what is the effect when the shunt field winding is opened in dc shunt motor (i) at the time of starting ? (ii) in running condition ?

4 Answers  

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Difference between a pilot wire and a normal conductor?

0 Answers   United Arab Aluminum Company,

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Which supply is using for train AC or DC & what is the voltage????????

16 Answers  

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Why indicate only 440V to 3-phase supply.

4 Answers  

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How to select cable rating for HT/LT Panels

1 Answers   Alstom,

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why series motor cannot be started on no-load?

6 Answers  

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Electromagnetic torque developed by the motor is compared to shaft torque. A less B same C depends on motor design D more

3 Answers  

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What is power distribution criteria for converting single phase unbalanced residential load to 3 phase star connected balance system. Does total KW converted to 3 Phase. Means Divided by root 3.

0 Answers  

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wat is mean by HRC fuse... WHY we choose it...?

3 Answers  

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Any one can explain if there is any harm from humming noise heard from air circuit breaker : we have 415 switch board having two incomers from transformers 3.3KV/415V , when bus coupler closed, and open one ACB incomer to work in one of the transformers, the current started hunting around 50 Amps, and heard humming noise from the air circuit breaker, although the load current was only 1200 amps while the ACB capacity is 2500 Amps, and the transformer 1600 KVA. The same didn't happen when taken the other transformer offline. Why this humming noise and current fluctuation? is there any implication or danger, bearing in mind that we just returned everything back to normal and stopped the maintenance of the transformer. Shall we go ahead and ignore this noise?

6 Answers  

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Why does capacitor block dc supply?

5 Answers   Bhel,

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how much loading in terms of ampere can put on 5 MVA,33/11 KV TRANSFORMER having rated current 263 Amp ?????????

11 Answers   ABB,

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