Abstract: If a main switch and a sub-switch are OFF and ON respectively, a comparator compares a source voltage value of the main switch to an output voltage value of a direct-current power source. In the same case, the comparator compares an end-to-end voltage value between a source and a drain of the main switch to a threshold value. A voltage value of the voltage applied to one end of the sub-switch is lower than the voltage value at the drain of the main switch. The output voltage value of the direct-current power source is lower than the voltage value. The threshold value is lower than the difference between the voltage value at the drain of the main switch and the voltage.

Abstract: An electric connection box provided with a circuit structure, a casing for accommodating the circuit structure therein, a plurality of bus bar terminals disposed on a cabling path crossing the casing in the horizontal direction and electrically connecting the circuit structure and an external connecter to each other, and a terminal support portion for supporting a horizontal portion crossing the casing in the horizontal direction in the plurality of bus bar terminals from below, wherein a partition wall for separating the adjacent horizontal portions from each other is provided on a face of the terminal support portion on the side supporting the horizontal portion.