HT and LT cables can be laid on same cable tray

1 Answers  

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What will happen to the protection and metering, if the polarity of a single or two PT/PTs in three phase system is reversed? Please provide reference if any.

0 Answers   Mind Tree,

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how many test is necessary for 27mva transformer.

3 Answers   HEG,

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why we use 25 kv in railway .not 11kv, or 33 kv

2 Answers   ISRO,

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we have a rewind motor of 2Hp,2800Rpm, 220Volt AC. how can we choose the running capacitor for this motor, any formula for that?

0 Answers  

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A CT is marked as 10VA 0.2FS in its name plate. What is it? Where it is used?

1 Answers  

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Reduction in supply voltage by 10% will change the torque of the motor by ___.

1 Answers   UGVCL Uttar Gujarat Vij Company Ltd,

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We have drive feeding an output contactor for a 5000 hp motor @ 5kV application. The motor FLA is 629amps x 1.25% service factor = 786.25 amps The cable that we current have in place between the drive and the output contactor is 350kcmil- MV-105 (parallel cables). Per the NEC table 310.60 (C) (69). This show the cable ampacity is at 615 amps per cable for a rating of 1230 amps. We have derated the cable for the cable tray and the multiple cables application and our calculations show that after the correction factor factor we are at 922amps. 1230 amps x .75% correction factor factor = 922.5 amps. The customer is driving us to then use another safety factor of .25% off of the already derated cable. Can you please provide a longhand calculation for your solution on this application?

0 Answers   Siemens,

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why dc supply is not applied for step up or down in transformer

3 Answers  

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It is a three inch fan and i want it to rotate to other direction .I've tried cutting the wire and reconnecting them inverse like black to white and white to black ,but it won't start rotating when i plug it in that way.And then it works again when i rejoin the wire to the way it is. I don't know what causing the problem.Is there anyone familiar with these small mortor?Any suggestion would be appreciated.Thanks!! http://i296.photobucket.com/albums/mm163/sasukebloodwheel/110527-105859.jpg

2 Answers  

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how the 12 pulse rectifier is made?

8 Answers   Engineers India Limited,

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For DG or Transformer body earthing, is it necessary to terminate the earth bus to earth pit directly? If not terminated to earth pit directly in earth pit and connected to any common bus strip which ultimately connects to earth pit, what will be the pros and cons?

1 Answers  

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