Setup
Monitoring location : UPS for a desktop PCs sold in retail stores (1-phase 2-wire, 100V)
Problem & Analysis
Most low cost UPS used for general purposes output a square wave. However, most people assume that a sine wave is output. Here is a sample waveform output by a UPS.
- Low cost inverter type
- Commercial-type without a compensation function for the voltage distortion, etc.
Note that the voltage swell or dip occurs in switching if the UPS does not compensate for the period.
Source : Guidebook for Power Quality Measurement, HIOKI E.E. Corporation