Patent ID: 8373420
Filing Date: 2013-02-12
Classification: G01R,G08B

Abstract:
1. A ground fault detection system for detecting a ground fault in a network device, the ground fault detection system comprising: a power device configured to receive an input voltage referenced to a system ground and configured to supply an output voltage isolated from the input voltage; a first switch coupled to the power device to receive the output voltage; an energy storing element configured to be charged to at least a test charge from the output voltage when the first switch is in a first position and configured to be isolated from the power device when the first switch is in a second position; a second switch coupled to a port of the network device and configured to be selectively coupled to the energy storing device so that the port of the network device is not electrically connected to the energy storing element when the second switch is in a first position and electrically connected to the energy storing element when the second relay is in a second position; and a detection circuit configured to output an indication of the ground fault in the network device based on the test charge from the energy storing element when the second switch is in the second position; wherein the energy storing element is configured to: