Question 254Electricity/Electronics - QMED70% to pass
What is the name of the DC motor speed control method utilized as shown in figure "B" of the illustration? Illustration EL-0101

AI Explanation
The correct answer is C) Ward-Leonard.
The Ward-Leonard method is a speed control system for DC motors that uses a generator and a series-connected field rheostat to control the motor's field current and thereby its speed. This method was commonly used for DC motor speed control in the early to mid-20th century, including in various marine applications like those found on US Coast Guard vessels.
The other options are incorrect because they do not refer to a DC motor speed control method. Burmeister-Wain, Atlas-Copco, and Sperry-Rand are the names of companies or products, not the specific speed control technique depicted in the illustration.
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