Abstract:
Apparatus for selectively measuring voltage, resistance, and time duration f an event, each of which is associated with an electrical network, includes a device for providing a first train of digital pulses, the frequency of the pulse train being related to an analog voltage coupled thereto. The measuring apparatus also includes a clock for generating a second train of digital pulses of fixed frequency, and a constant current source to be coupled to a resistive element being measured by the apparatus. The apparatus further includes counters selectively receiving one of the digital pulse trains for counting the number of pulses received during a selected time period, and for providing a digital output in which the value of a quantity measured by the apparatus is encoded. A display coupled to the counter provides a visible numerical display of a measured value at the conclusion of the selected time period, and control means couples a plurality of binary control signals to the counters to determine the duration of each time period.