In motor starters, this is usually done using contactors. Explanation of this can easily be done using a circuit diagram.
There are three contactors, the main, star and delta contactors-all these contactors can be the same type. There are many ways of wiring a star delta but here I will only give a generalized answer.
First, the main contactor and star contactors are energised thus the motor runs in star. After about 5 seconds, the timer which gets energized at the same time as the main and star contactors, switches its CONTACTS i.e the normally open closes and the normally close opens. This dienergize the star contactor and energized the delta contactor. Thus, the motor now runs in delta.
A star-delta motor should be supplied star-delta.Wye is simply another name for star. Star-delta motors use a star or wye configuration to start, and a delta configuration to run. This reduces the voltage on the windings during the high current starting time.
The Star-Delta control circuit diagram shows the delta contact and the main contact.
when starting a 3 phase induction motor,first start with star connection,because reduced current is being applied and after start change it to delta connection then. full line current is applied to the motor.
Star voltage is 1 / 1.732, or 0.577 delta voltage. (1.732 is the square root of 3.) It follows, then, that star current is 0.577 delta current.Not asked, but answered for completeness, star power is 0.5772, or 0.3333 delta power. This is why large motors use a star-delta start sequence - to minimize startup thermal stress.
No difference. Y is used as a symbol to indicate the star connection.
In manual star delta starter, the change over from star to delta does not happen automatically. The operator or user puts on the starter, and after few seconds he pushes a lever or handle to change over to Delta. In automatic method, change over happens from star to delta using an automatic preset timer.
In manual star delta starter, the change over from star to delta does not happen automatically. The operator or user puts on the starter, and after few seconds he pushes a lever or handle to change over to Delta. In automatic method, change over happens from star to delta using an automatic preset timer.
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The Delta Star was created in 1983.
hahahaa
The change from star to delta in the startup of an electrical motor involves switching the motor windings from a configuration where they are connected in a star pattern to a configuration where they are connected in a delta pattern. This change helps the motor to transition from starting with reduced current and higher torque (star) to operating at full speed and power (delta). It is a common method used to control the motor's performance characteristics during startup.
One must check the design of the transformer windings. STAR - Delta or Star to star or Delta - star or Delta Delta. Wiring must be done accordingly.
A star-delta motor should be supplied star-delta.Wye is simply another name for star. Star-delta motors use a star or wye configuration to start, and a delta configuration to run. This reduces the voltage on the windings during the high current starting time.
The Star-Delta control circuit diagram shows the delta contact and the main contact.
To shift from a star winding to a delta winding in a three-phase motor, the connections between the windings need to be rearranged. In a star winding, the ends of the windings are connected to a common point (neutral), while in a delta winding, each winding end is connected to the start of the next winding. By physically switching the connections, the motor can be reconfigured from star to delta winding.
the speed decrease if increasing load..in star connection the speed lower
when starting a 3 phase induction motor,first start with star connection,because reduced current is being applied and after start change it to delta connection then. full line current is applied to the motor.