How to choose the right Frequency converter (5 tips)

With the rapid development of the process of industrial automation, the Frequency converter as the frequency conversion debugging is also widely used. Frequency converter As an important role of variable frequency speed, energy saving, its main function is to control the power control device of the AC motor by changing the motor operating power frequency mode. Its advantage is not only for the company to improve the process production level, but also play an important role in energy savings. So how do you choose the right Frequency converter? Today Frequency converter manufacturers introduce Frequency converter purchase skills.

First of all, choose Frequency converter What are you started from?

The type of Frequency converter is selected according to the type of production machine, the speed range, static speed accuracy, and the starting torque requirements, the Frequency converter is the most appropriate. The so-called appropriate is both easy to use, and economically to meet the basic conditions and requirements of process and production.

How should I decide to choose Frequency converter?

1. Motors and Frequency converter they need to control

The number of motors. The general motor is extremely advisable at not more than 4 extreme, otherwise Frequency converter capacity is appropriately increased. Torque characteristics, critical torque, accelerated torque. In the case of the same motor power, the Frequency converter specification can be selected with respect to the high overload torque mode. Electromagnetic compatibility. In order to reduce the main power interference, the reactor can be added to the intermediate circuit or Frequency converter input circuit during use, or install the front isolation transformer. Generally, when the motor is more than 50m, the electric device, the filter, or the shield protection cable should be stringed in the middle of the motor and {[11].

2, Frequency converter Power selection

System efficiency is equal to Frequency converter Efficiency and motor efficiency product, only two are at higher efficiency, the system efficiency is higher. From the efficiency angle, pay attention to the following points when selecting Frequency converter power, pay attention to the following:

Frequency converter The power value is most appropriate at the time of the motor power value, and it is operated at a high efficiency value in the high efficiency value.

When the power classification of Frequency converter is not the same as the motor power classification, the power of Frequency converter is as possible to approach the power of the motor, but it should be greater than the power of the motor.

When the motor is frequently started, the brake work or the heavy-duty starting and more frequently, it can be selected to use Frequency converter long-term and safely.

Testing, the actual power of the motor is indeed surplus, and it can be considered Frequency converter that is less than motor power, but pay attention to whether the instantaneous peak current causes an overcurrent protection action.

When Frequency converter is not the same as the motor power, the setting of the energy-saving program must be adjusted to achieve a higher energy-saving effect.

3, Frequency converter Selection of the box structure

The box structure of Frequency converter should be adapted to the environmental conditions, that is, the temperature, humidity, dust, acid alkalinity, corrosive gases are mainly considered. Frequently with the following structural types are available for users:

Open-open IPOO types, suitable for screens, dishes, racks, especially multiple Frequency converter, especially multiple Frequency converter, in particular in electrical storage boxes, disc, especially multiple Frequency converter, but environmental conditions Higher; closed IP20 type is suitable for general use, can have a small amount of dust or a little temperature, humidity; the sealing IP45 is applicable to industrial field conditions; closed IP65 type applicable environmental conditions, water, dust and A certain case of corrosive gases.

4, Frequency converter capacity determined

Reasonable capacity selection itself is an energy saving and consumption measures. According to existing information and experience, there are three ways:

The actual power of the motor is determined. First, the actual power of the motor is first measured to select the capacity of Frequency converter.

Formula method. When a Frequency converter is used for multiple motors, it should be satisfied: at least consider the effect of an electric start current to avoid Frequency converter overcurrent trip.

Motor Rated Current Law Frequency converter. Frequency converter Capacity selection process, is actually a Frequency converter and the best matching process of the motor, the most common, safer is to make the Frequency converter capacity greater than or equal to the rated power of the motor. However, in the actual matching, consider the actual power of the motor and the rated power difference, usually the power of the device is large, and the actual needs is small, so the actual power of the motor is Frequency converter is reasonable, Avoid the Frequency converter of the selected Frequency converter to increase investment.

For light load, Frequency converter current should generally be selected according to 1.1n (n is the motor rated current), or press the largest motor of the output power rated value of Frequency converter by the manufacturer in the product. Power is selected.

5, main power

Power supply voltage and fluctuations. Special attention should be accomplished with Frequency converter low voltage protection settings, because in actual use, the power grid voltage is low.

Main power frequency fluctuations and harmonic interference. The interference in this regard will increase the thermal loss of the Frequency converter system, resulting in increased noise, and the output is lowered.

Frequency converter and the motor at work, the power consumption. When the system main power supply is designed, the power consumption factors of the two should be taken into account.