Electrical Transformers and Rotating Machines
4th Edition
ISBN: 9781305494817
Author: Stephen L. Herman
Publisher: Cengage Learning
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Textbook Question
Chapter 9, Problem 1RQ
How does the National Electrical Code specify that the high leg of a four-wire delta connection be marked?
Expert Solution & Answer
To determine
The method specified by the National Electrical Code for the marking of the high leg of a four-wire delta connection.
Explanation of Solution
High delta leg is a type of electrical service connection which is also termed as wild leg, stinger leg, orange leg or red leg delta.
Whenever there is a need of power supply of both three phases and single phase power from a three phase transformer, high delta leg comes into use. The high delta leg voltage is
The specification for the marking of the high delta leg for a four wire delta connection is provided by National Electrical Code. As per this specification, the high delta leg must be connected to an orange wire or tagged at any point where a connection is made.
Thus, the National Electrical Code specifies that the high leg of a four-wire delta connection be marked by connecting it to an orange wire or by tagging it any point where a connection is made.
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2 A metal block of mass m = 10 kg is sliding along a frictionless surface with an initial speed
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Q1: Determine the length, angle of contact, and width of a 9.75 mm thick
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diameter of the driving pulley of the motor is 300 mm. The driven pulley runs at
300 r.p.m. and the distance between the centers of two pulleys is 3 meters. The
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Chapter 9 Solutions
Electrical Transformers and Rotating Machines
Ch. 9 - How does the National Electrical Code specify that...Ch. 9 - An open-delta three-phase transformer system has...Ch. 9 - If a single-phase load is connected across the two...Ch. 9 - Prob. 4RQCh. 9 - A three-phase transformer connection has a...Ch. 9 - A three-phase transformer bank has the secondary...Ch. 9 - A three-phase transformer bank has the primary and...Ch. 9 - Prob. 8RQ
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