DIGITAL METER FOR MEASURING ALTERNATING CURRENT

摘要

A digital meter (10) is designed for measuring alternating current and is formed of a metal rotary disk (20), a light-emitting element (30), a light-sensing element (40), a signal wire (50), and a signal conversion display (60). The metal rotary disk (20) is provided with a through hole (21) located at an appropriate position thereof. The light-emitting element (30) and the light-sensing element (40) are corresponding in location to each other such that they are located on a rotational path of the through hole (21). As the metal rotary disk (20) completes one revolution, the light-sensing element (40) receives a light signal which is transmitted via the signal wire (50) into the signal conversion display (60) by which the signal is converted (62) into a numerical value of power consumption. The numerical value of power consumption by a power user is thus attained by a terminal located in the power company without the use of a meter-person.