Understanding and Identifying UL Appliance Wiring Material (AWM) Styles
Appliance wiring material (AWM) is a large category of wire and cable that spans over different constructions. Underwriters Laboratory (UL) categorizes AWM as a Recognized Component used in Listed or Classified products. AWM is commonly used in a variety of applications such as general purpose wiring circuits, control circuits and internal wiring of appliances.
What Are UL Styles?
Underwriters Laboratory (UL) is a third-party testing laboratory that certifies and tests products. UL assigns a different style number for each approved AWM construction and creates a style page that lists a few specifications, such as gauge size range, insulation material, temperature rating and voltage rating.
Each style specifies the product’s general use as determined by UL’s evaluation of the product. Figure 1 is an example of a style page for UL Style 1015.
Over the years, many different wire constructions were developed and certified as UL AWM due to the high demand from various applications and industries. The large number of AWM styles leads to different interpretations of desired performance and evaluation methods.
UL Standard 758 Appliance Wiring Materials was developed to consolidate general requirements for AWM and standardize methods of evaluation. The standard includes performance requirements and methods for testing tensile strength and elongation, spark testing and dielectric voltage withstand. UL 758 also regulates marking and labeling of AWM products.
There are five sections of AWM wire. The different categorizations are based on the following criteria:
- Single conductor or multiconductor
- Thermoplastic or thermoset jacket
- Manufacturing method used to apply insulation, jacket or outer covering
UL has published a document that explains the different terminologies and associated numbers that are assigned to the different styles. For convenience, a reproduction of the table that addresses the style numbers and their use is listed below.
|1000–1999 and 10000– 19999||Single conductor, thermoplastic-insulated wire|
|2000–2999 and 20000– 29999||Multiconductor, thermoplastic-insulated and -jacketed wire
|3000–3999||Single conductor, thermosetting-insulated wire|
|4000–4999||Multiconductor, thermosetting-insulated and -jacketed wire|
|5000–5999||Single and multiple conductor specialty items|
Table 1: Appliance wiring material Style number designations
UL has a useful tool available on its iQ™ website (iq.ul.com/awm) that allows a user to access information about AWM wires.
A parametric search is one of the most helpful features when looking for a wire that meets specific application requirements. The search form allows the user to input the temperature, AWG size, material type as well as many other requirements, and it returns a list of styles that meet the input criteria. The site also allows users to search for companies that make a particular style, and it provides visibility to the style page itself.
According to UL iQ, there are over 7,000 different UL Styles. Some of the more common constructions are listed in Table 2 along with basic details about the style.
|Common Types||Size Range (AWG/ kcmil)||Insulation Type||Shield||Jacket Type||Voltage Rating (V)||Temperature Rating (° C)|
|2464||Not Specified||Not Specified||Optional||PVC||300||80|
|2919||Not Specified||Not Specified||Optional||PVC||300||80|
|4511||Not Specified||Not Specified||Optional||Silicone Rubber||600||200|
|4535||Not Specified||Not Specified||Optional||Silicone Rubber||600||150|
Table 2: Common UL Styles