioki ST5520-01 - Page 189

Appx.9
Inuence of Noise
It is efcient to take measures for conductive noise by monitoring with the HIOKI 3145 Noise
HiLogger. When the entry route is identied, taking the measures as shown in the gure below
is effective.
Instrument
Controller
(PC, PLC)
Motor Welder Inverter
Isolation
Common mode lter
in the entry route
Power line
L
N
PE
Different power line
L
N
PE
Isolation
Separating the power line
Figure. Measures for conductive noise
Separating the power line
It is desirable to prepare a different power line for the power system, welder, etc.
Inserting a common mode lter (EMI choke) in the entry route
Selecting and inserting several common mode lters with a high impedance level increases
effectiveness.
10
9
8
7
6
5
4
3
2
1
Appx. Ind.