User Manual EM303B General Purpose Inverter 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 Metal Pipe IM 30cm MIN Signal Line Control Figure 3-9 Countermeasures Against Inductive Interference Device 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 Iron Case Metal Pipe Noise Filter EM303B Inverter IM 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 29 EM303B Inverter Cable Length ＜50m ＜100m ＞100m Carrier Frequency ＜10kHz ＜8kHz ＜5kHz F0-14 Function Parameter 10.000 5.000 2.000