Patent · US Expired

Open battery bank detector circuit

US4968943A · kind A · utility

7Cited by
7References
7Claims
0Family size

Inventor

Key dates

Filing dateApr 28, 1989
Grant dateNov 6, 1990
Priority date
Expiry dateApr 28, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R31/52
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The non-intrusive open battery bank detector circuit senses an alternating current component of the DC trickle charge carried by one of a pair of cables connected between the battery charger and the bank of batteries. The detector circuit includes a sensor that is disposed adjacent, but not physically around or electrically connected to, one of the cables. The sensor detects magnetic fields established around the cable. The output of the sensor is connected to a low-pass filter which passes signals consisting primarily of 60 and 120 hertz components. A pre-amplifier amplifies the passed signals. A ripple filter smoothes the pre-amplified signals and a comparator determines whether the smoothed signal is greater than a reference signal thereby signifying the presence of a DC trickle charge on the cable next to the sensor. A transistor switch has its control input connected to the output of the comparator and is triggered on when the output of the comparator is high. The output of the transistor switch is connected to a control coil of a relay switch such that when the transistor is turned on, current passes through the relay coil and closes a normally open contact in the relay. When…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.