ALTERNATING-CURRENT TEST CIRCUIT

The present invention provides an alternating-current test circuit, comprising: a live wire input end and a null wire input end; a first diode and a second diode formed by Zener diodes of which the anodes are connected to each other; a first resistor and a second resistor; a rectification module connecting the live wire input end and the null wire input end; a power supply for supplying power; a current mirror module, the current values of a first output end and a second output end thereof having a fixed ratio; a unidirectional conduction module, used for enabling the current mirror module to conduct the first diode unidirectionally; and a current comparison module, comprising an oscillator, a timer, a current comparator, and a reference current source, and being used for comparing the current value of the second output end of the current mirror module with a reference current value. In the present invention, a power supply state of an alternating-current power supply is determined by measuring a resistance v