energisation

Energisation is the process of supplying energy to a system or component so that it becomes operative or energetically active. In everyday usage it often refers to applying power to an electrical device or circuit, but the term can also describe the excitation of physical systems to higher energy states or the initiation of activity in a mechanical or chemical process.

In electrical engineering, energisation means connecting a device to its power source and establishing functioning conditions. For transformers, energisation refers to applying the operating voltage to windings to create the necessary magnetic field. In electric motors and generators, energisation establishes current flow and electromagnetic forces that start operation. Controlled energisation may use soft-start methods to limit inrush currents and reduce mechanical stress.

In power systems, energisation must be planned and coordinated to prevent faults; protective devices, synchronization, and sequential energisation of feeders are standard practices. In substations, equipment is tested for proper energisation under prescribed safety procedures to ensure reliable operation and to minimize disturbance to the wider network.

In medicine and biology, energisation may describe electrical stimulation of tissue or nerves, or the introduction of energy to initiate biological responses. In materials science, energisation can refer to magnetisation, polarisation, or other energy-state changes induced by fields or heat.

The term is derived from energy, with the suffix -isation or -ization, and is used in various technical fields to denote the act of imparting energy or activating a system. Usage varies by discipline, but the core idea remains the same: to bring something into an energy-bearing or active state.