How to set the various setting value of a relay depend upon the electrical motors ?

Nishant Choudhary

 Profile Answers by Nishant Choudhary Questions by Nishant Choudhary

• Jun 3rd, 2011

Its very simple first note the current rating of the motor on the name plate then adjust the current setting just above the name plate motor of the motor

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raviiisc

 Profile Answers by raviiisc Questions by raviiisc

• Jun 9th, 2011

It is due to the interaction of one flux and one current.For example in Motor (induction motor 3-phase), the stator flux interacts with the rotor current leads to torque development.Somebody also says...

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What is a ferroresonant transformer and what is its working principle?

Nishant Choudhary

 Profile Answers by Nishant Choudhary Questions by Nishant Choudhary

• Jun 3rd, 2011

Ferroresonant transformer are constant voltage transformer they maintain the output power to constant for any variation in input

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For 600 MW Generation Purpose.

raviiisc

 Profile Answers by raviiisc Questions by raviiisc

• Jun 9th, 2011

It will be 30 to 45 degrees.We wont allow the generator to operate at its maximum power transfer such as 90 degrees.At this the reactive power supplied by generator is the leading reactivepower. But w...

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What are contactors and why are they used in circuits can they protect the system from fault current ?

Ibrahim Baklawa

• Jul 20th, 2011

1st. what type of fault current? we have lot of faults.. for ex. over load, short circuit, earth fault we can use: over load relay. fuses. toroid. CB with over current and short circuit protection. CT...

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what is the purpose of zig zag transformer? . How it is different from normal transformer?

suresh

• Jul 29th, 2011

A Zigzag transformer is a special purpose transformer with a zigzag arrangement. It has primary windings but no secondary winding. One application is to derive an earth reference point for an ungrounded electrical system. Another is to control harmonic currents

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engineerfaisal

 Profile Answers by engineerfaisal Questions by engineerfaisal

• Mar 20th, 2009

Demand-side management (DSM) programs consist of the planning, implementing, and monitoring activities of electric utilities that are designed to encourage consumers to modify their level and pattern of electricity usage.

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Why can't the photo diodes produce large amperes of current? are there any large photo diodes producing current more than milli amps??

sameh

• Jun 28th, 2015

This is depend on the type and amount of the material that used in the diode to the materials used cant produce high current

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Why the capacitors are connected in delta? What advantage it having than star connection?

bittu123

 Profile Answers by bittu123 Questions by bittu123

• Nov 8th, 2011

Prime reason : Delta connection will give 3 times more reactive power(kVARs) than star connection.

there are few more reason....
1. less triplen harmonic
2. less heat loss, since current is I/1.732 where I will be the current star connection pr phase

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which is bigger in size AC or DC, of same rating?
As I think DC is right answer but HOW? Explain?

Pasupulati. V. N. Sekhar

• Jan 17th, 2012

The main difference in the size come because of the set up that is present in the DC machines i.e., in order to tap DC voltage generated we require the set up such as Commutator and brush arrangement ...

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Why many people do not connect the APFC/Capacitors in DC circuit?

KKMSURESH

 Profile Answers by KKMSURESH Questions by KKMSURESH

• Apr 8th, 2009

APFC means Automatic Power Factor Controller. Power Factor is applicable only in an AC Supply, DC is one of direct current, there is no Power Factor in DC Supply.

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shareek

• Nov 19th, 2007

firstly DIV means division. know 100V/DIV or 50A/DIV are usually the scales that are read on the OSCILLISCOPE. so if you see a waveform and you  have the scale set to 100v/DIV, it means that if y...

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s.v.vijayaraj

 Profile Answers by s.v.vijayaraj Questions by s.v.vijayaraj

• Apr 19th, 2008

           It is simple to find the teriminals in the SCR and Transistor, Where the SCR is in Flat package Transistor in metal can package.Also the th...

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s.v.vijayaraj

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• Apr 21st, 2008

Introduction Particle swarm optimization (PSO) is a population based stochastic optimization technique developed by Dr. Eberhart and Dr. Kennedy in 1995, inspired by social behavior of bird flocking o...

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Why people say that "When we want to send information (transfer from one pint to another) we modulate the signal below or above the center point (reference point)?1) By modulation we mean what?2. Why it is necessary to modulate signal for information center.3) Why more the modulation more informative can be send?

Eng. Maged saber

• Jan 17th, 2013

Modulation methods used because of when I need to transmit signal with low frequency it need long antenna as frequency inverse proportion with wave length and Wave length is in direct proportion with ...

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1-what is signal?2-What is Gsm?3-What about AMPS?4-What EDGE?5-What is GPRS?6-What is Ciphering?7-Difference Between Noise and Attenuation?

rahulr30

 Profile Answers by rahulr30 Questions by rahulr30

• May 30th, 2008

GSM-The Global System for Mobile Communications (GSM)GPRS-General Packet Radio ServiceEDGE -Enhanced DataRates for GSM Evolution

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What is Magnetic Levitation ?How MAGLEV (Trains based on Magnetic Levitation) works ?

arunkpkrn

 Profile Answers by arunkpkrn Questions by arunkpkrn

• Apr 15th, 2008

Magnetic levitation, maglev, or magnetic suspension is a method by which an object is suspended with no support other than magnetic fields. But train operating on Magnetic levitation is unknown to me.

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Whats happens when we give DC to a induction motor

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haveasafeday  

 Profile Answers by haveasafeday Questions by haveasafeday

• Member Since Feb-2008 | Feb 5th, 2008

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In dc there is no rotating magnetic flux which is required to rotate ac motor. if we apply dc to ac motor, it may burn.

haveasafeday

 Profile Answers by haveasafeday Questions by haveasafeday

• Feb 5th, 2008

In dc there is no rotating magnetic flux which is required to rotate ac motor. if we apply dc to ac motor, it may burn.

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Why we cannot use the capacitive load?

haveasafeday

 Profile Answers by haveasafeday Questions by haveasafeday

• Feb 5th, 2008

Capacitive load means a load with leading power factor which is very rare in electrical equipment.though syncronous motor is used as a capacitive load.

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What is the flyback convertor?

Harita

• Feb 18th, 2017

Flyback converter is a buck boost converter used in the SMPS (Switch Mode Power Supply, small size and large frequency)

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