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Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

load tap changer (LTC)
a tapped transformer winding combined with mechanically or electronically switched taps that can be changed under load conditions. The load tap changer is used to automatically regulate the output of a transformer secondary as load and source conditions vary.
no load tap changer
device that provides for changing the tap position on a tapped transformer when the transformer is de-energized. Different taps provide a different turns ratio for the transformer.
tap changer
a device to change the tap setting on a transformer coil, allowing voltage control. See also tap, tap changing under load.