metres
A lot of designers will fit an under rated star contactor, partly for cost saving purposes and partly down to the fact that the star contactor will only stay energised for a brief period. Burning out the star contactor could be down to it staying in circuit too long, not changing over to delta, a timer malfunction holding in the star contactor or switch that is defective in the control circuit. Another cause could be your motor is drawing excess current.
The N.C. (timed open) contacts in the star delta timer energize the star contactor's coil when the system is energized. At the same instant the system is energized, the timer starts to time down the required time which lets the motor get up to speed in the star configuration. When the timer reaches the set point time, a second set of N.O. (timed closed) contacts close the delta contactor's coil and open the N.C. timed contacts of star contactor's coil. The motor now runs in the delta configuration. When the system is de energized the timer contact's reset to its de energized state.
yes
how to calculate injection molding m/c capacity
A definite purpose contactor is designed (and rated) for a specific load. So a lighting contactor is one example of a definite purpose contactor. A motor starter contactor is another example. So, a lighting contactor is a definite purpose contactor, but a definite purpose contactor is not necessarily a lighting contactor (it might be a motor starter, for instance).
A lot of designers will fit an under rated star contactor, partly for cost saving purposes and partly down to the fact that the star contactor will only stay energised for a brief period. Burning out the star contactor could be down to it staying in circuit too long, not changing over to delta, a timer malfunction holding in the star contactor or switch that is defective in the control circuit. Another cause could be your motor is drawing excess current.
The link in the star contactor is used to form the star point of three of the motor leads. On most star wound motors the star point is inside the motor windings. On a motor that can be used for star delta starting it is a six wire motor. The star point winding depends on the contactor to tie the coil ends together externally in the control panel of the star delta starter.
The timer is used to give the motor time to reach its running speed at the star voltage. Once the timer times out the star contactor drops out and the delta contactor pulls in.
That is the star point contactor that opens when it goes into the delta configuration.
The N.C. (timed open) contacts in the star delta timer energize the star contactor's coil when the system is energized. At the same instant the system is energized, the timer starts to time down the required time which lets the motor get up to speed in the star configuration. When the timer reaches the set point time, a second set of N.O. (timed closed) contacts close the delta contactor's coil and open the N.C. timed contacts of star contactor's coil. The motor now runs in the delta configuration. When the system is de energized the timer contact's reset to its de energized state.
240 or 415
how to calculate the embroidery machine capacity and Embroidery factory capacity and efficiency.
yes
how to calculate injection molding m/c capacity
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.
The capacity of Red Star Stadium at Belgrade in Serbia is 55,538.
A calorimeter can be used to calculate specific heat capacity.