Dreieckbetrieb

Dreieckbetrieb, also known as delta connection, is a method of connecting the windings of a three-phase motor. In this configuration, the end of each winding is connected to the beginning of the next winding, forming a closed loop that resembles the Greek letter delta. This is in contrast to the star connection (or Y-connection), where one end of each winding is connected together at a common neutral point.

The primary effect of dreieckbetrieb is on the motor's voltage and current characteristics. When a motor is connected in dreieckbetrieb, the voltage across each winding is equal to the line voltage. However, the current flowing through each winding is less than the line current, specifically the line current is the square root of three times the winding current. This means that for a given line voltage, a motor connected in dreieckbetrieb will draw more current and produce more torque compared to a star connection.

Dreieckbetrieb is commonly used in applications where higher starting torque is required. It is often employed for larger motors or those that need to start under load. The ability to achieve higher torque at the start makes it suitable for machinery like compressors, pumps, and conveyors. However, the increased current draw also leads to higher power consumption. The choice between star and dreieckbetrieb often depends on the specific requirements of the application, balancing torque needs with energy efficiency and the motor's insulation capabilities.