Chapter 2 Installation and wiring
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(semiconductor fuse) must be used. Fast fuses type: gG protects only short circuit, gR protect
short circuit + overload.
(3) Electromagnetic contactor: (MC)
In order to ensure safety, the contactor allows the inverter to power on and off.
4) AC input reactor
Suppresses the higher harmonics to protect the inverter.
(5) Braking resistor
When braking the motor, the resistance can prevent the high voltage of the DC bus of the
inverter and improve the braking capability of the internal braking unit.
2.2.2 Measures for main circuit wiring
(1) When connecting circuits, follow the requirements of electrical brands and standards.
(2) Using the supply voltage at the output terminals (U, V, W) of the inverter leads to its
destruction.
(3) Use the insulated conductors and insulated protective tubes (if possible) to connect the
power supply and ground them.
(4) The inverter and the welding unit, high performance motor and the like cannot use a
common grounding cable.
(5) Earthing terminal E and earthing impedance are less than 10 ohms.
(6) Use the shortest earthing cable.
(7) Be careful not to create earthing loops when grounding multiple inverters.
8) Power cables and control cables must be separated, secure the distance of the power
cables from parallel control cables to more than 10 cm, or when the cables and control cables
are crossed. Parallel storage of power and control cables will cause interference.
(9) Normally, the distance between the inverters and the motors is less than 30 m, the current
generated by the parasitic capacitance can cause overshoot maximum current, incorrect
operation, inverter failure and equipment failure. The maximum distance is 100 meters. If the
distance is greater, put the reactor on the output side and lower the carrier frequency.
(10) Do not install an absorption capacitor or other capacitance resistive absorption devices!
(11) Make sure the terminals are fully tightened, the cables are well connected to the
terminals, are not loose, do not cause sparks and short circuit. To minimize interference in
1st environment, it is recommended (if not installed in a particular inverter type)
• Install the EMC category C1 filter on the input side of the inverter;
• Protect the interference of other devices by means of a choke or an RFI filter.
(12) Changing the direction of rotation of the electric motor shaft: the direction of rotation
can be changed by changing the two output lines at the output of the frequency converter
or at the terminal block of the electric motor.
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