Wiring Attentions; Chapter Four Frequency Inverter Wiring - Veichi Electric AC60 series Manual

Chapter four Frequency Inverter Wiring

4.1 Wiring attentions

1. Wiring job can only be done by qualified professional personnel.
2. Before open the machine, make sure the power is safely cut off more than
10 minutes, otherwise there is a danger of shocking.
3.Absolutely prohibit the power input terminals to be connected to the
frequency inverter U, V or W output terminals；Absolutely prohibit short
circuit between the frequency inverter output terminals；Absolutely
prohibit the short circuit between the frequency inverter output
terminal and grounding terminal.
4. In order to minimize the impact of electromagnetic interference, when
the electromagnetic contactors and relays is very close to inverter,
you should consider the installation of surge absorption device.
5. When the peripheral equipment(filter 、 reactor)of inverter are
installed, the first step is use the 1,000 volts MΩ megger to measure
the grounding insulation resistance to ensure it not less than 4 MΩ.
6. Can not install
resistor-capacitor absorbing device in the frequency inverter U, V, W
output terminal because the frequency inverter' voltage output is PWM
pulse wave. If there is capacity which can improve power factor or
pressure-sensitive resistance which used for thunder-proof in the
voltage output side, the frequency inverter will break off or its parts
will be damaged, so it is necessary to dismantle them.
7. In order to reduce the leakage current of the earth, the motor cables
should be as short as possible. When the carrier frequency is less than
3KHz, the largest distance between frequency inverter and motor should
be less than 50 meters; When the carrier frequency is greater than 4KHz,
you should appropriately reduce this distance; In order to restrain
the progressive phase
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capacitance and