A three-way switch or changeover switch is a type of switch that can transfer a certain amount of electrical load at a certain current level between two power sources. Usually, this happens somewhere between the generator and the city electricity during a power outage.
Technical specifications of the changer key
Three-way electric switch of Shahr Generator, which is one of the industrial electrical equipment and can be considered as a combination of two single switches that are connected to each other by an interlock mechanism. During the design of changeover panels, instead of mechanical or electrical interlocking of two contactors, the changeover switch can be used as an alternative to perform the changeover operation. The changer key supports three modes, which we have described below.
- Connecting to the primary power supply: Usually, the primary source in these keys is city electricity.
- Connecting to the secondary power supply: Usually, the secondary source in these keys is a generator.
- mode off: In this case, the load is not connected to any source.
As mentioned, changeover switches are used in two-bridge, three-bridge and four-bridge levels and in the following systems:
First mode: as two bridges in single-phase systems with neutral or two-wire systems
Second mode: as three bridges in three-phase systems without neutral or three-wire systems
Third mode: in the form of four bridges in three-phase systems with neutral or four-wire systems