Patent ID: 6856162
Filing Date: 2005-02-15
Classification: G01R,H02S,Y02E

Abstract:
1. A combined AC/DC monitoring system for simultaneously monitoring an AC power supply and a DC power supply in a mobile unit, comprising: a transformer for electrically isolating the AC power supply from the combined AC/DC monitoring system and for providing an isolated, AC voltage signal to the combined AC/DC monitoring system; AC voltage monitor input terminals connected to the isolated AC signal for monitoring the isolated AC voltage signal; DC voltage monitor input terminals connected to the DC power supply for monitoring a DC voltage for the DC power supply; a DC shunt, said DC shunt having a first terminal connected to a positive, non-grounded terminal of the DC power supply and said DC shunt having a second terminal; a first DC current monitor input terminal and a second DC current monitor input terminal that are respectively connected to the first and to the second terminals of the DC shunt for measuring DC current from the DC power supply; an analog-to-digital converter ADC system having respective input terminals connected to the AC voltage monitor input terminals, the DC voltage monitor input terminals, and the DC current monitor input terminals, wherein the ADC provides respective digital output signals indicative of instantaneous sampled values of the isolated AC signal, the DC voltage, and the DC current; a microcontroller having input terminals for receiving respective digital output signals of the ADC, wherein said microcontroller digitally computes various respective computed variables from the respective digital output signals received from the ADC; a visual display system that receives signals representative of the computed variables from the microcontroller and that simultaneously visually displays a plurality of pre-selected ones of the respective computed variables; an alarm system that is selectively activated when a pre-selected computed variable is in a respective alarm condition that is outside (exceeds) a predetermined limit; wherein the microcontroller provides user menus displayed on the visual display system and wherein the microcontroller has keypress terminals for receiving respective user control signals from user-operated switches that are operated by a user in conjunction with the user menus to control operation of the microcontroller, the visual display system, and the alarm system.