Connection box for connection, electrical supply and overvoltage protection of meteorological sensors. Primary voltage: 230 V AC 50 Hz, secondary voltages: 12 V DC, 3 x 24 V DC, 4 x 24 V AC, overvoltage protection: varistor, protection class: IP65 according to DIN40050, including crossbar for attaching up to 2 meteorological sensors, including accessories for mounting the connection box on the crossbar, and the crossbar then on the mast with a diameter of 48 - 102 mm, preferably 50 mm.