Description : The number of electrical degrees ‘passed through’ in one revolution of a 6-pole synchronous alternator is: A) 360 degree B) 720 degree C) 1080 degree D) 2160 degree
Answer :
2
asked
Jun 17, 2018
by
anonymous
Description : 5(4+1) ÷ 5(5) = ?
Answer :
5(4+1)÷5(5) LHS= 5×4+5×1 20+5 =25 RHS= 5×5= 25 Therefore= 25÷25=1 QED=1
asked
Jul 14, 2019
by
anonymous
Description : Three resistors of 4 Ω, 6 Ω and 9 Ω are connected in parallel. Which resistor consumes the maximum power? (A) 4 Ω (B) 6 Ω (C) 9 Ω (D) 17 Ω
Answer :
(c) 9 ohm
asked
Apr 5, 2018
by
anonymous
Description : Draw block diagram of instrumentation system. State function.
Answer :
Primary transducer: The sensor which comes in contact with the measurement medium to sense the quantity. Variable conversion element: the transducer which converts the sensor ... transmitted through suitable transmission medium to the operator or presented with the help of indicators.
asked
Sep 8, 2018
by
anonymous
Description : The 8086 fetches instruction one after another from _____ of memory. (a) Code segment (b) IP (c) ES (d) SS
Answer :
A
asked
May 13, 2018
by
anonymous
Description : Compare individual and group drive on any four points.
Answer :
S.No. Point Individual Drive Group Drive 1 Definition In this type of drive each machine has its own separate electric drive (motor). It may be directly coupled ... Lathe Machine (Similar application will be consider) Textile Industry (Similar application will be consider)
asked
Oct 12, 2018
by
anonymous
Description : Explain with neat diagram construction and working of Ajax Wyatt vertical core induction furnace.
Answer :
Neat sketch of Ajax Wyatt' vertical core furnace: Construction of Ajax Wyatt' vertical core furnace: Vertical core type induction heating furnace is nothing but transformer. It consists of ... is utilized to melt the charge. Where, R = Resistance of charge & I secondary current.
asked
Oct 13, 2018
by
anonymous
Description : Describe the difference between an open circuit and a short circuit.
Answer :
Open circuit means the wire is cut meaning power will not flow and close circuit means wire is not cut and hence power will flow.Short circuit is the same as close circuit
asked
Jun 29, 2019
by
anonymous
Description : Can you answer this question? X + X + X = 30 X + Y + Y = 20 Y + Z + Z = 17 X + Y + Z = ?
Answer :
X+Y+Z =21 10+05+6=21
asked
Jul 16, 2019
by
anonymous
Description : Which device use to convert DC to AC?
Answer :
Rectifier
asked
Dec 9, 2017
by
anonymous
Description : Which of the following is not a basic element of a transformer ? 1. Core 2. Primary winding 3. Secondary winding 4. Mutual flux
Answer :
A
asked
May 13, 2018
by
anonymous
Description : List the different errors in wattmeter & explain compensation for it.
Answer :
Errors in Wattmeter Compensation method Error due to connection method To overcome this error, wattmeters are provided with additional compensating winding which is connected in series with ... due to friction The weight of moving system be reduced to minimum possible.
asked
Sep 5, 2018
by
anonymous
Description : The size of a conductor used in power cables depends on the: (A) operating voltage (C) current to be carried (B) power factor (D) type of insulation used
Answer :
The size of a conductor used in power cables depends on the: current to be carried
asked
Apr 9, 2018
by
anonymous
Description : Draw the diagram and explain the working of ferrodynamic type frequency meter.
Answer :
Ferrodynamic type frequency meter: (Electrical resonance type frequency meter): It consists of a fixed coil. The supply whose frequency is to be measured is connected across it. This coil ... so selected that the moving coil takes up a convenient position when frequency is of normal value.
asked
Sep 6, 2018
by
anonymous
Description : A 6-pole, 50Hz, 3-φ induction motor is running at 950 r.p.m. and has Cu loss of 5kW. The rotor input is (a) 10 kW (b) 95 kW (c) 100 kW (d) 9.5 kW
Answer :
s=(Ns-N)/Ns =(1000-950)/1000=0.05.rotor cu.loss= s*rotor inputwe have rotor cu loss=5kWtherefore, rotor input= rotor cu.loss/s =5kW/0.05 =100 kW
asked
May 25, 2018
by
anonymous
Description : Moving iron instruments can be used for measuring (1) Direct currents and voltages (2) Radio frequency currents (3) A.C currents and voltages (4) Both (a) and (c)
Answer :
moving iron instruments areused to measure A.C curents & voltages
asked
Apr 11, 2018
by
anonymous
Description : An Auto-transformer (which has only one winding) may be used as a ______ . (A) Both Step-Up and Step-Down transformer (B) Step-Down Transformer (C) Step-Up Transformer (D) None of these
Answer :
an autotransformer may used only as step down transformer
asked
May 8, 2018
by
anonymous
Description : A 120 Ah capacity battery can deliver a current of 8A for a period of
Answer :
A 120 Ah capacity battery can deliver a current of 8A for a period of 15
asked
May 14, 2018
by
anonymous
Description : Write difference between absolute & secondary instrument.
