Re: Want to move to all 208V for server racks

btw, one thing I do not recall seeing on this thread is that 208v avoids one of the common problems with 120v, which is the third harmonic issue. With the cheaper switching power supplies, one will often see significant 3rd harmonics in the waveforms(*). The 3rd harmonic, across a 3 phase circuit, are additive on the neutral. In worst case, your (common) neutral current may exceed the line currents. Proper engineering for significant 120v distribution in new DC construction often requires double sized neutrals to mitigate against this. Using 208v mitigates this particular issue. Gary (*) There are also other harmonics, but for this discussion, 3rd is what matters.