Electrical Wiring Residential
18th Edition
ISBN: 9781285170954
Author: Ray C. Mullin, Phil Simmons
Publisher: Cengage Learning
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Chapter 27, Problem 15R
a.
To determine
Find the number of switches or circuit breakers permitted by a service disconnect.
b.
To determine
Find whether the overcurrent devices require being in one closure.
c.
To determine
Find the type of main disconnect provided in the residence.
d.
To determine
Find whether the city provides more than one service disconnect.
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Find Laplace transform and the corresponding ROC for
x(t) = e−3sin(2t) u(t)dt
Three similar coils, connected in star, take a total
power of 1.5 kW, at a power factor of 0.2, from a
three-phase, 400 V, 50 Hz supply. Calculate: (a) the
resistance and inductance of each coil; (b) the line
currents if one of the coils is short-circuited.
(a) Three 20 µF capacitors are star-connected across
a 400 V, 50 Hz, three-phase, three-wire supply.
Calculate the current in each line. (b) If one of the
capacitors is short-circuited, calculate the line cur
rents. (c) If one of the capacitors is open-circuited,
calculate: the line currents and the p.d. across each
of the other two capacitors.
ANS:
1.525 A; 2.64 A, 2.64 A, 4.57 A; 1.32 A, 1.32 A, 0;
210 V
Chapter 27 Solutions
Electrical Wiring Residential
Ch. 27 - Define the Service Point. ______________Ch. 27 - Define service-drop conductors.Ch. 27 - Prob. 3RCh. 27 - a. The service head must be located (above)...Ch. 27 - Prob. 5RCh. 27 - When a conduit is extended through a roof, must it...Ch. 27 - a. What size and type of conductors are installed...Ch. 27 - How and where is the grounding electrode conductor...Ch. 27 - What are the minimum distances or clearances for...Ch. 27 - What are the minimum size ungrounded conductors...
Ch. 27 - What is the minimum size copper grounding...Ch. 27 - What is the recommended height of a meter socket...Ch. 27 - Prob. 13RCh. 27 - Prob. 14RCh. 27 - Prob. 15RCh. 27 - Prob. 16RCh. 27 - Prob. 17RCh. 27 - Prob. 18RCh. 27 - Prob. 19RCh. 27 - Prob. 20RCh. 27 - Prob. 21RCh. 27 - Prob. 22RCh. 27 - Prob. 23RCh. 27 - Prob. 24RCh. 27 - Prob. 25RCh. 27 - Prob. 26RCh. 27 - Prob. 27RCh. 27 - Prob. 28RCh. 27 - Prob. 29RCh. 27 - Prob. 30RCh. 27 - Prob. 31RCh. 27 - Prob. 32RCh. 27 - Prob. 33RCh. 27 - Prob. 34RCh. 27 - Prob. 35RCh. 27 - Prob. 36RCh. 27 - Prob. 37RCh. 27 - Prob. 38RCh. 27 - Prob. 39RCh. 27 - Prob. 40RCh. 27 - Prob. 42RCh. 27 - Prob. 43RCh. 27 - Prob. 44RCh. 27 - Prob. 45RCh. 27 - Prob. 46RCh. 27 - Prob. 47RCh. 27 - Prob. 48R
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