User Manual
EM303B General Purpose Inverter
29
Countermeasures Against Inductive Interference
As stated previously, except installing a noise filter, all output cables can be routed through a
grounded metal pipe to prevent inductive interference on the output side. The distance
between output cables and signal line should
>
30cm, and the inductive interference will be
reduced considerably, as shown in Figure 3-9.
MCCB
Signal Line
30cm MIN
Metal Pipe
IM
Control
Device
EM303B
Inverter
Figure 3-9 Countermeasures Against Inductive Interference
Countermeasures Against Radio Frequency Interference (RFI)
RFI will be generated from the inverter as well as the input cable and the output cable. Install
noise filters on both input and output sides, and shield inverter with an iron case to reduce
RFI. As shown in Figure 3-10.
MCCB
Noise
Filter
EM303B
Inverter
IM
Iron Case
Metal Pipe
Noise
Filter
Figure 3-10 Countermeasures Against RFI
Cable Length Between Inverter and Motor
The longer cable between the inverter and motor is, the higher carrier frequency is, and the
greater high-frequency harmonic leakage current on its cable is. All of which will affect
inverter and its peripherals. See Table 3-2 to adjust carrier frequency for reducing the
high-frequency harmonic leakage current.
When motor cable
>
50m, please connect a special 3-phase AC reactor of the same capacity
as that of the inverter to the output terminals.
Table 3-2 Cable Length and Carrier Frequency Between Inverter and Motor
Cable Length
<
50m
<
100m
>
100m
Carrier Frequency
<
10kHz
<
8kHz
<
5kHz
F0-14 Function Parameter
10.000
5.000
2.000