Pilot lights, or power indicator lights as they are also known, can be used to indicate when a machine or industrial process has started or stopped. This could be done by changing the colour of illumination (red/green) or by momentary blinking or flashing. In most cases, they will be located on the machine or an easily accessible control panel to allow them to be operated easily. Pilot lights can even be used in hazardous areas dependent on the materials used to create them.
They are easily replaced and come in a number of shapes, colours and sizes (measured in mm) and are compatible with various voltages. Versions with LED lamps inside generally have a long lamp life and can last many thousands of hours. Most pilot lights come with the standard module itself, an interchangeable operator and a contact block.