A contact impedance test circuit for testing impedance between a first contact element and a second contact element comprising an AC signal source for applying an AC signal voltage to the first contact element, an AC contact voltage being emitted by the second contact element, an AC amplifier connected to the second contact element for amplifying the AC contact voltage from the second contact element, an amplified AC contact voltage being produced by the AC amplifier, and a phase angle voltmeter for detecting phase difference between the amplified AC contact voltage and the AC signal voltage at an instance of time, the AC. signal voltage being applied to a reference input of the phase angle voltmeter, the amplified AC contact voltage being applied to a signal input of the phase angle voltmeter.