ISA Interchange

Welcome to the official blog of the International Society of Automation (ISA).

This blog covers numerous topics on industrial automation such as operations & management, continuous & batch processing, connectivity, manufacturing & machine control, and Industry 4.0.

The material and information contained on this website is for general information purposes only. ISA blog posts may be authored by ISA staff and guest authors from the automation community. Views and opinions expressed by a guest author are solely their own, and do not necessarily represent those of ISA. Posts made by guest authors have been subject to peer review.

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AutoQuiz: What Type of Circuit Break Protection Should Be Used for Motor Control?

AutoQuiz is edited by Joel Don, ISA's social media community manager.

This automation industry quiz question comes from ISA's technical training course, Electrical Controls for the Control Systems Technician (TI23). This class focuses on electrical controls that are frequently overlooked in a formal training program. It is geared toward any level technician who wants a thorough review of electrical process concepts to reinforce their knowledge of basic electricity and develop skills required to install and maintain electrical control devices.

What type of circuit break protection should be used for motor control?

a) non-automatic circuit interrupter
b) thermal
c) magnetic
d) thermal and magnetic
e) none of the above

Here's the answer to this quiz question from ISA's course offering, Electrical Controls for the Control Systems Technician (TI23).

The symbols in the post image are used to represent thermal and magnetic overload protection for electric motors. These two devices when used in series helps prevent excessive damage due to overheating and short circuiting.

The correct answer is D.

About the Editor
Joel Don is the community manager for ISA and is an independent content marketing, social media and public relations consultant. Prior to his work in marketing and PR, Joel served as an editor for regional newspapers and national magazines throughout the U.S. He earned a master's degree from the Medill School at Northwestern University with a focus on science, engineering and biomedical marketing communications, and a bachelor of science degree from UC San Diego.

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Joel Don
Joel Don
Joel Don is an independent content marketing, social media and public relations consultant. Prior to his work in marketing and PR, Joel served as an editor for regional newspapers and national magazines throughout the U.S. He earned a master's degree from the Medill School at Northwestern University with a focus on science, engineering and biomedical marketing communications, and a bachelor of science degree from UC San Diego.

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