Reactive Power Compensation Switching Contactor

The CJ19C Reactive Power Compensation Switching Contactor (single-phase series) is a dedicated device engineered for the crucial task of switching low-voltage single-phase capacitors or for providing individual phase compensation in three-phase systems. It is extensively utilized within automatic compensation equipment for reactive power management. This precise product is designed for 50Hz AC electrical systems with a rated operational voltage up to 220V, capably handling capacitive switching duties for loads up to 90kvar to achieve targeted power factor correction. This single-phase capacitor switching contactor represents an enhanced design from our factory, developed as an improvement upon the original CJ19C (16C) platform. For guaranteed performance and longevity, the Reactive Power Compensation Switching Contactor must be applied in accordance with these standard working and installation conditions: a) The surrounding air temperature should be maintained between -5°C and +40°C, with the average temperature over any 24-hour period not exceeding +35°C. b) The installation site's altitude is limited to a maximum of 2000 meters above sea level. c) Humidity specifications require that the relative air humidity at the installation point does not exceed 50% when the temperature is +40°C. Additionally, the average minimum temperature of the wettest month of the year must not be higher than +25°C, and the corresponding average maximum relative humidity for that month must stay below 90%. d) The device is rated for environments with a pollution degree of 3. e) Its installation category is classified as III. f) Mounting must occur in a location that is free from significant shaking, mechanical impact, or vibration. g) The contactor should be installed such that its mounting surface is inclined no more than 5 degrees from the vertical plane.

The operational sequence that defines the product is detailed in Figure 1. The diagram above the dotted line illustrates the control circuit for capacitor switching, while the area below depicts the connected single-phase capacitor bank. Integral to its design is the resistor switching circuit, formed by early-make contacts wired in series with current-limiting resistors. When the electromagnetic coil receives power, this resistor circuit is the first to close. This allows the initial surge of current to be safely channeled through the resistors to charge the capacitors, thereby effectively suppressing the potentially damaging inrush current. Only after this controlled pre-charge phase do the main contacts close, assuming the full capacitive load for normal operation. An essential protective feature of this Reactive Power Compensation Switching Contactor is the automatic disconnection and reset of the resistor circuit once its inrush suppression role is fulfilled. This design drastically minimizes the risk of resistor failure during the capacitor disconnection event, ensuring higher system reliability, reduced maintenance intervals, and enhanced operational safety for your reactive power compensation infrastructure.

CJ19C Single-Phase and Three-Phase Y-Type (requires three contactors) Wiring diagram is shown in Figure 2.

The CJ19C (Single-Phase)-32 contactor has two auxiliary contacts, with three combinations.

Auxiliary contact combinations are shown in Table 1. Auxiliary modules can be installed on both sides of the contactor to increase the number of auxiliary contacts.

 

Two types of auxiliary contacts are available:

LA8-DN11 (one normally open and one normally closed)

LA8-DN20 (two normally open); selected by the user when ordering.

External Dimensions and Installation Dimensions

The CJ19C (single-phase)-32 contactor can be installed using M4 screws and lock washers, or using a 35mm mounting rail.

See Figure 3 for the external dimensions and installation dimensions of the CJ19C (single-phase)-32 contactor.