The three major attributes of the AC contactor

First, the three major attributes of the AC contactor:

1. The AC contactor coil.Cils are usually identified by A1 and A2 and can be simply divided into AC contactors and DC contactors. We often use AC contactors, of which 220 / 380V is the most commonly used:

2. Main contact point of the AC contactor.L1-L2-L3 is connected to the three-phase power inlet line, and T1 T2-T3 is connected to the power outlet line, and can be used to connect the load line.The main contacts of the AC contactor are often open contacts, mainly connected to the main circuit, to control the start and stop of the motor and other equipment!

3. Auxiliary contacts of the AC contactor.The auxiliary contacts can be divided into constant open point NO and normally closed point NC.

3-1 Often open point NO, usually often open point NO is mainly used for contactor self-locking control and transfer operation signal to use, such as: AC contactor often open point NO to a red indicator light can serve as the motor operation indicator light, when the AC contactor has electricity, often open point NO closed, turn on the indicator light, to transmit the motor or circuit operation signal.

3-2, Normal closed point NC of the AC contactor.Generally, the NC is used for interlocking and signal transmission.

For example, the motor positive and reverse control circuit uses the interlocking function of the contactor constant closed point NC.

For example, the AC contactor constant closing point NC is connected to a green indicator light, which can serve as a stop indicator of the circuit or motor. When the AC contactor is powered, the constant closing point NC is disconnected, the stop indicator light is off, the corresponding operation indicator light is on, and the circuit runs.

Second, I understand the three external attributes of the AC contactor, and then take a simple look at the inside of the AC contactor:

1. The main components of the AC contactor: coil, iron core, reset spring, contact system and armature and other components.

1. Simply understand the armature of the AC contactor.Armature connects the contact system, when the armature moves up and down, the contact will change accordingly, such as: often open point NO closed, often closed point NC disconnected and so on, this is the basic usage!

2. Other important components: core, coil, and reset springs!A brief understanding of this article is:

Here’s how AC contactors work in the most accessible language:

Before the AC contactor is not electrified: the coil can not be electric, the core has no electromagnetic suction, the armature will not move, the spring elasticity remains normal, this time often open point NO is off, often closed point NC is on, this is the normal state.

AC contactor electric: coil electric, iron core electromagnetic suction, can overcome the reset spring elasticity, pull the bit move down, this time, the contact system will change: often open point NO closed, often closed point NC disconnected, this is the most basic contactor control, contactor is by contact change to indirectly control the circuit!

After the AC contactor loses power or power off, the coil shall not be electric, the core has no electromagnetic suction, at this time, the elasticity of the reset spring drives the armature reset, the armature bounce, at this time, the armature drives the contact system of the AC contactor to move, restore to the initial state: the often open point NO disconnected, the often closed point NC closed on.


Post time: Mar-09-2022