Voltage relay is an electronic control device. It has a control system (also known as input loop) and a controlled system (also known as output loop). It is usually used in automatic control circuits. It is actually used. An "automatic switch" that uses a smaller current to control a larger current.
So it plays the roles of automatic adjustment, safety protection, and conversion circuit in the circuit. It is mainly used in relay protection devices of generators, transformers and transmission lines as the starting element for over-voltage protection or low-voltage blocking.
Low-voltage relay is an automatic control electrical appliance that operates according to a specific input signal. There are many types, including intermediate relays, thermal relays, time relays and other types.
Extended information:
As a control component, in summary, relays have the following functions:
1. Expand the control range: for example, multi-contact relays When the control signal reaches a certain value, multiple circuits can be switched, opened, or connected at the same time according to different forms of contact groups.
2. Amplification: For example, sensitive relays, intermediate relays, etc. can control circuits with very high power with a very small control amount.
3. Comprehensive signal: For example, when multiple control signals are input to a multi-winding relay in a prescribed form, the predetermined control effect is achieved after comparison and synthesis.
4. Automation, remote control, and monitoring: For example, relays on automatic devices, together with other electrical appliances, can form a program control circuit to achieve automated operation
Baidu Encyclopedia - Voltage Relay
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