Switching Technology of Contactors
Contactors are commonly used in a variety of switching circuits and are widely used in all kinds of electric machinery and lighting, heating and power equipment. It is characterized by a light weight, small size, free combination and other advantages. Below, lets look at the technology parameters of contactors in detail.
First, the famous technology parameters of contactor should include: rated current, rated voltage, allowable voltage drop and contact material.
1. Rated current (In): Indicates the rated current of the contactor, which can be related to the rated value of the contactor working power. The rated current of the contactor is marked on the product label, such as In=20A. Generally, the rated current is related to the contact material of the contactor, the maximum contact alternating and the maximum contact shaking current.
2. Rated voltage (Ue): It is related to the maximum voltage allowed for contactor control work. Generally, it should match the rated voltage of the circuit, such as 220V or 380V.
3. Allowable voltage drop: Indicates the allowable voltage drop between the main contacts of the contactor under the rated current In. Generally, the allowable voltage drop should match the rated power of the circuit, such as 0.25 to 0.4 of the rated circuit voltage.
4. Contact material: refers to the composition of the contact material, which should be related to the voltage, current and other parameters of the contactor. Generally, contact material can be divided into silver alloy (for AC power supply), gold alloy (for DC power supply), tungsten molybdenum alloy, and graphite material under special circumstances.
Contactors and circuit breakers, the two main connection and disconnection elements in the circuit, are used in similar switching circuits and have similar structures. The biggest difference is that contactors are used in circuits with higher power, while circuit breakers can protect circuits with low power but also have lower voltage drop and contact life than contactors.
In short, contactors are a type of switch and are widely used, so it is very important to understand the technology parameters of the contactor and apply them correctly, so as to improve the efficiency, stability and safety of the circuit.
