Answer / k.prakashchandra

You can test-run motor with 1 phase supply treating it as a
capacitor start/ run 1 phase motor.There are 6 leads a1,a2&
b1,b2 &c1,c2 of each phase.Short a2 and b2 and connect it to
neutral. Give phase directly to a1 or b1 ,and give supply to
the other trough a suitable capacitor.Similarly, change the
phases

please tell me formula of 3 phase induction motor under condition{1]when we 3 phase motor starts without load in star or delta connection?thanks

1 Answers  

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if we increase the frequency given to a transformer then wat will happen to the transformer size, whether it will increase?

4 Answers  

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How to know the back up time for a 5KVA UPS which is connected to 15 nos. of computers? Is there any formula for this? pls. tell me.

1 Answers   HAL,

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Why is remote backup preferred to local backup?

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What is the need of earthing transformer for delta side of a transformer. (Think of a line section between a star/delta transformer at a grid substation and delta/star transformer at a village. An earthing transformer is there at the delta side of the star/delta transformer at grid substation). As there are no ground reference there will not be fault current if a one phase is grounded. Further L-L phase will be sensed by the primary side of star/delta transformer as a L-G fault. So why an earthing transformer is required at delta side

0 Answers   CEB,

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In some countries it is found that an Earthing Transformer is connected at the LV sides of the Transmission and Distribution Substation Transformers.Actually what is the purpose the Earthing Transformer?

1 Answers  

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If a high resistance fault occurs,then what are the changes will happen in the system?

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how to find out this one mcb r mccb?

4 Answers   L&T,

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How we can calculate the life of Lead acid battery

0 Answers   ABC,

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what is RTD? what is THERMOCOUPLE? What is difference between it?

2 Answers   Bhel,

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what is meant by loss of field in a DC motor? how a universal motor works?

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in a dc shunt motor what happens if motor takes high current,no speed

2 Answers  

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