what is the power relay?
A power relay is a device that produces a transition in one or more electrical output circuits when the input or stimulus meets certain specified conditions. It can be used in neutral point direct grounding system as the directional component of zero-sequence current protection. Home appliances such as air conditioners often use power relays.
The action process of the contact can be divided into two parts of the contact closure and the contact opening. That is the relay's pull-in and release process. They are switched at a certain frequency to form a contact opening and closing phenomenon. In the process of contact closure and disconnection, there are many special physical and chemical phenomena, such as contact resistance, contact jitter and arcing.
When the movable contact and the static contact of the relay touch each other, the contact rebound will occur. That is the uncontrolled intermittent opening and closing. The Joule heat generated by the arc and the energized current at this time will greatly affect the relay. The ability to open and close.