About trouble light
A trouble light, also known as a rough service light or inspection lamp, is a special lamp used to illuminate obscure places and able to handle moderate abuse. The light bulb is housed in a protective cage and a handle that are molded to form a single unit. It has a long power line for distant reaching; doubling as an extension cord, the power cord often has an electrical outlet at the end of it.
Trouble lights are usually powered by AC wall current, but some are powered by a 12-volt source, such as a car battery. The bulb of the trouble light typically has a heavy filament to withstand dropping. It is also referred to as a drop light.
Trouble lights are intended to be used with rough service bulbs, a form of incandescent light bulbs which have lamps designed with as many as five support wires holding the filament, designated as "rough service". Lower voltage bulbs such as those intended to function with 12 volt power supplies also have a higher lumen output per watt of power consumption. Fluorescent lamps and light-emitting diodes are also used to make trouble lights.
Trouble lights intended for use in hazardous areas such as in petrochemical plants will have features designed to prevent ignition of flammable gas around the lamp, such as heavy sealed lamp enclosures and guards to protect lamps from breaking.