Harmonic Currents in the Data Center: A Case Study

This document provides an overview of how problems related to harmonic neutral currents are solved by load diversity, with specific focus on Information Technology data center environments. Detailed measurements of an actual operating data center are presented.

The case study illustrates the way that load diversity mitigates harmonic current levels and lowers shared neutral current in multi-wire feeders and branch circuits.

Nonlinear loads cause harmonics to flow in the power lines. Harmonics are unwanted currents that are multiples of the fundamental line frequency (50 or 60 Hz). Excessive harmonic currents can overload wiring and transformers, creating heat and, in extreme cases, fire. In information technology power systems it is important to know when and how to address this issue. Recently, the problem has been mitigated by load diversity. This white paper extends the concepts related to modern IT data center loads presented in APC White Paper #26, “Hazards of Harmonics and Neutral Overloads”.

Click here or on the image to continue reading the full case study from American Power Conversion (APC).