... SF-1050W Single-phase Meter Calibrator is an electronic intelligent single-phase AC/DC meter calibrator designed according to related national ... can calibrate and test class below 1.0 single phase AC/DC ammeter, voltmeter, milli-ammeter, milli-voltmeter, frequency meter. ... to avoid damaging the equipment.3 Main Technique Parameter3.1. AC voltage provides 11 steps/positions: 15V, 30V, 75V, 100V, ...