MindTap for Herman's Understanding Motor Controls, 4th Edition [Instant Access], 2 terms
MindTap for Herman's Understanding Motor Controls, 4th Edition [Instant Access], 2 terms
4th Edition
ISBN: 9781337798754
Author: Herman; Stephen L.
Publisher: Cengage Learning US
bartleby

Concept explainers

Question
Book Icon
Chapter 35, Problem 1RQ
To determine

The electronic component generally used to change AC to DC voltage in large DC motor controllers.

Expert Solution & Answer
Check Mark

Explanation of Solution

The alternating current (AC) voltage is converted to direct current (DC) voltage in DC motors using two separate power supplies. By using two separate power supplies instead of resistors connected in series to the armature, it is smoother to control the speed of the DC motor.

One of the supplies is constant and connected to the shunt field and the other is a variable power supply connected to the armature.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Example 8: 900 Kg dry solid per hour is dried in a counter current continues dryer from 0.4 to 0.04 Kg H20/Kg wet solid moisture content. The wet solid enters the dryer at 25 °C and leaves at 55 °C. Fresh air at 25 °C and 0.01Kg vapor/Kg dry air is mixed with a part of the moist air leaving the dryer and heated to a temperature of 130 °C in a finned air heater and enters the dryer with 0.025 Kg/Kg alry air. Air leaving the dryer at 85 °C and have a humidity 0.055 Kg vaper/Kg dry air. At equilibrium the wet solid weight is 908 Kg solid per hour. *=0.0088 Calculate:- Heat loss from the dryer and the rate of fresh air. Take the specific heat of the solid and moisture are 980 and 4.18J/Kg.K respectively, A. =2500 KJ/Kg. Humid heat at 0.01 Kg vap/Kg dry=1.0238 KJ/Kg. "C. Humid heat at 0.055 Kg/Kg 1.1084 KJ/Kg. "C 2.8 1:41 م Ад O
Can you solve the question by finding initial angular acceleration of D then ueing it to calculate angular velocity of D.
: +0 usão ۲/۱ العنوان on Jon 14.23. A double-effect forward-feed evaporator is required to give a product consisting of 30 per cent crystals and a mother liquor containing 40 per cent by mass of dissolved solids. Heat transfer coefficients are 2.8 and 1.7 kW/m² K in the first and second effects respectively. Dry saturated steam is supplied at 375 kN/m² and the condenser operates at 13.5 kN/ m². (a) What area of heating surface is required in each effect assuming the effects are identical, if the feed rate is 0.6 kg/s of liquor, containing 20 per cent by mass of dissolved solids, and the feed temperature is 313 K? (b) What is the pressure above the boiling liquid in the first effect? The specific heat capacity may be taken as constant at 4.18 kJ/kg K. and the effects of boiling-point rise and of hydrostatic head may be neglected.
Knowledge Booster
Background pattern image
Mechanical Engineering
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Understanding Motor Controls
Mechanical Engineering
ISBN:9781337798686
Author:Stephen L. Herman
Publisher:Delmar Cengage Learning
Text book image
Electrical Transformers and Rotating Machines
Mechanical Engineering
ISBN:9781305494817
Author:Stephen L. Herman
Publisher:Cengage Learning
Text book image
Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning
Text book image
Automotive Technology: A Systems Approach (MindTa...
Mechanical Engineering
ISBN:9781133612315
Author:Jack Erjavec, Rob Thompson
Publisher:Cengage Learning