In the context of a transformer, "HV" stands for High Voltage. It refers to the side of the transformer where the voltage is higher compared to the other side, which is typically called the Low Voltage (LV) side.
Transformers are electrical devices that transfer electrical energy from one circuit to another through electromagnetic induction. They can step up (increase) or step down (decrease) the voltage level depending on the configuration of their windings.
In a step-up transformer, the primary winding is connected to the low-voltage side, and the secondary winding is connected to the high-voltage side. This configuration is used to increase the voltage level, such as in power transmission applications where electricity is transmitted over long distances at high voltages to reduce energy losses.
Conversely, in a step-down transformer, the primary winding is connected to the high-voltage side, and the secondary winding is connected to the low-voltage side. This configuration is used to decrease the voltage level, such as in distribution transformers that reduce the voltage to levels suitable for use in homes and businesses.
Therefore, "HV" on a transformer indicates the side of the transformer where the voltage is higher, relative to the other side.