Marine Electrical Load Calculator
Calculate total DC electrical load and sizing requirements per ABYC E-11
Navigation & Safety Equipment
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Comfort & Convenience
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Custom Equipment
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Daily Load Summary
Total Daily Consumption
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Total Daily Amp-Hours
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Peak Load (all on)
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Peak Current Draw
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Average Hourly Draw
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System Sizing Recommendations
House Battery Bank (min)
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House Battery Bank (recommended)
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Alternator Output (min)
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Solar Panel (daylight charging)
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Main Fuse/Breaker Size
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Load Breakdown
| Equipment | Watts | Hours | Wh/Day |
|---|---|---|---|
| Click Calculate to see breakdown | |||
About Marine Electrical Load Calculations
ABYC E-11 Standard: The American Boat and Yacht Council E-11 standard provides guidelines for DC electrical systems on boats. Battery sizing should allow for 50% depth of discharge for lead-acid or 80% for lithium.
Battery Sizing: Minimum bank size = Daily Ah / 0.5 (lead-acid) or Daily Ah / 0.8 (lithium). Recommended adds 30% safety margin for aging and temperature effects.
Charging: Alternator should provide at least 25% of battery capacity as output. Solar should cover daily consumption assuming 4-5 peak sun hours.
Safety: Main fuse should be sized at 125% of maximum expected load, but never exceed cable ampacity ratings.