Recent questions tagged factor

Description : What Does Quality Factor Mean?

Last Answer : Answer :The Quality factor is also defined, as Q. So it is a number, which reflects the lossness of a circuit. Higher the Q, the lower are the losses.

Description : What is meant by Power factor?

Last Answer : Ans. Power factor means ratio of true power to apparent power. It is cosine of phase angle between voltage and current. Its value is 1 for Unity P.F. Loads, 0 to 1 lagging for inductive loads and o to 1 leading for capacitive loads.

Description : State the effects of low power factor on efficiency and voltage regulation of short transmission lines. 

Last Answer : i) Effect of Low power factor on efficiency:- When power factor of load reduces current drawn by transmission line increases so copper losses in transmission line increases, hence transmission ... increases, so voltage drop in transmission line increases so regulation increases. (Become Poor) 

Description : Briefly explain how the power factor of an inductive circuit can be improved.

Last Answer : As we know that power factor should be corrected to ensure that the current supplied is cost friendly. Meaning the power factor should be around one but not greater than one(0.8-0.9) in a ... an inductive circuit due to the inductive reactance which oppose the change of current in the ac circuit. 

Description : Define leakage factor.

Last Answer : It is the ratio of total flux to leakage flux.

Description : Define PIV, TUF, ripple factor, efficiency of rectifier.

Last Answer : PIV: Peak Inverse Voltage (PIV) is defined as the maximum negative voltage which appears across non-conducting reverse biased diode. TUF : Transformer Utilization Factor (TUF) is defined as the ratio of DC output ... Efficiency of rectifier: η = DC output power/ AC input power = PLdc / Pac

Description : working of distortion factor meter with block diagram

Last Answer : Working : Initially the switch S is kept at position 1.The attenuator gets excluded and the bridge T network is adjusted for full suppression of fundamental frequency and hence we get ... is obtained on the meter.Thus the total rms distortion is indicated by the reading of attenuator. 

Description : Why capacitors are used to improve power factor?

Last Answer :  Capacitors generate reactive power instead of that drawn from source which is required by inductive loads.so it reduce the reactive current which is drawn from source to be drawn from capacitor.This control in Electric bills cost.

Description : Define : i) Strain gauge ii) Gauge factor

Last Answer : i) Strain gauge is a resistance transducer whose resistance varies with applied force; It converts force, pressure, tension, weight, etc., into a change in electrical resistance which can then be measured ... is defined as the ratio of per unit change in resistance to per unit change in length 

Description : Define ripple factor and PIV of HWR

Last Answer : Peak Inverse Voltage (PIV) or Peak Reverse Voltage (PRV) refer to the maximum voltage a diode can withstand in the reverse-biased direction before breakdown. Also may be called Reverse Breakdown Voltage.

Description : Availability factor

Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }

Description : Discuss how power factor tariff results into energy conservation.

Last Answer : Power factor tariff results into energy conservation: i) Applying incentives and penalties according to power factor is an effective way, which enables consumer to improve power factor so that he can ... finally leads to reduction in the current drawn by the load and helps for energy conservation.

Description : Draw and explain bulk correction method for power factor & control.

Last Answer : Bulk correction method for power factor & control: i) Here individual starter controls the capacitors located at distribution panel. ii) Centralized compensation is employed in large industrial plants where many ... capacitor units in steps to maintain P.F. more than preset limit (0.95). 

Description : State the incentives and penalties related with power factor tariff.

Last Answer : Incentives and penalties related with power factor tariff: In addition to basic tariff (Maximum Demand Tariff / KVA Maximum Demand Tariff / Load factor tariff) the tariff in which P.F. of ... industrial consumer/H.T/ commercial consumers with contract demand above 80 kw/ 100Kva/107 hp consumer.

Description : With a neat sketch explain working of 1 phase dynamometer type power factor meter.

Last Answer : Working of 1 phase dynamometer type power factor meter : The current coil is connected in series with load. Two pressure coils marked as A and B are connected across the supply terminals ... becomes stationary and the pointer shows steady deflection corresponding to the power factor of the load. 

Description : State the significance of power factor.

Last Answer : Significance of power factor:-  1. Cosine of angle between voltage & current in a circuit is called power factor. 2. It is a measure of the real power in a circuit. 3. Inductive & ... KVA rating equipment 5. Greater conductor size 6. CosØ = R/Z  CosØ= Active Power/ Apparent Power 

Description : Define ripple factor and PIV of diode.

Last Answer : 1. Ripple factor: It is define as ratio of R.M.S. value of AC component to the DC component in the output.  2. PIV : It is maximum reverse voltage that diode can withstand without destroying junction.

Description : Define form factor and peak factor.

Last Answer : Form factor is equal to rms value divided by average value ... Peak factor is equal to Max value divided by rms value.

Description : The following formula is correct:  (A) Diversity factor =1 / Coincidence Factor  (B) Diversity factor =1 x Coincidence Factor  (C) Diversity factor =1 - Coincidence Factor  (D) All of the above

Last Answer : The following formula is correct:  (A) Diversity factor =1 / Coincidence Factor  (B) Diversity factor =1 x Coincidence Factor  (C) Diversity factor =1 - Coincidence Factor  (D) All of the above

Description : The following formula is correct:  (A) Load factor=Average load for a period/ Peak load for the same period  (B) Load factor=Average load for a period x Peak load for the same period  (C) Load factor=Average load for a period + Peak load for the same period  (D) All of the above

Last Answer : The following formula is correct: (A) Load factor=Average load for a period/ Peak load for the same period (B) Load factor=Average load for a period x Peak load for the same period (C) Load factor=Average load for a period + Peak load for the same period (D) All of the above

Description : A control system having unit damping factor will give  (1) Oscillatory response (2) Undamped response (3) Critically damped response (4) No response

Last Answer : 1

Description : Load factor is the  (1) Ratio of maximum load on the station to sum of consumer's maximum load.  (2) Ratio of average demand to maximum demand.  (3) Factor used for increasing load.  (4) Reciprocal of (1).

