Abstract: One example includes a power relay system. The system includes a circuit breaker configured, when triggered, to provide an open circuit in a power line configured to conduct a current between a power grid point-of-interconnect (POI) and a power generator system. The system also includes a power controller configured to monitor the current and to generate a dynamic current threshold based on the current, the power controller being further configured to compare the current with the dynamic current threshold and to trigger the circuit breaker based on a difference of the current relative to the dynamic current threshold to set an arc flash incident energy level of the power generator system to less than or equal to a predetermined safety level.

Abstract: An apparatus and method is provided for measuring the caster angle of a steerable wheel assembly without contact with the vehicle. An image capture device, preferably a CCD type video camera or sensor, views a vehicle wheel mounting and steering assembly that is illuminated by a light source. Information from the captured image is transmitted to a computer based control, such as a computer or processor, that determines the angle of a preformed line or preselected physical features on the wheel assembly in the captured image, and determines the caster angle of the steering axis based on the fixed angular relationship of the line or physical features to the steering axis that is stored or accessed by the control. Preferably, the image capture device is mounted below the vehicle on a vehicle alignment machine that supports the vehicle.