Marine & Shipyards
Yards and vessels that specify 50 Hz, 60 Hz or 400 Hz during build-out and dock trials.
Shipyards inherit every frequency a vessel might be built for. The HPA copy names marine and avionics 400 Hz alongside commercial 50/60 Hz. The shore-power converter does the same at terminal scale.
Confirm insulation system (output is published as IT, neutral insulated) against the vessel’s earthing philosophy before the purchase order.