EM15 User’s Manual
3. Installation of Frequency Inverter
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3.9 Cautions for Main Circuit Wiring
3.9.1 Power Supply Wiring
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It is forbidden to connect the power cable to the inverter output terminals, otherwise, the internal components
of the inverter will be damaged.
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To facilitate the input side over current protection and power off maintenance, the inverter shall connect to the
power supply through the circuit breaker or leakage circuit breaker and contactor.
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Please confirm that the power supply phases, rated voltage are consistent with that of the nameplate, otherwise,
the inverter may be damaged.
3.9.2 Motor Wiring
If the cable between the inverter and the motor is too long, the higher harmonic leakage current of the output
will produce by cable length, which will lead to adverse impact on the inverter and the peripheral devices. It is
suggested that when the motor cable is longer than 100m, add AC reactor at output side. Refer to the following
table for the cable length and carrier frequency setting.
Length of cable between the inverter and motor
Carrier frequency (d6-00)
Less than 50m
Less than 15kHz
Less than 100 m
Less than 10kHz
More than 100m
Less than 5kHz
3.9.3 Grounding Wiring
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The inverter will produce leakage current. The higher the carrier frequency is, the larger the leakage current
will be. The leakage current of the inverter is more than 3.5mA, and the exact value of the leakage current is
determined by the using conditions. To ensure the safety, the inverter and the motor must be reliably grounded.
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The grounding resistance shall be less than 10ohm. For the grounding wire diameter requirement as IEC
standard.
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Do not share grounding wire with the welding machine and other power equipment.
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In the applications with more than 2 inverters, keep the grounding wire out from forming a loop.
Diagram 3-8 Grounding Wire Connection Sketch Map
3.9.4 Soluction for Conduction and Radiation Interference
Diagram 3-9 Connection of conduction and radiation interference solutions
