Hi all I had applied for the RRB test in the ELECRICAL category. I would be pleased if any of you can sent me previous year question papers. Please forward the question papers to varshashahi@yahoo.com Thanks and regards Varsha

0 Answers  

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How can i learn to programme every VFD. Or is there any typical study to understand VFD programming.

1 Answers   Volkswagen,

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How to decide the fuse ratings for potential transformer

2 Answers   Eskom,

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Just a silly question but just to make my curious mind bac to normal - Why was not 67 and 67N relays built into a single relay as i have noticed that the R,Y,B CT wiring end up into the 67 relay while the common of the R,Y,B CT wiring end up into the 67N relay. Then it was better if a single relay was manufactured just like the distance relay (21). Another question i would like to ask is - how do we know where the 67 and 67 N relay has to be placed.why is it not placed at the transformer bay? In the substaion that i am working -i have noticed that it is placed between a breaker and a common double bus bar and this line bay is connected to another substation at a remote place which is furthur connected to a load. B U S______CT for 67 & 67N ______Breaker _____ remot s/s. B A R

1 Answers  

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In dc motor starter there is less voltage required for holding contactor that's may why it is called no volt coil. but in ac starter why holding contactor is called no volt coil.

2 Answers   JSW,

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formula for cable size calculation for current?

10 Answers   KL Power, ONGC, RL Clean Power Pvt Ltd RLCPPL, SAS, Sobha Developers,

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why a three phase transformer cant rotate like three phase motor

7 Answers  

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How to know the Max. current caring capacity of the cable by its size ?

0 Answers   SFPL,

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why synchronization done in clockwise direction?

12 Answers   Hindalco, NTPC,

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What is the formula for calculating impedance of transformers connected parallel at fault level 50KA?

0 Answers  

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What are :- AC Distribution Board (Single & Double Front) DC Distribution Boards Distribution Board LT Breaker Panel.

0 Answers  

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Why Two Transformers aside shoud be supperated by concreted wall?

5 Answers  

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