If the voltage applied across the armature of a DC shunt motor is increased by 5% keeping its load current and field constant, what will be the effect on its speed? * increase by 10 per cent decrease by about 5 per cent increase by about 5 per cent remain unchanged

If the voltage applied across the armature of a DC shunt motor is increased by 5% keeping its load current and field constant, what will be the effect on its speed? * increase by 10 per cent decrease by about 5 per cent increase by about 5 per cent remain unchanged

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter43: About Dc Motors

Section: Chapter Questions

Problem 1SQ

See similar textbooks

Related questions

Q: A 220 V dc shunt motor takes 5A and 40A at no load and full load respectively. It has an armature…

A: Given: A DC shunt motor having Voltage supply, V=220 V No load current, IL0=5 A Full load current,…

Q: A 10hp, 230V, 1200 rpm DC series motor has the total armature circuit resistance Ra + Rf = 1.1Ω. The…

Q: A 25-kW, 230-V shunt motor has an armature resistance of 0.11Ω and a field resistance of 117Ω. At no…

A: A 25 kW, 230 V shunt motor has armature resistance Ra=0.11 ohm field resistance Rf=117 ohm At no…

Q: A 220 V, 7 A, 1100 rpm DC shunt motor has armature and field resistance of 1.75 02 and 250 n…

Q: A 230-V shunt motor draws 5 A at a no-load speed of 2400 rpm. The shunt- field resistance is 115 0,…

A: In the DC shunt motor, 230V, At no load draw current 5A, No load speed No= 2400 rpm Field…

Q: calculate the torque in newton metre developed by a 440v dc motor having an armature resistance of…

A: To calculate the torque

Q: A 30 hp, 240 V, 1150 rpm DC shunt motor, operating at rated conditions, has an efficiency of 88.5…

A: Given:Pout=30hp=30×746Pout=22380WV=240VoltN=1150 rpmη=88.5%Ra=0.064ΩRf=93.6Ω

Q: At 50% of full load, the armature current drawn by a dc shunt motor is 40 A when connected to a 200…

Q: A 10kW, 250V DC shunt motor has an armature resistance of 0.5 ohms and field resistance of 200 ohms.…

A: Soln GivenIsh = 250200= 1.25Aat no luadIa0 = 3A , N0=1200 rpmEb=VT-IaRaEb0= 250-3×0.5 = 248.5 Vat…

Q: Q6 A 250 V shunt motor on no-load runs at 1000 r.p.m. and takes 5 A. the total armature and shunt…

A: Note: We are authorized to answer the first question since the exact one wasn’t specified. Please…

Q: 1-The main disadvantage of Rheostatic control method of a dc shunt motor, that the speed up to zero…

A: In this question , some statements are given related to dc machines , we have to find out that they…

Q: The armature of a 270V dc shunt motor has a resistance of 0.20 ohm. If the armature current is not…

A: Note: We are authorized to answer three subparts at a time since you have not mentioned which part…

Q: A 4-pole, 240-V., wave-connected shunt motor gives 11.19 kW when running at 1000 rpm and drawing…

Q: A 200V DC shunt motor takes current of 10A when running unloaded. Its armature and shunt field…

Q: A 3000 V, 3 phase synchronous motor running at 1500 rpm, has its excitation kept constant…

A: An alternator/Synchronous generator is a type of electrical machine that converts mechanical energy…

Q: For the armature controlled DC motor shown, find the transfer function. Assume the following…

A: Solution

Q: 2) A 220V shunt motor draws 10A at 1800 rpm. The armature-circuit resistance is 0.2 N, and the…

A: Back emf = terminal voltage- drop in armature. Developed power is the product of back emf and…

Q: A DC shunt motor with interpoles has the following particulars : Output power ; 8,952 kW, 440-V,…

Q: A certain dc motor has RA=1.3 Ω, IA=10 A and produces a back emf EA=240 V, while operating at a…

A: Given data: The value of RA is: 1.3Ω The value of IA is: 10 A The value of EA is: 240 V The…

Q: R, DC U=230 V E (M

A: Given data: Ra=3 Ω N=1850 rpm Kbϕ=0.04 Transistor on time = 10 msec Transistor off time = 15 msec…

Q: 120V dc shunt motor has an armature resistance of 0.25Ω is drawing 50A. If a fixed loss of 200W was…

A: A dc shunt motor has, Terminal voltage ( Vt) = 120 V Armerture resistance (Ra) = 0.25 ohm Line…

Q: A 250 volt DC shunt motor has armature resistance of 0.25 ohm on load it takes an armature current…

A: In this answer we will find the new speed of the motor using the formulae as explained below.

