Apparatus for generating a self-check leakage current

An apparatus for generating a self-check leakage current, comprising:

• a mechanical switch which is configured to simultaneously switch on and off a phase line and a neutral line,
• a neutral line solid-state switch arranged on the neutral line and located between the mechanical switch and a current transformer,
• the current transformer arranged upstream of the neutral line solid-state switch, and the phase line and the neutral line pass through the current transformer,
• a bypass unit comprising a bypass switch and a bypass resistor connected in series, one end of the bypass unit is connected to the upstream of the current transformer on the phase line, and the other end is connected between the mechanical switch and the neutral line solid-state switch on the neutral line, and
• a control unit which is configured to control the switching on and off of the neutral line solid-state switch and the bypass switch, and to receive a current value detected by the current transformer,
• wherein the self-check leakage current is generated when the neutral line solid-state switch and the bypass switch are switched on.

A circuit comprising:

• a mechanical switch comprising a first mechanical switch input and a second mechanical switch input,
• a phase line solid-state switch comprising a first input and a first output, the first input coupled to a first wire corresponding to a phase line, the first output coupled to the first mechanical switch input such that the phase line solid-state switch is upstream to the mechanical switch,
• a bypass switch comprising a first end and a second end, the first end coupled to a second wire corresponding to a neutral line, the second end coupled to at least one of the first output or the first mechanical switch input, and
• a control unit configured to control the phase line solid-state switch, the bypass switch, and the mechanical switch to generate a leakage current.