To stop tracing sunbeams and turn a sunbeam tracing apparatus back to an original position without depending on a sensor for weather judgement by providing a plurality of sensors to detect sunbeams and the sensor for weather judgement in the inside of a condenser which can move horizontally and up and down directions and an outside part of the condenser and returning the condenser back to a starting position when the condenser excessively faces upward.

An automatic apparatus 1 for tracing sunbeams is provided with a condenser 2 consisting of a square box body and the whole face of an aperture part in the front face of the condenser 2 is closed by a Fresnel lens and an optical fiber 2b is connected with a condensing part 2a in the rear side of the condenser 2. A group of auxiliary sensors consisting of a sensor (d) for moving down the front face, a sensor (e) for moving down the condensing part which comprise hot transistors are installed in the condenser 2. The condensing part 2 is fixed in an axial body 12 installed in the upper part of a supporting pole 11 by a supporting member through an U-shaped fixing tool 13. A sensor apparatus 30 for weather determination which is to be installed near the supporting pole 11 has a sensor P for weather determination comprising hot transistors. A circuit part to drive the apparatus 1 consists of a control circuit part, a driving circuit part, etc.