Q: 2000rpm, 240V DC shunt motor has armature resistance of 0.80 and the field resistance is XQ. When…

Q: A 30 hp, 240 V, 1150 rpm DC shunt motor, operating at rated conditions, has an efficiency of 88.5…

A: Given p=30 hpV=240 VN=1150 rpmRa=0.064 ΩRf=93.6 Ω

Q: A 440 V, dc shunt motor has a rated armature current of 76 A at a speed of 1000 rev/min. The…

A: “Since you have posted a question with multiple sub-parts, we will solve the first three subparts…

Q: A 240V shunt motor, running on no-load and at normal speed, takes an armature current of 2.4 A from…

Q: 220v dc shunt motor takes a total current of 80A and runs at 800r.p.m. Shunt field resistance and…

A: Given DC Shunt motor V=220 vIL=80 ASpeed N=800 rpmShunt field resistanceRsh=50 ΩArmature…

Q: A 250 Volts shunt motor has an armature resistance of 0.5 ohm and a field resistance of 250 ohms.…

Q: (b) A 480 V, 100 kW, 50 Hz, four-pole, Y-connected synchronous motor has a rated power factor of…

A: Use the power flow diagram and then solve as below

Q: A 230V dc shunt motor has armature and field resistances of 0.3 W and 140 W respectively. Calculate…

A: A DC shunt motor is a form of self-excited DC motor in which the field windings are shunted to or…

Q: A dc shunt motor has a full-load rating of 240 volts, 1,500rpm, 20 HP, and 50 Amperes. The armature…

Q: A 25 kW, 230 V shunt motor has an armature resistance of 0.11 Q and a field resistance of 117 Q. At…

A: Fig: Given shunt motor circuit diagram Given that P=25 KW no load…

Q: Determine the back emf generated in the dc shunt motor if it takes 250 V, 41 A current while running…

A: Determine the back emf generated in the dc shunt motor if it takes 250 V, 41 A current while running…

Q: In a 5 HP, 230 V, 1500 rpm shunt motor, the resistance of the armature including brushes is 0.175…

A: According to the question we have to calculate the value of efficiency.

Q: 5. What is the difference between Self Excited and Separately Exited DC motor? 6. We know there are…

Q: 600V, DC series motor operates at 600 rpm and rated load. Armature resistance 0.1 ohm and series…

Q: نقطة واحدة Indicate whether the following * statement are true or false False True The…

A: Consider the list for the characteristic curve is shown below. (i) Torque vs armature current…

Q: E1. Which of the following is the correct equation to determine the armature current of a DC shunt…

Q: 220v dc shunt motor takes 5a and 40a at no load and full load respectively it has an armature…

Q: A 107 hp, 257 V dc shunt motor has the magnetization curve in the graph. The armature circuit…

A: Given a 107 hp =79.7 kW, 257 V dc shunt motor has the magnetization curve in the graph. The armature…

Q: A DC series motor of 240 V as input voltage has an armature resistance of 0.5 N and a field…

A: Given DC series motor of Input voltage V=240 vArmature resistance Ra=0.5 ΩField resistance Rf=10…

Q: A 500 Volts, 10 hp shunt motor has a full-load efficiency of 85%. With the same field and armature…

Q: 4 A shunt DC motor is operated at no-load at rated voltage 220 V, speed 1700 rpm and armature…

Q: A 220 V, 7 A, 1100 rpm DC shunt motor has armature and field resistance of 1.750 and 250 n…

Q: A 550-volt long-shunt compound motor has armature an resistance of 0.815 ohm and a series field…

A: The solution is given below.

Q: Q/ When a series dc motor is operated at load, which of the following conditions occurs Ans 1- The…

A: An easy question based on subject electrical machines. In this we are given one problem of theory in…

Q: Question 2 A 120-V DC motor rated at 5-hp has a full load efficiency of 86% The field and armature…

A: A DC motor is a machine which takes DC electrical energy and produces mechanical output at its…

Q: a). Speed characteristics of dc series motor along with suitable diagram. b). Speed characteristics…

A: This question is from " ELECTRICAL MACHINE". Under which we are going to study about the performance…

Q: When loaded at the nominal power of a DC shunt motor with pole voltage of 380V 3 kW, its efficiency…

Concept explainers

DC Series Motors

A DC motor is a type of electric motor which converts electric energy into mechanical energy. The forces that are produced by the magnetic field are what those common types of motors rely upon. Either electro-mechanical or electronic, all types of DC motors have some internal mechanism to change the current direction in part of the DC motors. As the DC motors could be powered from existing DC lighting power distribution systems, these motors were the first form of motors widely used. By changing the strength of the current in its field winding or by using a variable supply voltage, the speed of the DC motors can be controlled over a wide range.

Question

If the voltage applied across the
armature of a DC shunt motor is
increased by 5% keeping its load current
and field constant, what will be the effect
on its speed? *
O increase by 10 per cent
O decrease by about 5 per cent
increase by about 5 per cent
O remain unchanged

Expert Solution

This question has been solved!

Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.

SEE SOLUTION Check out a sample Q&A here

Step 1

VIEW

Step 2

VIEW

Step by step

Solved in 2 steps

SEE SOLUTION Check out a sample Q&A here

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.

Similar questions

A 55 hp, 440 V, 400 rpm DC shunt motor draws 107 A when operating at rated conditions. The motor has an armature-circuit resistance of 100 mW and a total field-circuit resistance of 55 W. Draw a schematic of the motor in the space below showing all known quantities (resistances, currents, voltages and load). Show only symbols for unknowns.
The speed of a 230 V shunt motor is to be reduced from 900 r.p.m to 600 r.p.m. The resistance of the armature circuit is 0.3 ohm. When the motor current is 30 A, speed is 900 r.p.m. If the current reduces to 20 A at lower speed, what arrangement should be made? Neglect any effect not included in the data given.
determine "A" through "G" for the DC motor on worksheet 5 when it is running at capacity and its specification are as follows rated input 125volt 16 amp armature resist. 0.3 ohms shunt field resist 50 ohm series field resist. .6 ohm rheostat resist. 12.5 ohm a- shunt field current b- armature current c- voltage drop of shunt field
A 320V shunt motor takes a total current of 80A and runs at 1000 rev/min. If the iron, friction and windage losses amount to 1.5 kW, the shunt field resistance is 40 ohm and the armature resistance is 0.2 ohm, determine the overall efficiency of the motor
A 240V shunt motor, running on no-load and at normal speed, takes an armature current of 2.4 A froma 240Vsupply. The resistance of the field circuit is 240Ω, and that of the armature is 0.25Ω. Calculatethe motor output power and efficiency when drawing a line current of 35 A from the supply
Urgent need in 5 mins pleasee At no-load, a 250-V series motor runs at 1000 rpm while taking 8A. The total armature and field resistance are respectively 0.5 22 and 0.25 2. Calculate the speed when loaded and taking 40 A.
A series motor runs at 800 rev/min when the voltage is 400V and the current is 25A. The armature resistance is 0.4 ohm and the series field resistance is 0.2 ohm. Determine the resistance to be connected in series to reduce the speed to 600 rev/min with the same current.
A 55 hp, 440 V, 400 rpm DC shunt motor draws 107 A when operating at rated conditions. The motor has an armature-circuit resistance of 100 mW and a total field-circuit resistance of 55 W. (vii) What is the motor no-load speed if the no load induced voltage is 440.85V? 390 rpm 395 rpm 400 rpm 405 rpm 410 rpm (viii) What would be the starting line current if the motor was started at full-voltage? 4107 A 4255 A 4392 A 4400 A 4408 A (ix) What is the motor full-voltage starting line current if a 1.9Ω starting resistor is connected in series with the armature? 212 A 220 A 228 A 6 A 6 A
The armature and field circuits of a 230-volt shunt motor have resistance of 0.31 and 115 ohms respectively. It takes 52 A when operating at a certain load. What is the counter emf?
A dc shunt motor operating at an armature terminal voltage of 125 V is observed to be operating at a speed of 1180 r/min. When the motor is operated unloaded at the same armature terminal voltage but with an additional resistance of 5Ω in series with the shunt field, the motor speed is observed to be 1250 r/min. i. Calculate the resistance of the series field. ii. Calculate the motor speed which will result if the series resistance is increased from 5Ω to 15Ω.
ASAP. PLEASE ANSWER THE QUESTIONS TO GET A LIKE a.In a dc shunt motor, the shunt field resistance is 100 ohms and the armature resistance is 0.01 ohm. It is supplied by a 250V source. If the shunt field is disconnected and is connected to a rheostat to control the speed of the dc machine, what should be the case if it is desired to increase the speed of the motor? -The resistance of the field rheostat should be decreased to be able to increase the speed of the motor -The resistance of the field rheostat should be increased to be able to increase the speed of the motor -The resistance of the field rheostat should not be changed to be able to increase the speed of the motor -The terminals of the field rheostat should be short circuited to be able to increase the speed of the motor b. In a dc shunt machine, reversing the terminals of the brushes will make the rotation of the shaft to rotate in other direction (e.g. from clockwise to counter-clockwise). Is it TRUE OR…
A 25 hp, 240 V, 1800 rpm dc shunt motor draws a full load line current of 89 A, and has an armature resistance of 0.05 Ω, and its field circuit resistance is 120Ω Calculate: to. The armature voltage that must be applied to the motor when it is running with no load at 1800 rpm. b. It powers them when the voltage calculated in a) produces an armature current of 4.2 A, at a speed of 1800 rpm.....