This meter was the first known AC meter to be patented, and like the Gardiner DC lamp-hour meter that preceded it, it only measured the time energy was supplied to the load. The meter was simply a clock operated by the alternating fields of the two coils. Lamp-hour meters were soon abandoned as customers started adding other electrical appliances and the need arose for meters that meters that measured energy, like Shallenberger's ampere-hour meter.

One of Jim B. Fuller's assistants was James J. Wood, who would soon become one of the key people at the Ft. Wayne Electric Co.