GK600E User Manual
Chapter 3 Installation and Wiring
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3.11.3 Leakage Current Suppression
Leakage current passes through the line-to-line and ground distributed capacitors at input &
output sides of drive, and its size is associated w ith the capacitance of distributed capacitor and
the sw itching frequency. Leakage current is classified into ground leakage current and
line-to-line leakage current.
Ground leakage current not only circulates inside drive system, but may also influence other
equipment via ground loop. Such a leakage current may result in malfunction of RCD and other
equipment. The higher the sw itching frequency of drive is, the bigger the ground leakage current
w ill be. The longer the motor cables and the bigger the parasitic capacitance are, the bigger the
ground leakage current w ill be. Therefore, the most immediate and effective method for
suppression of ground leakage current is to reduce the sw itching frequency and minimize the
length of motor cables.
The higher harmonics of line-to-line leakage current that passes through betw een cables at output
side of drive w ill accelerate the aging of cables and may bring about malfunction of other
equipment. The higher the sw itching frequency of drive is, the bigger the line-to-line leakage
current w ill be. The longer the motor cables and the bigger the parasitic capacitance are, the
bigger the line-to-line leakage current w ill be. Therefore, the most immediate and effective method
for suppression of ground leakage current is to reduce the sw itching frequency and minimize the
length of motor cable. Line-to-line leakage current can also be effectively suppressed by mounting
additional output reactors.
3.11.4 Use of Power Supply Filter
Since AC drives may generate strong interference and are also sensitive to outside
interference, pow er supply filters are recommended. Pay close attention to the follow ing
instructions during the use:
Enclosure of the filter needs to be reliably grounded;
Input lines of the filter shall be kept as far aw ay from output lines as possible so as to avoid
mutual coupling;
Filter shall be as close to the drive side as possible;
Filter and drive must be connected to the same common ground.
