Nameplate data of three-phase asynchronous motor

The nameplate data of a three-phase asynchronous motor includes the following items.
(1) Rated power PN: Mechanical power output on the shaft under rated operating conditions, kW.
(2) Rated voltage UN: The line voltage, V or kV, applied to the stator winding under rated operating conditions.
(3) Rated current IN: The line current of the stator winding when the motor outputs rated power at rated voltage, A.
The rated current can also be estimated using the following empirical formula:
In the formula, the unit of power is kW, and the unit of voltage is V.
(4) Rated speed nN: The speed of the motor at rated output power, rated voltage, and rated frequency, in r/min.
(5) Rated frequency fN: The standard frequency of the motor power supply voltage. The standard frequency of China's industrial power grid is 50 Hz.
The relationship between the rated output power on the shaft of a three-phase AC motor and the input power is:
In the formula: cos θ N is the power factor on the stator side of the motor under rated operating conditions; η N is the efficiency of the motor under rated operating conditions.
In addition, wound rotor asynchronous motors are also labeled with rotor rated potential and rotor rated current. The former refers to the potential (line potential) between the two collector rings when the rated voltage is applied to the specified sub winding and the rotor winding is open circuited; The latter refers to the line current of the rotor winding when the specified sub current is at the rated value.