Step-down start

small motor spares suppliers of motor parts 

Specifications
1.20 years fan&motor manufactruer 
2.We can open mould&punch&diecast&finish&winding 

3.competitive price,high quality 
1, autotransformer (also called compensator) step-down start wiring: (1) high pressure side of the autotransformer into power grid, the low voltage side to the motor, there are several different voltage than tap to choose from. (2) features: set autotransformer change ratio of K, the original side voltage of U1, U2 = vice side voltage U1 / generator price K, vice edge current I2 (that is, through the line current of the motor stator winding) also according to the proportion is reduced, and because of I1 = I2 / K, the power supply of the motor starting current is directly 1 / K2 times when it generator is started. 1 / K times due to lower voltage, ac synchronous generator torque reduced to 1 / K2 times. Autotransformer vice edge from two to three groups of tap, such as secondary voltage of primary side voltage respectively 80%, 60%, 40%. Advantages: can auto spare parts be according to allow 3 phase induction motor the starting current and starting torque required for different tap to choose autotransformer achieve step-down start, use Y or Δ stator windings. Weakness: the equipment is big, the investment is more expensive. 


3 Phase induction Electrical Motor MS Series for winding machine

Specifications
ambient temperature:-15 -40 
above sea level : not exceed 1000m 

rated voltage:+-5%
2, star - triangle (Y - Δ) step-down start: (1) wiring startup of the stator into a star, first pick into Δ start over again. (2) the normal operation of the startup. Stator connect Δ alternator generator stator coil Y phase voltage U Δ = line voltage phase current UY = U1N = U Δ phase voltage U1N I Δ = line current IS current IY I Δ = = = IS IS (therefore diesel generator set starting current for direct use Δ connection starting current 1/3) due to the torque IS directly proportional to the square of water pump price the voltage, starting torque only Δ 1/3 connection IS started directly. Advantages: simple equipment, low price. Disadvantages: only when used in normal operation for Δ connection, buck than fixed, have can not meet the requirement of the launch. 3, yanbian triangle. Part which starts the motor stator windings into Y, another part of Δ form. Features: start, each phase winding of voltage, than connect. Full y connection, starting torque is bigger, but the winding structure is relatively complex, application restricted. 4, resistance (or reactance) step-down start. The capacity is not a lot of squirrel cage asynchronous motors can be used in tandem step-down at boot time for the stator circuit resistance (or reactor) to acmotor2.blogspot.com start the motor, to stay at the end of the motor starting resistance (or sub reactor), the resistance on the heat loss, with the reactor volume, the cost is large, this method is seldom used.