The EVO 1500-1400 and EVO 1500-1400 FLO are the same high-voltage power supply with one key difference: output grounding. The standard EVO 1500-1400 has a ground-referenced output, meaning one terminal is tied to earth ground. The FLO (floating output) version has an isolated output where neither terminal is referenced to ground. Floating output is required when your load is not ground-referenced — for example, the Berkeley Nucleonics PVX-2506 high-voltage pulser requires a floating output power supply. If you are unsure whether your application needs floating output, contact Berkeley Nucleonics engineering for guidance.