Electrical leakage detection apparatus and system

An electrical leakage detection apparatus and system which inhibit failures caused by high-voltage noise invasion are provided. The electrical leakage detection apparatus according to embodiments includes an electric leakage diagnosis part and a relay. The electric leakage diagnosis part determines whether or not a direct-current leakage exists from a storage battery that provides and receives electricity to/from an alternating-current power system that includes an electrical leakage detector that detects an alternating-current leakage of alternating-current power supplied from a utility powersource. The relay disconnectably connects the secondary battery with the microcomputer. 本发明提供种能够抑制由于高电压噪声的侵入而导致的故障的产生的漏电探测装置以及漏电探测系统。实施方式涉及的漏电探测装置具备漏电诊断部和继电器。漏电诊断部进行是否从蓄电池漏出直流电力的漏电诊断，该蓄电池与包括对从商用电源供给的交流电力的漏电进行探测的漏电探测部在内的交流电力系统之间进行电力的授受。继电器能通断地连接在蓄电池与漏电诊断部之间。