Breaker for previewing line fault

The utility model discloses a breaker for previewing a line fault. The breaker comprises a closing locking member, a keyboard, a setting circuit, a microprocessor circuit, an inverse power detection circuit, a load line short circuit detection circuit and a drive circuit. The microprocessor circuit is connected with the closing locking member element through the driving circuit. The keyboard, the setting circuit, the inverse power detection circuit and the load line short circuit detection circuit are respectively connected with the microprocessor circuit. The inverse power detection circuit and the load line short circuit detection circuit are connected with a load line respectively. The microprocessor circuit detects whether inverse power exists on the load line through the inverse power detection circuit and detects whether a short circuit fault exists on the load line through the load line short circuit detection circuit. If detecting an inverse power fault or the short circuit fault, through the drive circuit, the closing locking member is controlled to carry out locking, and a closing operation is stopped. The utility model is suitable for various industrial and civil power distribution boxes.