116 120

 116. What is the difference between earth resistance and earth electrode resistance?

Only one of the terminals is evident in the earth resistance. In order to find the
second terminal we should recourse to its definition: 
Earth Resistance is the resistance existing between the electrically accessible part of a buried electrode and another point of the earth, which is far away. The resistance of the electrode has the following
components :
( A) The resistance of the metal and that of the connection to it. 
(B) The contact resistance of the surrounding earth to the Electrode.

117. Which power plant has high load factor?

All base load power plants have a high load factor. If we use high efficiency power plants to supply the base load, we can reduce the cost of generation. Hydro power plants have a higher
efficiency than thermal & nuclear power plants.

118. Why an ac solenoid valve attract the plunger even though we interchanges the terminal?Will the poles changes?

Yes because the poles changes for every half-cycle of ac voltage so the polarity of AC voltage is continuously changing for every half cycle. 
So, interchanging of terminals in ac system does not show any difference. 
That's why the ac solenoid attract the plunger even though it's terminals are interchanged.

119. Define IDMT relay?

It is an inverse definite minimum time relay. In IDMT relay its operating is inversely proportional and also a characteristic of minimum time after which this relay operates. 
It is inverse in the sense, the tripping time will decrease as the magnitude of fault current increase.

120. What are the transformer losses?

TRANSFORMER LOSSES - Transformer losses have two sources-copper loss and magnetic
loss. Copper losses are caused by the resistance of the wire (I2R).Magnetic losses are caused by
eddy currents and hysteresis in the core. Copper loss is a constant after the coil has been wound
and therefore a measurable loss. Hysteresis is loss is constant for a particular voltage and current.
Eddy-current loss, however, is different for each frequency passed through the transformer.


Comments

Post a Comment

Popular posts from this blog

Electrical Electronics Communication Telecom Engineering Topics Explanation

Introduction to DC-TO-DC Converter  ||| Power Switching Devices Zones of Protection System And His Type  |||  There are six main causes of electric   |||   motor failures  |||  Top Electrical Engineering Interview Questions And Answers  |||  What Is Solar Panel  |||   How Does Solar Panel Work?  |||    What is Logical Circuit?  |||   What is Batter and Types of Battery?  |||   What is Current?   |||  What is Voltage?   |||  What Is Diode?     ||| Circuit Breakers and Rating Of CB  ||| Dry Type Transformers are Self-Extinguishing And Fire Resistant  |||  Kirchhoff's Laws  ||| Difference between AC and DC  ||| Define Amplitude, instantaneous value cycle, Time period, frequenc  ||| Common Causes of Electric Motor Failures   |||   All About Electric Motor  ||| Basic Concept Of Electrical Earthing and Groundin...
Read more

Electrical Transformers

 Electrical Transformers Principle of Electrical Transformers   Click To Read   Transformers Action       Transformers V.I Click To Read                         Click To Read   Transformers Magnetic Circuit                   Click To Read   Auto Transformer       Click To Read   Instrumental Transformer           Click To Read   Potential Transformers           Click To Read   Transformers Bush  Current Transformer       Click To Read                 Click To Read   Tap Transformers    Transformers Polarity       Click To Read                Click To Read   Single Phase Transformers Connections        ...
Read more

Electrical Engineering Top Interview Questions And Answers 50 t0 100

51: Explain the working principal of the circuit breaker? 52: In the motors starting purpose why the armature rheostats at maximum position while the field rheostat is kept in minimum position? 53: What is the significance of vector grouping in Power Transformers?   54: Advantages of vvvf drives over non vvvf drives for EOT cranes?   55: How can you start-up the 40w tube lite with 230v AC/DC without using any choke/Coil?   56: What is electric traction?   57: Why computer humming sound occurred in HT transmission line?   58: What's the one main difference between UPS & inverter ? And electrical engineering & electronics engineering?   59: What is meant by armature reaction?   60: What is Potential Transformer (PT)? 51: Explain the working principal of the circuit breaker?   52: In the motors starting purpose why the armature rheostats at maximum position while the field rheostat is kept in minimum position? 53: What is the significance o...
Read more