Chint AC contactor NC8-65 220V

The Chint AC contactor NC8-65 220V is an electrical device commonly used in the field of power control. The following introduction will be unfolded from its basic information, working principle, application scenarios and other dimensions:  

 - Basic Information  

- Model Meaning  *Chint surface-mounted distribution box PZ30/8-way

- "NC8" represents the Chint NC8 series AC contactor;  

- "65" refers to the rated working current of the contactor under the AC-3/415V usage category, which is 65A;  

- "220V" indicates that the coil voltage of the contactor is 220V, meaning it needs to be connected to a 220V AC power supply to drive the electromagnetic system of the contactor.  

- Product Certifications  

- Complies with standards such as GB/T 14048.1, GB/T 14048.4, IEC/EN 60947-1, IEC/EN 60947-4-1, etc., and has obtained certifications such as CCC, UL, CE, KEMA, etc.  

- Enclosure Protection Class  

- IP20, which can prevent the intrusion of objects larger than 12.5mm, suitable for general industrial environments.  

 - Working Principle  

When a 220V AC voltage is applied across the coil, an alternating current is generated in the coil, thereby producing a magnetic field. Under the action of the magnetic field, the iron core generates electromagnetic suction force, attracting the armature to act, making the main contacts and auxiliary contacts of the contactor close or open, so as to realize the on-off control of the circuit. When the coil is powered off, the magnetic field disappears, the armature returns to the initial position under the action of the reset spring, the contacts are reset accordingly, and the circuit is disconnected.  

 - Structural Features  

- Compact Design  

- Small in size and compact in structure, which can save installation space and is convenient for installation and use in various electrical control cabinets.  

- Complete Accessories  

- Can be equipped with side-hung and top-hung auxiliary contacts, delay modules, mechanical interlock modules, surge suppressor modules, etc., to meet different control needs and application scenarios.  

- Technical Parameters  

- **Rated Insulation Voltage**: 690V.  

- **Rated Impulse Withstand Voltage**: 6kV.  

- **Conventional Free Air Heating Current**: The conventional free air heating current corresponding to 65A is usually about 80A.  

- **Rated Making Capacity**: The making current is 10×Ie (AC-3) or 12×Ie (AC-4). That is, for NC8-65, the rated making capacity is 650A under the AC-3 usage category and 780A under the AC-4 usage category.  

- **Rated Breaking Capacity**: The breaking current is 8×Ie (AC-3) or 10×Ie (AC-4). That is, the rated breaking capacity is 520A under the AC-3 usage category and 650A under the AC-4 usage category.  

- **Short-time Withstand Current**: It can withstand a short-time withstand current of 320A within 10s.  

- Application Scenarios  

 - Motor Control  

- Commonly used in circuits with AC 50Hz (or 60Hz) and rated working voltage up to 690V, it can frequently start and control AC motors. Combined with a suitable thermal overload relay to form an electromagnetic starter, it can protect the circuit from possible operational overload.  

- Industrial Automation Control  

- In various automated production lines, mechanical equipment and other fields in industrial production, it is used to control the start and stop, forward and reverse rotation, speed regulation, etc., of motors to realize the automatic control of the production process.  

- Power System  

- In power systems such as substations and switchgear rooms, it is used to control the on-off of power equipment, such as the switching control of transformers, capacitors, reactors, etc.  

The mechanical life and electrical life of Chint AC contactor NC8-65 220V are as follows:  

- **Mechanical Life**: The mechanical life of the whole series of products can reach 10 million times.  

- **Electrical Life**: Under the AC-3 415V usage category, the current non-derating electrical life can reach 1.2 million to 1.7 million times; under the AC-4 415V usage category, the current non-derating electrical life can reach 35,000 to 90,000 times.  

The working principle of Chint AC contactor NC8-65 220V is based on the synergistic effect of electromagnetic induction and mechanical action. It drives the action of the contact system through the magnetic field generated by the energized coil to realize the on-off control of the circuit. The specific principle is as follows:  

1、Core Working Principle**  

1. **Magnetic Field Generation by Coil Energization**  

When the coil of the contactor is connected to a 220V AC power supply, an alternating current is generated in the coil, thereby forming an alternating magnetic field. This magnetic field causes the iron core (static iron core) to generate electromagnetic suction force.  

2. **Armature Action Drives Contact Closure**  

The electromagnetic suction force overcomes the resistance of the reset spring and attracts the armature (movable iron core) to move toward the static iron core. The armature drives the main contacts and auxiliary contacts to act through the connecting rod:  

- **Main Contacts**: Close to connect the main circuit (such as the motor circuit), so that the load (such as the motor) is powered to work.  

- **Auxiliary Contacts**: According to the design, the normally open contacts close and the normally closed contacts open, which are used for signal feedback or interlock control of the control circuit.  

3. **Reset After Coil Power-off**  

When the coil is powered off, the alternating magnetic field disappears, the electromagnetic suction force disappears, and the reset spring pushes the armature back to the initial position. The contact system is reset accordingly:  

- The main contacts open to cut off the main circuit;  

- The auxiliary contacts return to the original state (normally open contacts open, normally closed contacts close).  

2、Roles of Key Components**  

3、Working Characteristics and Advantages**  

1. **AC/DC Compatibility**: The coil is powered by 220V AC, which is suitable for common industrial power supply environments, and the electromagnetic system design can adapt to the stable action of the alternating magnetic field.  

2. **Fast Response**: The time from coil energization to complete contact closure is usually within tens of milliseconds, meeting real-time control needs.  

3. **Mechanical and Electrical Life Guarantee**: Through the optimization of the electromagnetic system and contact materials (such as silver alloy contacts), wear and arc erosion are reduced, ensuring a long service life (mechanical life of 10 million times, and electrical life ranging from tens of thousands to millions of times depending on the usage category).  

*4、Combination with Application Scenarios**  

- **Motor Control**: Control the start and stop of the motor through the on-off of the contactor. When the coil is energized, the motor runs, and when powered off, it stops. The auxiliary contacts can be interlocked with the thermal relay to realize overload protection.  

- **Automation Circuits**: In PLC (Programmable Logic Controller) or relay control circuits, the contactor acts as an executive component. By controlling the on-off of the coil, it realizes the sequential start, interlock and other logic controls of multiple devices.  

*Summary**  

The working principle of Chint NC8-65 220V AC contactor can be summarized as "electricity generates magnetism, magnetism drives iron, and iron moves contacts". Through the coordination of the electromagnetic system and the mechanical system, it realizes the automatic control of the circuit. Its design takes into account reliability, service life and control flexibility, and is suitable for various scenarios in the field of industrial power transmission and automation.