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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?
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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. |
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