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.

All Posts

AutoQuiz: Standard Range for Pneumatically Transmitted Signals

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

Today's automation industry quiz question comes from the ISA Certified Control Systems Technician (CCST) program. Certified Control System Technicians calibrate, document, troubleshoot, and repair/replace instrumentation for systems that measure and control level, temperature, pressure, flow, and other process variables. Click this link for more information about the CCST program. This question comes from the Level I study guide, Domain 3, Troubleshooting. Level I represents a professional who has a five-year total of education, training, and/or experience.

 
The standard range for pneumatically transmitted signals is:

a) 3-15 psig
b) 5-20 psig
c) 1-10 psig
d) 4-02 psig
e) none of the above

Industry recognized early on that for the sake of ease and safety it would be better for an operator to monitor and control processes in a more convenient and protected place. The need for transmitting the process variable to that place settled on pneumatic transmission.

They used 3-15 pounds per square inch gauge (psig) as the range. The value of using three rather than zero is to detect failure of the instrument air supply. The measurement of 15 psig is for 100%, because it is well below nominal pressures for the air supply for diagnostic purposes.

Thousands of pneumatic instruments, controllers, and control valves remain in use even today, well into the digital signal transmission age.

The correct answer is A, 3-15 psig.

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.

Related Posts

Onward and Upward to 2025: Proud of a Great Year

As my year as president of the International Society of Automation (ISA) comes to a close, I wanted to ta...
Prabhu Soundarrajan Dec 20, 2024 10:00:00 AM

How Did Automation Professionals Benefit from ISA in 2024?

The International Society of Automation (ISA) is proud to be the professional home of thousands of member...
Kara Phelps Dec 17, 2024 9:30:00 AM

Ensuring RCM or DCS Redundancy and Its Security in a Complex Industrial Environment

In industrial automation, remote control managers (RCM) or distributed control systems (DCS) are critical...
Ashraf Sainudeen Dec 13, 2024 10:00:00 AM