Finder power relayWhat is the role of relays in industrial control systems? The relay can generate the minimum current for pull in action. What is the function of finder power relay in industrial control system?
As a control element, in general, the finder power relay has the following functions:
(1) Expand the scope of control. For example, when the control signal of multi contact relay reaches a certain value, multiple circuits can be switched, disconnected and connected at the same time according to different forms of contact groups.
(2) Zoom in. For example, sensitive relays and intermediate relays can control circuits with high power with a small control quantity.
(3) Integrated signal. For example, when a plurality of control signals are input to a multi winding relay in a prescribed form, the predetermined control effect is achieved by comparison and synthesis.
(4) Automatic, remote control and monitoring. For example, the relay on automatic equipment can form a program control circuit with other electrical appliances, so as to realize automatic operation.
In normal use, the given current must be slightly greater than the pull-in current before the relay can work stably. In general, the working voltage applied to the coil cannot exceed 1.5 times the rated working voltage, otherwise a large current will be generated and the coil will be burnt out.
Finder power relays are often used in household products, such as air conditioners, while g4a models are more common. In recent years, high-power household appliances have developed rapidly, such as electric water heaters, drinking fountains and so on.
In industry, three-phase high-power contactors can be used, which is relatively rare. Compared with the commonly used 3-5a contact capacity, there are also larger models, such as the difference between the capacity of 7a and 10A is not so obvious.
In use, the contact action process can be divided into contact closure and contact disconnection, that is, the process of relay pull-in and release, which is cycled and switched at a certain frequency to form the phenomenon of contact disconnection and closure. In the process of contact closing and opening, there will be many special physical and chemical phenomena, such as contact resistance, contact jitter and arc.