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.
Which of the statements listed is correct for the measurement of resistance?
a) resistance is measured in parallel with the circuit de-energized
b) resistance is measured in series with the circuit energized
c) resistance is measured in parallel with the circuit de-energized and the device being measured isolated
d) resistance may be measured in series or parallel as long as the circuit is energized
e) none of the above
Click Here to Reveal the Answer
Here’s the answer to this quiz from ISA’s course offering, Electrical Controls for the Control Systems Technician (TI23).
Circuits should be de-energized. Place the mode switch in “OHMS”, short the meter leads together, press the “REL” button and connect the leads as shown in the diagram. Absolutely no circuit path for the measured component.
The correct answer is C.
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.