Switching capacitor AC contactor working principle

Switching capacitor contactors (hereinafter referred to as contactors) are special contactors for switching low-voltage shunt capacitors. They are widely used in reactive power compensation equipment with automatic compensation. They are suitable for electric power with AC frequency of 50hz and rated working voltage up to 380v. The system is switched on and off to 90kvar to improve the power factor. The contactor is of the building block type, the resistance circuit part is above the main circuit part, and the resistance circuit is three way. The main contacts are designed reasonably, with separate loads and reliable operation.

Switching capacitor contactor principle:

The premature contact of the series resistor is a resistance switching circuit. When the electromagnetic coil of the contactor is energized, the resistance switching circuit is turned on in advance, the current is charged to the capacitor through the resistor, the resistance suppresses the inrush current of the capacitor, and then the main contact is closed. Carrying capacitive current. After the resistor circuit completes the suppression of the capacitor closing current, it is automatically reset from the main circuit, which reduces the chance of burning the resistor when the capacitor is cut off.

Switching capacitor AC contactor works:

In order to save energy and electricity, in the power system, the effective power is increased to reduce the reactive power loss, so a power capacitor is added to the circuit to perform reactive power compensation. However, each time a group of power capacitors is put into the network, a current surge is applied to the circuit. Commonly known as "surge". The inrush current is generated by the capacitance of the power capacitor and the line impedance of the network, which is formed by oscillation in the line, and the peak value can reach 100 times of the rated current of the branch contactor. The compensation device works continuously for many years, and the action is frequent, and the failure rate is quite high, so measures have to be taken.

The series reactors in the line are bulky and costly, so now users are in urgent need of a capacitive contactor that is safe and reliable in accordance with international standards. At the same time, it is also hoped that the auxiliary contacts will be a little more, and the intermediate appliances in the line can be reduced.

CJX2A series switching capacitor contactor (hereinafter referred to as capacitor contactor or product) is small in size compared with similar domestic similar capacity products, novel structure and ingenious, easy to install, excellent performance, many auxiliary contacts, especially the charging suppression inrush device is unique Where it is domestically original. The main technical and economic indicators are higher than domestic similar products, safe and reliable in use, and in line with international standards, is the most ideal switching component in China.