Answer :
Absolute Instrument Secondary Instrument 1. These give magnitude of quantity in terms physical constants of instruments 1. These give reading directly of the quantity at the time of ... Raleigh current balance. 6. Examples - ammeter, voltmeter, amperehour meter, wattmeter etc.
asked
Sep 5, 2018
by
anonymous
Description : Poynting vector wattmeter is based on (A) Seebeck effect (B) Ferranti effect (C) Induction effect (D) Hall effect
Answer :
Poynting vector wattmeter is based on Induction effect
asked
May 17, 2018
by
anonymous
Description : The severity of line to ground and three phase faults at the terminals of an unloaded synchronous generator is to be same. If the terminal voltage is 1.0 pu, Z1=Z2=j0.1 p.u. and Z0= j0.05 p.u. for the alternator, then the required inductive reactance for neutral grounding is (a) 0.05 p.u. (b) 0.0166 p.u. (c) 0.1 p.u. (d) 0.15 p.u.
Answer :
The severity of line to ground and three phase faults at the terminals of an unloaded synchronous generator is to be same. If the terminal voltage is 1.0 pu, Z1=Z2=j0.1 p.u. and Z0= j0.05 p.u. for the alternator, then the required inductive reactance for neutral grounding is 0.0166 p.u.
asked
May 13, 2018
by
anonymous
Description : The most efficient method of increasing the speed of a 3.75KW d.c. shunt motor would be A) Armature control B) Flux control C) Ward—Leonard D) Tapped—field control
Answer :
Flux control
asked
Apr 9, 2018
by
anonymous
Description : what is lightning arrester?
Answer :
Light arrester is a protecting device which is used at substation for protecting the devices in the substation from lighting phenomenon.
asked
Nov 30, 2017
by
anonymous
Description : Why high voltage is used in power transmission?
Answer :
The primary reason that power is transmitted at high voltages is to increase efficiency. ... The lower current that accompanies high voltage transmissionreduces resistance in the conductors aselectricity flows ... This means that thin, light-weight wires can beused in long-distance transmission.
asked
Mar 10, 2018
by
anonymous
Description : Draw the block diagram of basic wind energy conversion system and write function of each block.
Answer :
Block diagram of basic wind energy conversion system: OR Components of wind power plant and their functions: 1) Rotor /Blade/Aero-turbine: Blade extracts significant power from the ... stronger and smoother. Towers are supports to raise the main part of the turbine up in the air.
asked
Sep 8, 2018
by
anonymous
Description : Describe the difference between direct and alternating current.
Answer :
Direct current is the flow of electricity or charge in one direction.. Alternative current is the flow of charge that doesn't flow in one direction.
asked
Jun 29, 2019
by
anonymous
Description : With a neat diagram explain doubly fed induction generator (DFIG).
Answer :
Diagram of Doubly fed induction generator (DFIG): Explanation :- DFIG can feed power through the stator as well as rotor to the grid. The stator is directly connected to the fixed frequency ... voltage is 690 V AC. So it must be step up to 33 KV to connect to power grid.
asked
Jul 24, 2019
by
anonymous
Description : Write two application of the following motor (i) AC servo motor (ii) Stepper motor
Answer :
(i)Applications of AC Servo Motor: 1. Computers 2. Robotics and toys 3. CD/DVD players 4. Textile industries 5. Instrument servos 6. Tracking and guidance system 7. Self- ... Laser cutters 20.Extruders 21.Engravers 22.Analytical and Medical instruments 23.Embroidery Machines 24.Packeging Machines
asked
Jul 20, 2019
by
anonymous
Description : What is the difference between relay and contactor?
Answer :
Relay have smaller ratings. Contactor is a high rating relay.
asked
May 2, 2018
by
anonymous
Description : Is the power line voltage available in our homes a dc or an ac voltage?
Answer :
The power line voltage available in our homes is AC. Mobile dwellings are the most commonly DC-supplied homes and even then they tend to include AC supply for heavier loads.
asked
Jun 29, 2019
by
anonymous
Description : List advantages and disadvantages of CNC based drilling machine.
Answer :
Advantages : Reduce the making/production cost Increases the productivity CNC improves the production Low skill operator is required High accuracy and repeatability Complex machining operations are also ... Its replacement is difficult, that it is difficult to change old system to new system
asked
Jul 21, 2019
by
anonymous
Description : Draw a circuit diagram of R.C. series circuit. Draw impedance triangle and power triangle for same circuit.
Answer :
Draw a circuit diagram of R.C. series circuit. Draw impedance triangle and power triangle for same circuit.
asked
Jul 10, 2019
by
anonymous
Description : Describe Twin-tube process with diagram.
