Answer / harit

Overcurrent setting should be 120% of the Full Load Current of motor (time setting should be as per the recommendation of the manufacturer or Load characteristic)

instantaneous overcurrent & short circuit current settings should be 7 to 8 times of the full load current. Time interval to trip : should be set at zero (instantaneous).

what is threshold voltage for a relay???what does it exactly means ?whats its value in our indian transmission system say 11kv feeder RMU relay

3 Answers  

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how to test the turn ratio of 3 phase transformer using volt meter shoe the curcit diagram.

0 Answers  

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How to design the NGR Resistance

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What is Automatic Voltage regulator(AVR)?

6 Answers   Cummins,

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When we change the tap position of 10MVA transformer it suddenly tripped with Out of step indication and also with Static differential relay indication, Transformer Bucholz relay indn and Low oil level indication. Before 1 week the same problem occured by changing the tap position. but at that time only oltc bucholz relay activated. After testing the TxR Relay team & PET team cant find any solid reason. The values are ok also. So plz answer wat's the reason for this incident? anybody plz help.

3 Answers  

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we have 3 single phase transformers. how will we generate 6 supply from 3 phase supply input

0 Answers   NHPC,

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how much excitation voltage required to generate 1mw power?

0 Answers   Saudi Oger,

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why one side of tubelight glows after switch off ?

1 Answers  

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There are two nos of 33Kv/11Kv 5MVA transformers conecting through HT cable from substation having metering at substation itself.One transformer used at a time another remains stand by.Further 11 nos of 11Kv/440V transformers are attached on it and each transformer is having its own Power factor correction panel.Now one 33/11Kv transformer at no load condition/Stand by condition is having power factor in leading side upto 0.21 and while when another tranformer at same situation have power factor in lagging 0.42. Now one thing is clear that transformer one is having 1.5 Km long 33kv cable due to that PF goes in leading side and another is having only 250 mtr length remains him lagging. Now i want to know that how i can maintain the Power factor at no load/ stand by position though both are behaving in seperate manner.

1 Answers  

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dc supply given to dc generator winding.how is possible? my knowledge is saying the winding will burn. please reply.

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why the insulators are in cofee colour???

4 Answers   Visa Steel,

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when the PFR (POWER FACTOR REGULATOR)change a step to zero,one of the RCCB will triped off,is it the changing step of this PFR effect the RCCB?

2 Answers  

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