Why -48V dc power supply using in telecom field?

7 Answers   APC, Cisco,

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the resistance of wire having length X M is R OHEM if i streched the wire to dubble length what will be the resitance

3 Answers  

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Why are transmission lines multiples of 11? Is it because of some historic reason ? Or is there a scientific base to it?

5 Answers  

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which motors are used in electric traction?

1 Answers  

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what is meant by trip circuit supervision & directional or non directional over current ?

1 Answers   ABB,

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How can determine cable size with respect to cable length and area in mm2

1 Answers  

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Why do we need a separate control desk & PLC control panel in Boiler plant or coal handling plant? Can we provide cost effective Control desk cum PLC panel. Is there is an specific need for control desk.. kindly advice.

0 Answers  

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When dc supply is fed to rotor of the alternator how it work?

0 Answers  

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if i am in front of transmission line how to know that current direction without any equipment

0 Answers  

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What will be MF for below rating ? Main CT PT value is 11kva/110 and 20/5 amp Meter display is 1kva/110v and -/5 amp What will be MF ? Multiplycity factor of energy meter

0 Answers  

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Among the following Which is vector quantity? a. Flux b. permitivity c. flux density d. magnetic intensity

2 Answers  

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What is the test block protection relay if any body know plz explained

0 Answers  

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