Model 931A, with state-of-the-art PowerDSA^™ Digital Signal Analysis, make more measurements, more accurately, and at a lower price than ever before. Basic accuracy of 0.05 % of reading and 0.05° phase, harmonic analysis, and full three-phase capability are standard. Model 931A also incorporate full two way serial communication for use in power quality trend monitoring. The model expands usability by including transducer calibration and timer features.

Model 931A, featuring PowerDSA^™ Digital Signal Analysis, measures all of the basic quantities: true-rms voltage and current, frequency and phase angle, as well as power quantities such as watts (W), watthours (Wh), volt-amperes (VA), volt-ampere hours (VAh), volt-amperes reactive (VAR), volt-amperes reactive hours (VARh), and power factor (PF), all with 0.11 % basic accuracy.

Measure harmonics and view the results graphically on the high contrast 240x64 graphic display. The two channels are normalized to Channel 1 fundamental phase, so you can see, for example, the relationship between current waveform distortions and voltage phase.

Other key functions include a timer/counter for measuring relay operating times, elapsed test times, or for counting input rates and events.