240 V high-leg delta service

High-leg delta is an older service type, found mainly in rural areas. It was a cheap way to deliver 240 V three-phase plus 240 V or 120 V single-phase from one pole-mounted transformer. On the Solis S6-GC-30K-LV-US, the high side goes on the L2 or B phase. That phase is shown with the larger conductor at the AC input. The Solis S6-GC-30K-LV-US can connect to a 240 V high-leg delta service. First update it to HMI software C701 and DSP software 5906, then select the UL-240L grid standard. The Fronius Symo and Symo Advanced 10.0-3 and 12.0-3 208-240 models have a Hi-Leg Delta setup (HI1). A neutral conductor is required. Enphase IQ commercial microinverters cannot connect directly to a 240 V high-leg delta service. They need a transformer with a 208/120 V wye secondary, chosen by the installer according to the NEC and local code. Eaton makes 120/240 V high-leg delta surge protective devices with their own wiring diagram. Their protection modes include high leg to neutral, high leg to ground and high leg to line.

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• sentence 5: support check: partial - Passage gives 208/120 V wye secondary and installer-selected transformer per NEC/local code, but does not explicitly say direct connection is impossible or name IQ commercial microinverters. -->