Patent ID: 8604695

Claim:
An emergency lighting system comprising: a power circuit carrying a utility voltage when a utility power grid is live, wherein a non-shielded electrical element of the power circuit produces an electromagnetic proximity field; a lighting circuit having electrical components including: a toroid-shaped coil, a battery, a rectification circuit, a light emitting diode (LED), a proximity transducer, and a not-and (NAND) logic gate; said coil having windings encircling the electrical element of the power circuit thereby producing an induced voltage in the lighting circuit when the utility voltage is present in the electrical element, and producing a charging current through the rectification circuit into the battery, the battery providing a first voltage level at a first input of the NAND gate; and the proximity transducer positioned for sensing the charging current and producing a second voltage level at a second input of the NAND gate; an output of the NAND gate interconnected with the LED for providing an illumination current thereto when the second voltage level at the NAND gate is absent.