NFPA 731 Section 4.6.3.1 requires the installation of all wiring, cable, and equipment to be performed in accordance with NFPA 70 (NEC), Article 725 or Article 800, where applicable. Many circuits in a security system are “signal circuits” and NEC^® Article 725 must be followed.

One requirement in NEC^® 725.179(J) is that Class 2, 3, and Type PLTC Cables are not to be marked by the manufacturer with a voltage rating unless the cable has multiple listings and a voltage marking is a requirement for one or more of the listings.

If the cable doesn’t have multiple listings, and the cable is simply a Class 2, 3, or Type PLTC Cable, having the voltage rating on the cable may give the impression that the cable is suitable for Class 1 electric light and power applications.

Below is a sample of NFPA 731. For the complete section, see the actual NFPA 731 text at NFPA.ORG. Once there, click on the free access link to the latest edition of NFPA 731.

4.6.3 Wiring.

4.6.3.1 The installation of all wiring, cable, and equipment shall be performed in accordance with NFPA 70, Article 725 or Article 800, where applicable.

Below is a sample of the NEC^®. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the latest NEC^® edition of NFPA 70.

725.179 Listing and Marking of Class 2, Class 3, and Type PLTC Cables.

(J) Marking. Cables shall be marked in accordance with 310.120(A)(2), (A)(3), (A)(4), (A)(5), and Table 725.179(J). Voltage ratings shall not be marked on the cables.

Informational Note: Voltage markings on cables may be misinterpreted to suggest that the cables may be suitable for Class 1 electric light and power applications.

Exception: Voltage markings shall be permitted where the cable has multiple listings and a voltage marking is required for one or more of the listings.