Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
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Question
Chapter 21, Problem 12RQ
To determine
The size of the conductor required to supply all the motors.
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Students have asked these similar questions
A (21 HP, 3-Phase, 380 volts) motor with an efficiency of 95% is operating at a load
factor of 0.63. What is the input current (Amperes) when the power factor is 89%? (1
HP = 0.75 kW)
A 3 kVA motor operates from a 240 V
supply at 50 Hz and has a power
factor of 0.6. Determine the active
power
Select one:
1800 W
Non of the Answers
1900 W
2000 W
Question 2
Beli vifth
Slack side
Motor
(imprut)
Tight side
Beli thickpess\
Centre distance
Figure 2
Figure 2 shows an open flat belt drive connected to a motor and a pulley. The
motor transmits 20 kw to the connect pulley of 450 mm diameter and is rotating
at 850 r/min to a second pulley rotating at 400 r/min. The distance between
pulley centres is approximately 2 m. The belt is 6 mm thick and has a density of
970 kg/m. The maximum stress in the belt is not to exceed 2,7 MPa. The
coefficient of friction for both pulleys is 0,3.
Determine:
2.1. The diameter of the second pulley.
2.2. The length of the belt.
3.3. The width of the belt taking centrifugal tension into account.
Chapter 21 Solutions
Electrical Transformers and Rotating Machines
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Similar questions
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