117 1-800-447-2371 www.lutze.com LUTZE Technical Overview NFPA 79 Requirements for Appliance Wiring Material NFPA 79 is the Electrical Standard for Industrial Machinery in the USA. The NFPA 79 is a standard published by the National Fire Protection Agency, the same agency that publishes the National Electric Code (a.k.a. NEC or NFPA 70). NFPA 79 Chapter 12 “Conductors, Cables and Flexible Cords” and Chapter 13 “Wiring Practices” address the majority of cable related topics. A common concern in automation applications is the use of Appliance Wiring Material (AWM) per UL Subject 758 versus UL Listed cables such as UL Type TC-ER or many other listed types. The NFPA 79 has special provisions addressing safe wiring practices for industrial machinery, such as machine tools, described in article 12.9. This text was introduced with the 2012 edition, allowing the use of appliance wiring material (AWM) to be used with industrial machinery but is limited with special provisions. The use of such cable had been prohibited under the 2007 edition, and this restriction had caused a lot hardship for many machine manufacturers using AWM. This has been resolved since 2012 with the introduction of article 12.9 Special Cables and Conductors. NFPA 79 still mainly makes references to “Listed” cable. These cables carry a National Recognized Testing Laboratory (NRTL) listed logo such as the “UL Listed” logo. It should be noted that cables can have dual or multi ratings and carry both marks UL Recognized and UL Listed along with other marks. Permitted for all applications: Appliance Wiring Material is regulated by UL 758 and carries the UL Recognized logo. Since 2012 permitted for special applications: In order to use Appliance Wiring Material on industrial machinery and be compliant with NFPA 79, the cable must accommodate the provisions stated in article 12.9 “Special Cables and Conductors” of the NFPA 79 standard. It is sufficient to comply with one of the three conditions in section 12.9.2 instead of having to meet their requirements in combination. For example: 1. It is permissible to use AWM cable or conductors if part of a listed assembly has been identified for the intend use. 2. Or it is permissible to use AWM cable or conductors where the AWM has been identified for use with approved equipment and is used in accordance with the equipment manufacturer’s instructions. One example would be a servo drive system with a cable assembly made per the servo drive system manufacturer’s specification and installed per the manufacturer’s instructions. 3. Or it is permissible to use AWM cable or conductors where its construction meets all applicable requirements of Section 12.2 through Section 12.6 with some modifications. These modifications set requirements in terms of construction, flame resistance, insulation and voltage ratings as well as marking and print legends for clear identification. This will allow those types of AWM cables which are suitable for industrial use by their nature. However, it will control the misuse of AWM cables which do not meet industrial application requirements, e.g. voltage rating, insulation thickness, oil resistance, etc. All LUTZE AWM cables are designed for use in industrial environments and the AWM style and voltage rating is clearly marked on each cable jacket, therefore all LUTZE AWM cables can be used in applications governed by the NFPA 79 standard. For field installation it will still be safest to rely on cable that is UL Listed and verified for the intended use as required by the NEC (NFPA 70). UL Listed cable will make it easier to evaluate a machine in the field and will therefore remain a prominent choice for most machine builders in the USA. UL Listed cable will also eliminate the need for documentation that the use of AWM cable may require. Please contact your LUTZE representative with questions regarding our offering of UL Listed and UL Recognized cables to help you be compliant with the latest standards for industrial machinery. LUTZE offers many listed types, including MTW, TC-ER, PLTC and CM marks. Cables with these markings are considered listed types and are always permitted to be used in NFPA 79 compliant applications, as well as in applications per NEC. LUTZE Technical Overview NFPA 79 Requirements for Appliance Wiring Material NFPA 79 is the Electrical Standard for Industrial Machinery in the USA. The NFPA 79 is a standard published by the National Fire Protection Agency, the same agency that publishes the National Electric Code (a.k.a. NEC or NFPA 70). NFPA 79 Chapter 12 “Conductors, Cables and Flexible Cords” and Chapter 13 “Wiring Practices” address the majority of cable related topics. A common concern in automation applications is the use of Appliance Wiring Material (AWM) per UL Subject 758 versus UL Listed cables such as UL Type TC-ER or many other listed types. The NFPA 79 has special provisions addressing safe wiring practices for industrial machinery, such as machine tools, described in article 12.9. This text was introduced with the 2012 edition, allowing the use of appliance wiring material (AWM) to be used with industrial machinery but is limited with special provisions. The use of such cable had been prohibited under the 2007 edition, and this restriction had caused a lot hardship for many machine manufacturers using AWM. This has been resolved since 2012 with the introduction of article 12.9 Special Cables and Conductors. NFPA 79 still mainly makes references to “Listed” cable. These cables carry a National Recognized Testing Laboratory (NRTL) listed logo such as the “UL Listed” logo. It should be noted that cables can have dual or multi ratings and carry both marks UL Recognized and UL Listed along with other marks. Permitted for all applications: Appliance Wiring Material is regulated by UL 758 and carries the UL Recognized logo. Since 2012 permitted for special applications: In order to use Appliance Wiring Material on industrial machinery and be compliant with NFPA 79, the cable must accommodate the provisions stated in article 12.9 “Special Cables and Conductors” of the NFPA 79 standard. It is sufficient to comply with one of the three conditions in section 12.9.2 instead of having to meet their requirements in combination. For example: 1. It is permissible to use AWM cable or conductors if part of a listed assembly has been identified for the intend use. 2. Or it is permissible to use AWM cable or conductors where the AWM has been identified for use with approved equipment and is used in accordance with the equipment manufacturer’s instructions. One example would be a servo drive system with a cable assembly made per the servo drive system manufacturer’s specification and installed per the manufacturer’s instructions. 3. Or it is permissible to use AWM cable or conductors where its construction meets all applicable requirements of Section 12.2 through Section 12.6 with some modifications. These modifications set requirements in terms of construction, flame resistance, insulation and voltage ratings as well as marking and print legends for clear identification. This will allow those types of AWM cables which are suitable for industrial use by their nature. However, it will control the misuse of AWM cables which do not meet industrial application requirements, e.g. voltage rating, insulation thickness, oil resistance, etc. All LUTZE AWM cables are designed for use in industrial environments and the AWM style and voltage rating is clearly marked on each cable jacket, therefore all LUTZE AWM cables can be used in applications governed by the NFPA 79 standard. For field installation it will still be safest to rely on cable that is UL Listed and verified for the intended use as required by the NEC (NFPA 70). UL Listed cable will make it easier to evaluate a machine in the field and will therefore remain a prominent choice for most machine builders in the USA. UL Listed cable will also eliminate the need for documentation that the use of AWM cable may require. Please contact your LUTZE representative with questions regarding our offering of UL Listed and UL Recognized cables to help you be compliant with the latest standards for industrial machinery. LUTZE offers many listed types, including MTW, TC-ER, PLTC and CM marks. Cables with these markings are considered listed types and are always permitted to be used in NFPA 79 compliant applications, as well as in applications per NEC.
