How does the three-phase ac motor identify the phase
Three-phase ac motor do not need to determine the phase, as long as want to need to correct, the height error phase sequence is reversed, as to A, B, C, C, A, B or C, A, B are the same, belong to the correct phase sequence, three-phase ac motor direction according to regulations, if the inversion of the exchange of two wires casually put correct phase sequence.
What you're talking about is the traditional start of the de-stress In fact, there is a soft start and frequency converter
The star delta launch is a time relay for three ac contacts String resistance and reactance start are now rare, and resistance is usually not in the distribution box The circuit of the auto-reducing voltage is a little bit closer to the star delta, but it is applied to the motor that is more than 90KW, and the auto-transformer is in or near the cabinet
