As　far　as　low　voltage　AC　arc　is　concerned,　there　is　a　close　relationship　between　its　micro　state　and　macro　state.　Previous　studies　have　shown　that　there　is　a　correlation　between　the　characteristic　parameters　of　wavelet　energy　spectrum　of　arc　voltage　and　arc　burning　trend,　but　there　is　a　lack　of　theoretical　elaboration　and　verification.　In　this　paper,　from　the　perspective　of　spectral　analysis,　an　arc　generation　platform　with　spectral　measurement　function　is　built　to　realize　the　real-time　measurement　of　plasma　spectral　line　information　in　the　arc　gap.　And　the　electron　temperature　and　density　of　the　arc　are　calculated　by　the　Boltzmann　diagram　method　and　Stark　broadening　method,　and　their　data　trajectories　in　the　whole　arcing　process　are　recorded.　The　comparison　between　the　data　trajectory　and　the　wavelet　energy　time　spectrum　of　arc　voltage　shows　that　the　wavelet　energy　spectrum　eigenvalue　is　feasible　in　theory　as　the　macroscopic　characterization　parameter　of　arc　state.　Finally,　the　wavelet　energy　time　spectrum　of　the　new　intelligent　contactor　at　different　breaking　speeds　is　extracted　and　analyzed　to　verify　the　practicability　of　this　macro　characterization　parameters.　©　2022,　The　Author(s),　under　exclusive　license　to　Springer　Nature　Singapore　Pte　Ltd.