Should UPS Output be treated as a Separately Derived System per NEC?

[Anonymous user]

Installing a 15 kVA UPS, 208 V, 3-phase input; 208Y/120, 3-phase, 4-wire wye out (SUVTR20KF4B5S plus Battery Cabinets). The manual does not specifically state, but wouldn't NEC consider the UPS Output a "Separately Derived System" and be treated much like the secondary of a new 15 kVA xfmr? Specifically, shouldn't the new UPS installation require an additional Grounding Electrode Conductor (GEC)? Note that I'm NOT asking about an Equipment Grounding Conductor (which would be typically be installed with the supply & load conductors). I'm asking about a "Grounding Electrode Conductor" similar to that installed between a transformer neutral to building steel and/or water piping.