Last Answer : Load factor is the Ratio of average demand to maximum demand. 

Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

Description : The knowledge of diversity factor helps in computing  (1) Plant capacity (2) Average load (3) Units (kWh) generated (4) Peak demand

Last Answer : The knowledge of diversity factor helps in computing Plant capacity

Description : The load duration curve for unity load factor will be of  (1) Rectangular shape (2) Triangular shape (3) L -shape (4) I -shape

Last Answer : The load duration curve for unity load factor will be of Rectangular shape

Description : The power factor of dielectric :  (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)

Last Answer : The power factor of dielectric :  (A) is a function of temperature of the dielectric only (B) depends only on voltage stress to which the dielectric is stressed (C) always constant (D) both (A) and (B)

Description : In order to have a lower cost of electrical energy generation the load factor  (1) and the diversity factor should be low (2) should be low but the diversity factor should be high (3) should be high but the diversity factor should be low (4) and the diversity factor both should be high

Last Answer : In order to have a lower cost of electrical energy generation the load factor and the diversity factor both should be high

Description : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is  (1) 122.8 GWh (2) 198.55 GWh (3) 128.2 GWh (4) 188.82 GWh

Last Answer : Power station having Load factor = 70%, capacity factor = 50%, used factor = 60%, maximum demand = 20MW then annual energy production is 122.8 GWh

Description : In a synchronous generator delivering lagging power factor load  (1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) ... by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle

Last Answer : In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

Description : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Last Answer : What is the power factor when a single phase watt meter operating on 200 V and 5 A for 5 hours makes 2016 revolutions and the meter constant in revolution is 420? A) 0.04 B) 1.04 C) 0.96 D) None of these

Description : What is crest factor (peak factor)? A) It is the ratio of the maximum amplitude to average value B) It is the ratio of the average amplitude and RMS value C) It is the ratio of the maximum amplitude to RMS value D) None of these

Last Answer : What is crest factor (peak factor)? A) It is the ratio of the maximum amplitude to average value B) It is the ratio of the average amplitude and RMS value C) It is the ratio of the maximum amplitude to RMS value D) None of these

Description : Which of the following waveforms has the lowest form factor? A) Sine wave B) Square wave C) Sawtooth wave D) Triangle wave

Last Answer : Which of the following waveforms has the lowest form factor? A) Sine wave B) Square wave C) Sawtooth wave D) Triangle wave

Description : The benefit of power factor correction in a power system is (A) lower power consumption (B) increased demand charge (C) reduced load carrying capabilities in existing lines (D) reduced voltage profile

Last Answer : The benefit of power factor correction in a power system is lower power consumption

Description : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are (A) 0.5 pu ... pu, 0.5 pu (C) 0.707 pu, 0.707 pu (D) 0.5 pu, 0.5 pu

Last Answer : The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu from a lagging load are 45o and 15o, respectively. The direct axis and quadrature axis currents, respectively, are 0.866 pu, 0.5 pu

Description : The damping factor of a particular system is unity, the system response will be

Last Answer : The damping factor of a particular system is unity, the system response will be critically damped

Description : The power factor of a D.C. circuit is always?

Last Answer : The power factor of a D.C. circuit is always unity.

Description : The ratio of active power to apparent power is known as____ factor.

Last Answer : The ratio of active power to apparent power is known as power factor.

Description : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is?

Last Answer : The input of an A.C. circuit having power factor of 0.8 lagging is 40 kVA The power drawn by the circuit is 32 kW.

Description : Power factor of electric bulb is?

Last Answer : Power factor of electric bulb is unity.

Description : The power factor at resonance in R-L- C parallel circuit is?

Last Answer : since a rlc circuit at resonance behaves like a pure resistive circuit, i.e there is no phase difference between current and voltage, hence the power factor is unity.

Description : Power factor of the system is kept high?

Last Answer : Power factor of the system is kept high to reduce line losses, to maximise the utilization of the capacities of generators, lines and transformers, to reduce voltage regulation of the line.

Description : Power factor of an inductive circuit is usually improved by connecting capacitor to it in?

Last Answer : Power factor of an inductive circuit is usually improved by connecting capacitor to it in parallel.

Description : Capacitors for power factor correction are rated in?

Last Answer : Capacitors for power factor correction are rated in kVAR.

Description : Poor power factor?

Last Answer : Poor power factor reduces load handling capability of electrical system, results in more power losses in the electrical system, overloads alternators, transformers and distribution lines, results in more voltage drop in the line.

Description : Power factor of an electrical circuit is equal to?

Last Answer : Power factor of an electrical circuit is equal to R/Z, cosine of phase angle difference between current and voltage, kW/kVA.

Description : Form factor for a sine wave is?

Last Answer : 1.11

Last Answer : The form factor is the ratio of r.m.s. value to average value.

Last Answer : The power factor of a single phase load can be calculated if the instruments available are three ammeters or three voltmeters.

Last Answer : In a dynamometer 3-phase power factor meter, the planes of the two moving coils are at 120°.

Last Answer : In a single phase power factor meter the phase difference between the currents in the two pressure coils is exactly 90°.