For Delta connection, the supply voltage must be same as the rated motor voltage.It required Six leads or terminals Motor (Delta Connected).Starting Torque is also reduce to one-third because starter reduce the starting current to one-third of the rated current.Two Speeds One Direction Three Phase Motor Connection Power and Control Diagrams.Three Phase Motor Connection Reverse and Forward Power and Control wiring diagrams.It reduced the starting current to one-third (approximately) as compared to DOL (Direct ON Line Starter).
#STAR DELTA PROBLEM PDF INSTALL#
Why We Need to Install a Starter with a Motor?.
#STAR DELTA PROBLEM PDF FULL#
Since the motor is connected in Delta now, therefore, each phase of the motor will receive full line voltage (400V) and the motor will start to run in full motion.In addition, Contact 2 (which is in the line C3) will open, by which, there would not be any chance of activation of coil 3 (C3) Therefore, the motor winding will be connected in Delta. Similarly, When C3 off, then star connection of winding will also open. Contactor 3 (C3) will be off, because of which the open link of C3 will be close (which is in the line of C2) thus C2 will also energize.For the specific time (generally 5-10 seconds) in which the motor will be connected in star, after that the Timer contact (Ia) will be open (We may change by rotating the timer knob to adjust the time again) and as a result.
The close contact of C3 in the Delta line opens because of which there would be no chance of activation of contactor 2 (C2).Since winding is connected in Star, hence each phase will get √3 times less than the line voltage i.e. Thus C1 Contactor is also energized and Three Phase Supply will reach to the motor. When C3 is energized, its auxiliary open links will be closed and vice versa (i.e.