Patent ID: 8009055

Claim:
A high-voltage indication system, comprising: a voltage detector powered by a first power source and coupled to detect a voltage level of an energy storage device associated with an electric motor/generator, the voltage detector configured to: measure the voltage level of the energy storage device; compare the voltage level of the energy storage device to a threshold voltage value; and provide an indication signal when the voltage level of the energy storage device is greater than the threshold voltage value; and an indicator powered by a second power source independent from the voltage detector, the indicator configured to: detect the indication signal provided by the voltage detector; and provide one or more warning signals in response to the indication signal, an electrical isolation device coupled to the voltage detector and the indicator and configured to facilitate the transfer of the indication signal from the voltage detector to the indicator via an electrically-isolated path through the electrical isolation device; wherein the indicator includes a controller, electrically isolated from the voltage detector and configured to: generate a test signal simulating a high-voltage indicator signal generated by the voltage detector; monitor a response of the indicator to the generated test signal; and determine, based on the monitored response, whether the indicator is operating within a normal operating range.