The harmonic protector is a new type of protection device used to filter out high-order harmonics and protect precision instruments and equipment. It adopts ultra-microcrystalline alloy materials and innovative special circuits. It is mainly composed of voltage clamps, low-pass filters and absorbers.

The use of complete sets of electrical equipment in the power system​ can improve the reliability of the operation of electrical equipment in the system and reduce the probability of failure. In the electrical complete set, all kinds of electrical equipment including circuit breakers can be assembled in a cabinet according to the designed electrical main wiring to form a complete set of electrical devices.

The role of the low-voltage reactive power compensation device​ in the power supply system is to improve the power factor of the power grid, reduce the loss of the power supply transformer and transmission lines, improve the power supply efficiency, and improve the power supply environment.

The high-voltage variable frequency drive we usually call, the input power supply voltage is generally above 3kV, which is a high-power VFD. There are many types of VFDs, and the classification methods are not the same. The three basic classifications of high-voltage VFDs are listed below, with an introduction to each type of VFD.

There are many setting parameters for variable frequency drives, and each parameter has a certain selection range. In practical applications, it is not necessary to set and debug every parameter, and most of them only need to use the factory settings. Individual parameters need to be set and debugged according to the actual situation.

VFDs have relatively complete protection functions, and can realize various control and closed-loop regulation after cooperation with other intelligent equipment (PLC, DCS). In practical applications, avoiding risks and using them reasonably are the keys to improving the efficiency and service life of the inverter.

When choosing a soft starter, it is not only necessary to consider the load condition and load category, but also the continuity of the load (working system) and the start-stop frequency.

Whether the motor can start successfully is related to the capacity of the soft starter. This problem actually confuses the capacity of the soft starter with the capacity of the motor, or confuses the capacity with the driving torque, which are actually two different concepts. For the motor, the capacity and the driving torque are of the same nature.

1. External fault input protection. Instantaneous power-off terminals are used to add special protection devices, such as thermal relays, etc. 2. Loss of pressure protection. After the soft starter is powered off and the power is turned on again, no matter where the control terminal is, it will not start by itself, so as to avoid injury.

Soft start means that the voltage of the motor is gradually increased from zero to the rated voltage, so that the starting current of the motor during the starting process is changed from uncontrollable overload impulse current to controllable. And the size of the starting current can be adjusted as needed. There is no impact torque in the whole process of motor startup, but smooth startup and operation.