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What is a two-position relay and how does it work?

The two-position relay, as its name implies, means that the relay has two positions and can be self-holding in both positions at the same time. In fact, a two-position relay is a magnetic holding relay with two coils.

After coil A is energized, the relay contacts are activated, even if it is de-energized, the contacts do not return; after coil B is energized, the relay contacts are returned. In other words, if the position of the two-position relay contact is reversed, one coil must be charged.

Two-position relays are more common in the secondary circuit of substations, and they are mostly used in circuits that require high status and reliability. Such as the voltage switching circuit and voltage parallel circuit of the double-bus wiring.

working environment

1. Atmospheric pressure: 80 ~ 110kPa;

2. The relative humidity of the air is not more than 90% (25 ° C);

3. Surrounding medium temperature: -25 ~ + 40 ℃;

4. The installation position is not more than 5 ° from any direction of its installation vertical plane;

5. Strong vibration and shock are not allowed at the place of use;

6. The place of use shall be free of explosive medium, and the surrounding medium shall not contain corrosive metals, gases and conductive media that damage insulation, and shall not be filled with water vapor and severe mold;

7. The place of use shall have facilities to prevent rain, snow, wind and sand;

8, the place of use is not allowed to have a strong external magnetic induction.