Oliver Blackburn Shallenberger (May 7, 1860 – January 23, 1898) was an American electrical engineer and inventor. He is associated with electrical inventions related to alternating current. He is most noted for inventing the first successful alternating current (AC) electrical meter, the forerunner of the modern electric meter. This was critical to general acceptance of AC power.[1]
...the first successful AC ampere-hour meter in 1888. This meter measures the flow of electric current through a circuit. Early meters like this helped companies that supplied electricity to customers monitor usage and charge appropriate rates. Shallenberger's meter also paved the way for the acceptance of AC power distribution.