How long can the EcoFlow DELTA Pro Ultra run a CPAP machine?
16.3 dayswell beyond what you asked for
Formula: (6.1kWh × 0.85 inverter efficiency) ÷ 0.32 kWh/day = 16.3 days. At continuous 40 W draw (no duty cycle), about 5.4 days.
What if you add a battery? The + Extra Battery config jumps to 12.3kWh — roughly 32.6 days on a CPAP machine.
Appliance
CPAP machine · 40 W / 60 W surge
Battery (base)
6.1kWh · 7.2kW / 10.8kW surge
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Runtime Quick-Check
Runtime Quick-Check
Pick a battery and an appliance — see days of runtime after the 0.85 inverter derate.
16.3 days
Formula: (6144 Wh × 0.85) ÷ 0.32 kWh/day = 16.3 days. Continuous draw ≈ 5.4 days at full load.
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