Abstract: A back-up power system which can accommodate a standard electrical device that is operable from an alternating current power source when alternating current is available, but is operable by a direct-current to direct-current converter when alternating current is unavailable, the converter being powered by replaceable low voltage battery charged by the alternating current source, with the loss of alternating current being sensed to cause the disconnection of the alternating current source and connection to the low-voltage replaceable battery.

Abstract: A back-up power system for a portable table lamp which accommodates a standard replaceable compact fluorescent bulb that is illuminated from an AC main power source when AC house current is available and is illuminated by a DC to DC converter when AC house current is unavailable, the converter being powered by replaceable low voltage battery located in the base of the lamp and charged by the AC source, with the loss of AC house current being sensed to cause the disconnection of the AC house current source and connection to the low voltage replaceable battery.

Abstract: This is an emergency lighting system which permits at least one gas discharge lamp to be operated from an AC power source when AC current is present and from a battery when AC signal is not present. The circuit also provides the capability for turning the lamp on under other selected emergency conditions such as in response to an intruder detection, or in response to detection of smoke, heat, water, or some other emergency. In order to converse battery power in the DC mode, controls are also provided for turning off the light or reducing its output level in response to such control inputs as an ambient light detector or manually operated dimmer control. The system also provides a number of other improved features which cause the system to operate more efficiently than prior systems for performing the same function, thus providing greater energy to the lamp with the same source energy input, and reducing the heat generated by the system.

Abstract: A backup power system is provided for fluorescent lamps which energizes one of the lamps when normal A.C. mains power is not available. The circuit operates with a standard fluorescent fixture which contains two or more fluorescent lamps. When A.C. mains current is available, both lamps are operational so that the lighting fixture produces a maximum brightness. The A.C. mains current also trickle charges a low-voltage battery contained in the lighting fixture. When mains current is not available, the battery maintains only one of the lamps lighted. Consequently, although the lighting fixture produces a reduced output, the battery life is extended. In one embodiment both fluorescent lamps are powered directly from the AC line. When A.C. power is not available, a relay disconnects the A.C. line from both lamps and connects one lamp to a DC/AC inverter which is powered by the internal battery.