As a Power Relay Supplier, share with you.
Power relay is a device that can generate a jump in the output circuit of one or more electrical appliances when the input quantity (or excitation quantity) meets certain prescribed conditions, and can be used in a direct neutral grounding system. Directional element for zero sequence current protection. It has a wide range of applications. Today we will talk about the application advantages of Power Relay.
Applications in home appliances such as air conditioners often use power relays. In recent years, high-power home appliances have developed rapidly, such as electric water heaters, water dispensers, etc., all use this type of relay.
As the three-phase high-power contactors are available in the industry, it is relatively rare. Compared with the commonly used contact capacity of 3-5A, there are also larger models such as the capacity of 7A, and the difference between 10A is not so obvious.
In use, its contact action process can be divided into two parts: contact closing and contact opening, that is, the pull-in and release processes of the relay. They cycle to form a contact opening and closing phenomenon at a certain frequency. In the process of contact closure and opening, there are many special physical and chemical phenomena, such as contact resistance, contact jitter and arc.
Working principle of power relay:
1. Principle of action when contacts are closed
When the moving contact and the static contact of the relay are in contact with each other, the contact bounces, that is, the uncontrolled gap opening and closing. The Joule heat generated by the arc and the current at this time greatly affects the relay. Opening and closing ability.
2. Principle of action when contacts are open
When the contact is disconnected to cut off the load, dazzling sparks and arcs will be generated. The generated arc should continue until the arc voltage drops below the minimum arc voltage value, which will cause greater damage to the contact. Different contact materials and contact gap sizes directly affect the emission state of the arc electrons and the difficulty of occurrence, so they are important conditions for determining the arc.
The above is the entire content of the power relay. When selecting, you should also carefully confirm the data sheet. Each relay has its own index, and the relay is selected according to the design circuit requirements.
What are the conditions for selecting relays?
1. Understand the necessary conditions first
1) The power supply voltage of the control circuit, the maximum current that can be provided;
2) the voltage and current in the controlled circuit;
3) What groups of contacts are needed for the controlled circuit.
Our company also has 19F Relay on sale, welcome to consult.