NRZK-2000 series vacuum interrupter tester is used to calibrate the vacuum degree of the vacuum interrupter, with single-chip computer as the main control unit, the testing process is fully automated. The sampling design of the instrument uses the ion charge to do the calibration, instead of using the current peak value to do the calibration in the past. Thus, effectively inhibited the disturbances of transient power during the test, so the test is stable and reliable. Because the instrument adopts computer as the main control unit, the instrument can conveniently deduct the leakage current caused by the environmental factors.