Lighting device and luminaire

摘要

According to one embodiment, a_lighting device includes a lighting circuit and a control circuit. The lighting circuit includes an output end to which an illumination lamp is connected, and lights the illumination lamp by a direct-current power. The control circuit controls the lighting circuit so that power consumption caused by a contact resistance at a connection part between the illumination lamp and the output end of the lighting circuit during whole light lighting of the illumination lamp does not exceed a specified value set to 8 W or less.