Electric kettles with insulation function mostly have two heating tubes, one of which is individually controlled by an insulation switch, allowing users to control whether or not to insulate. The insulation power is generally below 50W, and it usually consumes no more than 0.1 kWh of electricity per hour.

The working principle of an electric kettle is that the steam generated during water boiling causes the bimetallic sheet of the steam temperature sensing element to deform, and this deformation drives the power switch to cut off power through the lever principle. Its power outage is non self resetting, so the kettle will not automatically reheat after the power outage.