... ,600 V CAT2) Power measurement of 3-phase 3-wire, 3-phase 4-wire, single-phase mode 3) V, A, W, VA, ... power value and five power parameters of each phase in 3-phase measurement mode respectively 6) Autorange and TRMS display ... tested signal be power supply for the clamp at one time, the instrument can measurement for long time 9 ... for voltage, current: 45 Hz ~ 65 Hz Three Phase Digital Power Clamp Meter