Hello, welcome to Sherry’s Fun Fan Classroom.In this video, we will share the principle and wiring method of the three-phase AC fan:

The three-phase AC fan uses a three-phase asynchronous motor inside, because the phase difference between any two phases of the three-phase power is 120°, so only the three-phase power is connected to the three-phase winding of the stator to form a rotating magnetic field. drive the rotor to rotate. There are two connection methods for three-phase windings, which are star connection and delta connection, so what is the difference between the two connection methods?

The star connection method is to connect one end of each phase winding to one point (U2, V2, W2), and their other ends (U1, V1, W1) are used as lead wires, respectively connected to the three phase lines of the three-phase power supply, which looks like a star.

The delta connection is to connect the three-phase windings end to end (U2-V1, V2-W1, W2-U1), and then lead out three wires at the connection point to connect to the three-phase power supply, which looks like a triangle.

It can be seen that under the star connection, the load line voltage = the power line voltage, the load phase voltage = the power supply phase voltage, and the line current = the phase current; while under the delta connection, the load phase voltage = the power line voltage, and the line current = √3times the phase current. Therefore, the delta connection can provide greater electromagnetic torque, thereby reducing the slip rate and increasing the speed. For the same type of fan, the delta connection will make the fan have greater air volume and higher back pressure.

Fans that support two wiring methods will generally lead out all six wires of the three-phase winding for users to choose how to wire, while some fans will be connected internally, so only three wires are connected to the three phases of the power supply. When wiring, the user should pay attention to the nameplate parameters and wiring diagram of the fan, and choose the appropriate voltage range and wiring method. If you are not sure, you can contact us. We have a professional technical team to provide you with high-quality after-sales service!