Precautions for the surrounding environment of the inverter

The peripheral components of the inverter mainly include cables, contactors, air-openers, reactors, filters, and braking resistors. Whether the selection of the peripheral components of the inverter is correct or appropriate also directly affects the normal use of the inverter and the service life of the inverter. Therefore, after selecting the inverter, we must also correctly select its peripheral components. Below we will briefly explain the precautions for the selection of peripheral equipment.
1
Line breaker setting and selection
In order to protect the primary wiring on the power supply side of the inverter, install a wiring breaker. The choice of circuit breaker depends on the power factor on the power supply side (varies with supply voltage, output frequency, load). The operating characteristics are affected by the high-frequency current, and it is necessary to select a large capacity.
2
Line contactor
The inverter can be used without a line contactor. The line contactor can be stopped, but the brake function of the inverter will not be used.
3
Motor side contactor
If a contactor is provided between the inverter and the motor, it is in principle not allowed to switch during operation. When the inverter is connected during operation, there will be a large inrush current, so the inverter overcurrent protection action. When setting the contactor for switching to the grid, be sure to switch after the inverter stops output and use the speed search function as appropriate.
4
Thermal relay setting
In order to prevent the motor from overheating, the inverter has electronic thermal protection. However, when one inverter drives multiple motors and multi-stage motors, set a thermal relay between the inverter and the motor. The thermal relay is set to 1 times the motor nameplate at 50 Hz and 1.1 times at 60 Hz.
5
Power factor improvement
To improve the power factor, you can insert an AC reactor into the inverter’s incoming line or add a DC reactor to the DC loop. When the inverter output side is connected to the capacitor filter for improving the power factor, there is a danger of damage and overheating due to the high-frequency current output from the inverter. In addition, the inverter will overcurrent and cause current protection. Please do not connect the capacitor filter.
6
About radio interference
There is a high-frequency component in the output (main circuit) of the inverter, which can cause interference to communication devices (such as AM radios) used near the inverter. Filters can be installed to reduce interference. In addition, it is also effective to ground the inverter and the motor and the power supply wiring on the metal pipe.
7
Power cable wire diameter and wiring distance
When the wiring distance between the inverter and the motor is long (especially at low frequency output), the motor torque will drop due to the cable voltage drop; use a sufficiently thick cable wiring; when the operator is installed elsewhere, use a dedicated connection. Cable; when operating remotely, the distance between analog, control line and inverter should be controlled within 50 meters; the control signal should be properly shielded from ground.

发表评论

电子邮件地址不会被公开。 必填项已用*标注

Need help? Email Us Here! Chat With Us Now!

← Prev Step

Thanks for contacting us. We'll get back to you as soon as we can.

Please provide a valid name, email, and question.

Powered by LivelyChat
Powered by LivelyChat Delete History