UL 231:2021 PDF Download

UL 231:2021 is a standard that covers power outlets and power outlet fittings for use in accordance with the National Electrical Code (NFPA 70). The standard applies to power outlets with or without integral mounting posts or pedestals.

The power outlets covered by this standard are suitable for a variety of applications, including outdoor locations such as farms and building sites where power is needed for portable or temporary equipment, supplying power to mobile homes or recreational vehicles, and providing shore power to boats.

A power outlet may contain various components, such as attachment plug receptacles, circuit breakers, fuseholders, fused switches, facilities for watt-hour meters, and provisions for field installed circuit breakers or switches and fuses.

Power outlet fittings covered by the standard are intended for factory or field assembly with or in conjunction with power outlets. These fittings may be panels or combination units incorporating receptacles, disconnecting means, overcurrent protection, or other equivalent devices. A separable mounting post or pedestal used for mounting power outlets is also considered a fitting.

The standard also mentions that power outlets may be designed for mounting on and connection to mounting posts or pedestals used with other types of distribution equipment. Some power outlets may have special features and markings to indicate their acceptability for use as service equipment.

Lastly, it specifies that power outlets with mounting posts are intended for mounting in concrete, while power outlets with mounting pedestals are intended for mounting on a concrete slab. However, mounting posts or pedestals should not be relied upon as the sole support for overhead wiring unless otherwise marked.