IEEE
IEEE C57.15-2017 is a published standard from the IEEE covering requirements, terminology and the test code for step-voltage regulators. These are the tap-changing devices that hold distribution voltage steady along a feeder, and the document gives manufacturers, utilities and test crews a shared basis for how they are rated and proven.
Editions cited: IEEE C57.15-2017
The standard is aimed at single-phase and three-phase step-voltage regulators of the type used on distribution lines and in substations. It defines the terms used for these devices, sets out the ratings and construction expectations for the finished product, and describes the tests used to demonstrate that a unit meets them, including electrical checks on the windings and insulation. Manufacturers use it to design and prove regulators, utilities cite it in purchase specifications, and field engineers and technicians use it as the reference behind routine work such as winding resistance and insulation checks during commissioning and maintenance. It stands apart from the general transformer standard because a regulator carries a load-tap mechanism and a control. This page describes the document in original words and does not reproduce it. For the requirements and tables, obtain a licensed copy of IEEE C57.15-2017 from the publisher.