What Is a Floating Ground?

A floating ground is a type of electrical wiring solution that prevents an electrical circuit from returning electric current to the Earth. Electric devices using power cables that connect to wall outlets using only two prongs instead of three are designed with a floating ground.

The ground is the part of an electrical circuit that passes through some conductive route to the Earth. When an electrical device is built to isolate its interior analogue grounding points and distribute them to a single spot that is not connected to the Earth, the ground is considered a floating one.

There are numerous reasons why manufacturers may prefer to create a floating ground in an electric or electronic device;the most common of which is that it can protect the safety of a low-voltage power supply, such as those commonly used for smartphones and other consumer electronic devices. Since the power supplies that these devices rely on need to convert relatively high-voltage mains current to low-voltage electricity suitable for portable rechargeable batteries, the equipment manufacturer often chooses to guarantee the safety of the transformer by using a floating ground. This ensures that there is no electrical connection between the high-voltage power grid and the low-voltage electronic device, making it unlikely that the device will unexpectedly short-circuit when charging.