Connection system lug connector and circuit breaker system

Connection system, lug connector and circuit breaker system. One of the purposes of the utility model is to solve problems related to one or more problems existing in the prior art. According to one aspect of the present utility model, a connection system for connecting an alternative energy power supply line to a power company power supply line at a circuit breaker is provided. The connection system includes: a clasp, which can be electrically connected to the far end of the alternative energy power supply line, and the clasp has a hole through which the screw and screw pass through the hole in the clasp; a contact ring, which accommodates the contact ring around the screw; and a retaining ring, which can keep the contact ring against the clasp ring to make the screw and the clasp contact electrically with each other. One of the beneficial effects of the utility model is that the circuit breaker design can be used in existing circuit breaker boxes, and no new circuit breaker boxes need to be installed.