Answer :
Twin Tub Process: A logical extension of the p-well and n-well approaches is the twin-tub fabrication process. In this process, a substrate of high resistivity of n-type material ... manufacturing tolerances results. This is particularly important as far as latch up is concerned.
asked
Jul 21, 2019
by
anonymous
Description : Explain differential protection of busbar.
Answer :
Differential protection Scheme for bus bar: Under normal conditions the sum of the currents entering the bus bar zone is equal to those leaving it and no current flows through the relay ... . The difference of these currents will flow through the relay coil causing opening of circuit breaker.
asked
Jul 21, 2019
by
anonymous
Answer :
Because India uses 220-230volt In USA there they uses 110volt
asked
Jul 12, 2019
by
anonymous
Description : Describe the construction of any one type of capacitor.
Answer :
i) Air capacitors: Air capacitors are capacitors which use air as their dielectric. The simplest air capacitors are made of two conductive plates separated by an air gap. Air capacitors can be made in ... axial form. Essentially the leads either exit the encapsulation at the side or the end.
asked
Jul 5, 2019
by
anonymous
Description : What is the 2's complement of 01101? A) 10010 B) 10011 C) 1100 D) 1001
Answer :
What is the 2's complement of 01101? A) 10010 B) 10011 C) 1100 D) 1001
asked
Jun 17, 2018
by
anonymous
Description : What is the function of an electrical filter ?
Answer :
Filter separates different components that are mixed together. Electrical filter can separate different frequency components. Electrical filters are the electrical circuits which are use to remove unwanted frequency components from the signal.
asked
Jun 1, 2019
by
anonymous
Description : State reason BJT is called as bipolar junction transistor.
Answer :
BJT is called bipolar junction transistor because in BJT current conduction takes place due to majority as well as minority charge carriers.
asked
Jul 24, 2019
by
anonymous
Description : If we tossed simultaneously two coins. Find the probability of exactly one tail.
Answer :
If we toss two coins simultaneously,there are four possible outcomes HEAD-HEAD TAIL-TAIL HEAD-TAIL TAIL-HEAD so probability of getting exactly one tail=2/4=1/2
asked
Jul 14, 2019
by
anonymous
Description : Draw and explain electronic PID controller.
Answer :
Diagram :
asked
Jul 21, 2019
by
anonymous
Description : Write down limitation of differential protection of transformer.
Answer :
Limitations of differential protection of transformer: 1) Due to the magnetization characteristics of the CTs used, the ratio errors change with respect to the circulating currents. 2) The pilot wires ... current (higher imbalance) due to which accuracy of sensing & operation is decreased.
asked
Jul 21, 2019
by
anonymous
Description : Without any additional circuitry, an 8:1 MUX can be used to obtain: (1) Some but not all Boolean functions of 3 variables (2) All function of 3 variables but none of 4 variables (3) All functions of 3 variables and some but not all of 4 variables (4) All functions of 4 variables
Answer :
A
asked
Apr 9, 2018
by
anonymous
Description : Application of Norton's theorem to a circuit yields : (A) Equivalent current source only (B) Equivalent voltage source only (C) Equivalent voltage source and impedance in series (D) Equivalent current source and impedance in parallel
Answer :
B
asked
Apr 14, 2018
by
anonymous
Description : Shunt compensation in an EHV line is used to (A) Improve stability. (B) Improve the voltage profile. (C) Reduce the fault level. (D) Substitute for synchronous phase modifier.
Answer :
Shunt compensation in an EHV line is used to Improve the voltage profile.
asked
May 8, 2018
by
anonymous
Description : In an alternator if the winding is short pitched by 60 electrical degrees, its pitch factor will be: A) 1.0 B) 0.866 C) 0.75 D) 0.50
Answer :
In an alternator if the winding is short pitched by 60 electrical degrees, its pitch factor will be: A) 1.0 B) 0.866 C) 0.75 D) 0.50
asked
Jun 4, 2018
by
anonymous
Description : A negative sequence relay is commonly used to protect (A) an alternator (B) an transformer (C) a transmission line (D) a bus bar
Answer :
A negative sequence relay is commonly used to protect an alternator
asked
May 25, 2018
by
anonymous
Description : Differentiate between core type and core less induction furnace.
Answer :
Sr.No. Core type induction furnace. Core less induction furnace. 1 Less leakage flux More leakage flux 2 Power factor is good Power factor is poor 3 ... normal frequency is used. Due to high frequency, high voltage supply, time required for heating is less.
asked
Oct 13, 2018
by
anonymous
Description : The diagonal elements of a nodal admittance matrix are strengthened by adding : (A) Shunt capacitors (C) Generators (B) Shunt inductances (D) Resistive loads
Answer :
A
asked
Apr 30, 2018
by
anonymous
Description : What does the AND gate do?
Answer :
AND gate multiple two inputs. If any one input is zero output will be zero if both inputs are one then only output is one.
asked
Dec 15, 2017
by
anonymous