Lucent Technologies Inc.

Franklin F Makan

Vijayan J Thottuvelil

Robert J Kakalec

Andrew K Hatate

For use with a grounded power plant, capable of powering a load, having a power supply and a power distribution system, a protective circuit, including a voltage clamping device, coupled between a return conductor of the power distribution system and the ground, that attenuates voltage transients present in the return conductor of the power distribution system thereby preventing the voltage transients from damaging the load.

Protective circuit for a grounded power plant

In a backup power system capable of deriving power from alternate AC primary and DC backup power sources to provide continuous AC power to an AC load and including an inverter/switch module having DC and AC inputs and an AC output, a maintenance bypass switch for, and method of decoupling the AC primary and DC backup power sources from the backup power module to allow maintenance to be performed thereon. The maintenance bypass switch includes a selector switch configured to function in alternate normal, standby bypass and maintenance bypass modes of operation, wherein: (a) in transitioning from the normal mode to the standby bypass mode, the selector switch decouples an inverter in the inverter/switch module from the DC backup power source, (b) in transitioning from the standby bypass mode to the maintenance bypass mode, the selector switch further couples the AC primary power source directly to the AC load and (c) in the maintenance bypass mode, the selector switch decouples the AC primary power source from the AC input of the inverter/switch module, the DC backup power source from the DC input of the inverter/switch module and the AC output of the inverter/switch module to the AC load, the maintenance bypass switch providing the continuous AC power to the AC load throughout the transitioning.

Growing community of inventors

Rockwall, TX, United States of America

Franklin F Makan