A FORUM FOR FIRE PROTECTION QUESTIONS & PE EXAM PROBLEMS | SUBSCRIBE NOW
|
Is there an easy way to recognize the fire alarm circuit class: A, B, C, D, E, N, or X? That is, is there a way to determine the class, just by looking at the diagram or plan of the circuit?
Note: This is a question submitted anonymously to us (you can submit any question here) as part of our new Daily Discussion series. Discuss this question here.
3 Comments
Ben H
8/21/2017 08:25:46 am
Class A vs. Class B wiring is fairly straightforward when looking at plans - Class A circuits will loop back forming a redundant path, whereas Class B circuits will not. However, I'm not sure about the others and would be interested in this as well. I don't believe the circuit designation can be picked off drawings only based on the plans or diagram; as far as I'm able to tell the only help the plan or riser diagram would offer is whether there is a redundant path, (such as for Class A, N, and X designations as in NFPA 72-2016 Section 12.3).
Mike Richiutti
8/22/2017 09:03:09 am
As the previous answer stated the presence or absence of a return loop shows the difference between class A & B. The other classes of wire are more dependent on their performance requirements, and more information would be needed to identify the circuit type or class. For example, class A and X are pretty similar, only they perform different under certain circumstances. Leave a Reply. |
Free SignupSubscribe and learn something new each day:
CommunityThank You to Our Top September Contributors!
Your PostThe ToolkitSprinkler Designer or Engineer?
Get all of our tools, including the Sprinkler Database, Friction Loss Calculator, Fire Pump Analyzer and more: 
Filters
All
Archives
November 2019
Daily
Daily discussion questions are open-ended questions posed by members for the benefit of sharing expertise and learning from other perspectives. Join as a member here.
Exam Prep
2019 PE Prep Guide
(Available Now!) 
PE Prep Series
(Available Now!) Current Leaderboard
(Click to enlarge) 
PE Problems
Visit July-October for daily Fire Protection PE Exam sample questions.
Solutions are posted the day after posting. Comment with your solutions, questions or clarifications. Please note that questions posted are unofficial and in accordance with NCEES rules are intended to be similar to actual exam questions, not actual exam questions themselves. |
RSS Feed
