Patent ID: 6268713
Filing Date: 2001-07-31
Classification: H02J

Abstract:
A method of testing safety circuits in battery charging systems, comprising:a) providing a power source with a return line for supplying or dissipating energy;b) providing a battery pack with one or more cells for storing or supplying energy;c) providing a fuse means connected in series between said power supply and said cell(s);d) providing a control switch whereby the switch, when closed, shorts either the power supply or cell(s) to ground through said fuse means;e) providing one or more power switches connected in series between said power supply and said cell(s);f) providing a series resistor for sensing current;g) providing an indicating means;h) providing a controller with memory which will, at either the onset of charging or the onset of discharging, verify the integrity of the protection circuit with these steps:1) measure the sense voltage across said sense resistor with said power switch closed;2) open said power switch;3) measure the voltage across said sense resistor again;whereby, when the sense voltage described is above a predetermined limit, the controller will record an error in said memory, notify the user through said indicating means, and when desired, close said control switch clearing said fuse and thus disabling said battery pack, andwhereby, when the sense voltage is below a predetermined limit, the controller will close said power switch.