- 172 -
8.3.5 Leakage current and handling
There are two forms of leakage current when using the driver. One is leakage
current to the earth, and the other is leakage current between the cables.
1） Factors influencing the leakage current to the earth and the
solutions:
There are distributed capacitance between the lead cables and the
earth. The larger the distributed capacitance is, the larger the
leakage current will be. The distributed capacitance can be reduced
by effectively reducing the distance between the driver and the motor.
The higher the carrier frequency is, the larger the leakage current will
be. The leakage current can be reduced by reducing the carrier
frequency. However, reducing the carrier frequency may result in
addition of motor noise. Note that additional installation of reactor is
also an effective method to remove the leakage current.
The leakage current may increase following the addition of circuit
current. Therefore, when the motor power is high, the corresponding
leakage current will be high too.
2） Factors of producing leakage current between the cables and
solutions:
There is distributed capacitance between the output cables of the
driver. If the current passing the lines has higher harmonic, it may
cause resonance and thus result in leakage current. If thermal
relay is used, it may generate error action.
The solution is to reduce the carrier frequency or install output
reactor. It is recommended that thermal relay not be installed before
the motor when using the driver, and that electronic over current
protection function of the driver be used instead.
8.3.6 Precautions for Installing EMC input filter at the input end of power
supply
1） When installing the EMC input filter at the input end of the power
supply, it is recommended to use the EMC filter produced by
Shanghai Eagtop Electronic Technology Co., Ltd.
2） When using the filter, please follow its rated values
strictly. Since the filter belongs to Classification I electric appliances,
the metal enclosure of the filter shall be large and the metal ground
Note
!
To Next Page
Loading...
