1 Scope

1.1 These requirements cover small wind turbine systems (WT) and electrical subassemblies. With respect to this Standard, small WT are considered to be wind turbines where a user or service person cannot or is not intended to enter the turbine to operate it or perform maintenance. These units are intended for use in stand-alone (not grid-connected) or utility interactive applications. Utility-interactive, grid-tied WT are operated in parallel with an electric power system (EPS) to supply power to common loads.

1.2 The WT power, control and protection systems are evaluated only to the extent that they function within the manufacturer’s specified limits and response times. These control and protection functions are evaluated with respect to risk of electric shock and fire. It is intended that the electrical subassemblies that address power transfer control and protection functions evaluated per this document are to be coordinated with the mechanical and structural limitations specified in the Standard for the Small Wind Turbine, ACP 101-1-2021, or the applicable Standards for Wind Energy Generation Systems, the IEC 61400 standard series.

1.3 These requirements do not cover:

1. a) WT generating systems intended for hazardous locations;

2. b) Mechanical or structural integrity of the WT system or subassemblies;

3. c) Verification that the manufacturer-defined controls and protection limits maintain the WT system within its safe mechanical and structural limits; and

4. d) Mechanical loading of ladders, hoist supports, elevator mounting means, scaffolding, personnel tie offs, or other personnel load-bearing functional parts.

Summary of Topics

This new Second Edition of ANSI/UL 6142 dated December 11, 2025 includes multiple revisions including clarification, administrative edits, and universal upkeep.