When the zero of the circular scale does not coincide with the reference line when the fixed stud and the movable stud are brought into contact without applying any pressure, we state that there is a zero error.
Along with other metrological instruments like dial, vernier, and digital calipers, a micrometer—also referred to as a micrometer screw gauge—is a tool with a calibrated screw that is frequently used for precise measurement of components in mechanical engineering, machining, and most mechanical trades.
