Delmar's Standard Textbook Of Electricity
7th Edition
ISBN: 9781337900348
Author: Stephen L. Herman
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 32, Problem 1PA
You are working as a plant electrician. It is your job to install a 300-hp three-phase squirrel-cage induction motor. The supply voltage is 480 V. The power company has determined that the maximum amount of starting current that can be permitted by any motor in the plant is 3000 A. The motor nameplate is as follows:
| Phase: 3 | FLA: 352 |
| Volts: 480 | RPM: 1755 |
| Frame: XXX | Code: L |
Will it be possible to start this motor across the line, or will it be necessary to use a reduced-voltage starter to reduce starting current?
Expert Solution & Answer
Trending nowThis is a popular solution!
Students have asked these similar questions
(Practical Application)
#1 ) you are working as a plant electrician. It is your job to install a 300 hp three phase squirrel cage induction motor. The supply voltage is 480 V. The power company has determined that the maximum amount of starting current that can be permitted by any motor in the plant is 3000 A. The motor nameplate is as follows(photo) .
Will it be possible to start this motor across the line, or will it be necessary to use a reduced voltage starter to reduce starting current?
A 460VAC rated, 60 Hz, 125-Hp Three-phase induction type motor is to be connected for across-the-line starting. The nameplate indicates the motor’s maximum ampere rating, 160A. It has a NEMA code letter B. The ambient temp of the installation place is and TW copper will be used. Short-circuit protection device that will be used is Inverse Time Breaker.
Calculate the Motor Starter Size.
A 460VAC rated, 60 Hz, 125-Hp Three-phase induction type motor is to be connected for across-the-line starting. The nameplate indicates the motor’s maximum ampere rating, 160A. It has a NEMA code letter B. The ambient temp of the installation place is and TW copper will be used. Short-circuit protection device that will be used is Inverse Time Breaker.
Calculate the Thermal Overload Protection.
Chapter 32 Solutions
Delmar's Standard Textbook Of Electricity
Ch. 32 - What are the three basic types of three-phase...Ch. 32 - What is the principle of operation of all...Ch. 32 - What is synchronous speed?Ch. 32 - What two factors determine synchronous speed?Ch. 32 - Prob. 5RQCh. 32 - Name three factors that determine the torque...Ch. 32 - Is the synchronous motor an induction motor?Ch. 32 - Prob. 8RQCh. 32 - Why must a synchronous motor never be started when...Ch. 32 - Name three characteristics that make the...
Ch. 32 - What is the function of the field-discharge...Ch. 32 - Why can an induction motor never operate at...Ch. 32 - A squirrel-cage induction motor is operating at...Ch. 32 - Prob. 14RQCh. 32 - Prob. 15RQCh. 32 - Prob. 16RQCh. 32 - Name three factors that determine the amount of...Ch. 32 - Why will the rotor of a wound-rotor motor not turn...Ch. 32 - Why is the starting torque per A of starting...Ch. 32 - When is a synchronous motor a synchronous...Ch. 32 - What determines when a synchronous motor is at...Ch. 32 - How can a synchronous motor be made to have a...Ch. 32 - Is the excitation current of a synchronous motor...Ch. 32 - Prob. 24RQCh. 32 - Prob. 25RQCh. 32 - You are working as a plant electrician. It is your...Ch. 32 - You have been given the task of connecting a...Ch. 32 - You are an electrician working in an industrial...
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 460VAC rated, 60 Hz, 125-Hp Three-phase induction type motor is to be connected for across-the-line starting. The nameplate indicates the motor’s maximum ampere rating, 160A. It has a NEMA code letter B. The ambient temp of the installation place is and TW copper will be used. Short-circuit protection device that will be used is Inverse Time Breaker. Calculate the Conductor size.arrow_forwardA 460VAC rated, 60 Hz, 125-Hp Three-phase induction type motor is to be connected for across-the-line starting. The nameplate indicates the motor’s maximum ampere rating, 160A. It has a NEMA code letter B. The ambient temp of the installation place is and TW copper will be used. Short-circuit protection device that will be used is Inverse Time Breaker. Calculate the Branch Circuit Protection.arrow_forwardYour Answers may be presented through Discussions, Drawings/Figures/Diagrams, Reference to NEC/PEC and Computations What is the rated full-load current of a ¾-horsepower, 208-volt single-phase motorarrow_forward
- Your assumption is that you measure Insulation Resistance [IR] using MeggerTest on an Induction Motor that works on a line voltage of 440 Volts 50 Hz with a measurable test result of 0.5 M Ohm. Question : a. What about your conclusion, is the measurement value still in accordance with the provisions of the Class Recommendation?. b. What are your actions to be able to maintain and maintain the best IR value of electric motors ?arrow_forwardGiven a 25 hp, three-phase, 230-volt, squirrel cage induction motor. The ambient temperature of the place ofinstallation is 40°C. Use TW wiresarrow_forwardA 350-HP squirrel-cage induction motor is connected to a 480-volts three-phase feeder. The nameplate lists the following: HP 350, Service factor 1.10, Full-load amps 408, NEMA Code B. The conductors are to be copper with THWN insulation, and 600:5 current transformers are used to reduce the current supplied to the overload heaters. The motor circuit is protected with dual-element time delay fuses. Determine the conductor size, overload heater size using the chart shown in Figure 34-7, the NEMA and IEC starter sizes, and the fuse size for this installation.arrow_forward
- A 100-HP three-phase squirrel-cage induction motor is connected to 480 volts. The conductors supplying the motor are copper with THW2 insulation. The nameplate lists a full-load running current of 118 amperes, NEMA Code B, and a service factor of 1.00. Current transformers with a ratio of 200:5 are used to reduce the current supplied to the overload heaters. The motor is protected with dual-element time delay fuses. Determine the conductor size, overload heater size using the chart in Figure 34-7, NEMA and IEC starter sizes, and fuse size for this motor.arrow_forwardA 75 hp Induction-typed Squirrel cage motor, 575 volts rated two-phase motor. Calculate its phase current and nuetral current.arrow_forwardDEGREE: BS ELECTRICAL ENGINEERING COURSE: AC MACHINES Note: Please solve in this way. Given>Missing>Illustration>Solution>FinalAnswer. Please include symbols, units, formulas, step by step solution, please don't cut the solution. Thank you! (#19) The starting torque of a 7.5 HP, 440-volt 1,730 RPM induction motor is 2-1/2 times its rated full-load torque when the rated voltage is impressed. Calculate the starting torque when 230 volts is applied at the instant the motor is started. [ Answer: 15.55 lb-ft. ]arrow_forward
- The nameplate of a squirrel-cage induction motor has the following information: 25hp, 220V, 3-phase, 60 cycles, 830rpm, 64A per line. If the motor takes 20,800W when operating at full-load, calculate the efficiency.arrow_forwardA 50-horsepower, 460V, 60Hz, 3-phase induction motor has a Nameplate Rating of 60 amperes. The nameplate also shows a temperature rise of 30°C. Determine the Dual-element, time-delay fuses to be used for the motor’s branch circuit.arrow_forward11. A synchronous motor is being tested for efficiency. If an auxiliary motor is needed for the testprocedure, the method applied is theA. electrical input method.B. retardation method.C. calorimeter method.D. mechanical input method.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Delmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage Learning
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:9781337900348
Author:Stephen L. Herman
Publisher:Cengage Learning
How Electric Motors Work - 3 phase AC induction motors ac motor; Author: The Engineering Mindset;https://www.youtube.com/watch?v=59HBoIXzX_c;License: Standard Youtube License