Abstract: Alternating current (AC) photovoltaic (PV) modules are described. In one example, an AC PV module includes a PV panel (100) having a top surface, a bottom surface, and a plurality of sides extending between the top surface and the bottom surface, a frame (104) adjacent the plurality of sides of the PV panel, a junction box (204) attached to the bottom surface of the PV panel, an inverter (214) adjacent the bottom surface of the PV panel, and at least one direct current (DC) conductor (206) extending from the junction box to the inverter. The DC conductor is prevented from contacting the frame and/or other grounded metal.

Abstract: A pyranometer for measuring solar irradiance at a selected site comprises a light detector adapted to produce an output signal in response to incident solar radiation, a reversible motor having a curved shadowband attached to its output shaft, means for mounting the light detector and motor so that the shadowband is at a fixed distance from the light detector; and a motor controller that is adapted to periodically cause the motor to rotate the shadowband from one to the other of two limit positions, with the shadowband acting to momentarily shadow the light detector during its movement between its two limit positions. A datalogger stores and processes the light detector's signal output to provide a measure of total horizontal, direct normal and horizontal diffuse solar irradiance.

Abstract: A pyranometer for measuring solar irradiance at a selected site comprises a light detector adapted to produce an output signal in response to incident solar radiation, a reversible motor having a curved shadowband attached to its output shaft, means for mounting the light detector and motor so that the shadowband is at a fixed distance from the light detector; and a motor controller that is adapted to periodically cause the motor to rotate the shadowband from one to the other of two limit positions, with the shadowband acting to momentarily shadow the light detector during its movement between its two limit positions. A datalogger stores and processes the light detector's signal output to provide a measure of total horizontal, direct normal and horizontal diffuse solar irradiance.