Which NFPA 70 article governs Class 1, Class 2, and Class 3 Remote Control, Signaling, and Power Limited Circuits?

Which NFPA 70 article governs Class 1, Class 2, and Class 3 Remote Control, Signaling, and Power Limited Circuits?

• A. Article 725
• B. Article 720
• C. Article 727
• D. Article 760

Answer: (A)

The key idea here is that NFPA 70 organizes wiring rules by specific types of circuits, so there’s a dedicated article for remote-control, signaling, and power-limited circuits. The article that names Class 1, Class 2, and Class 3 Remote-Control, Signaling, and Power-Limited Circuits sets the requirements for how these low-energy control paths are installed, including wiring methods, conductor sizing, overcurrent protection, and how they must be kept separate from higher-energy circuits. This keeps control and signaling systems safe and reliable while limiting energy and potential hazards. Other articles cover different topics. One focuses on general power distribution or standby systems, another covers instrumentation and control wiring outside this specific Class 1/2/3 scope, and another deals with fire alarm signaling, which is a distinct specialized area. So the article that governs Class 1, 2, and 3 remote-control, signaling, and power-limited circuits is the one specifically titled for those circuits.

The key idea here is that NFPA 70 organizes wiring rules by specific types of circuits, so there’s a dedicated article for remote-control, signaling, and power-limited circuits. The article that names Class 1, Class 2, and Class 3 Remote-Control, Signaling, and Power-Limited Circuits sets the requirements for how these low-energy control paths are installed, including wiring methods, conductor sizing, overcurrent protection, and how they must be kept separate from higher-energy circuits. This keeps control and signaling systems safe and reliable while limiting energy and potential hazards.

Other articles cover different topics. One focuses on general power distribution or standby systems, another covers instrumentation and control wiring outside this specific Class 1/2/3 scope, and another deals with fire alarm signaling, which is a distinct specialized area. So the article that governs Class 1, 2, and 3 remote-control, signaling, and power-limited circuits is the one specifically titled for those circuits.