Calculate proper fuse rating for automotive circuits considering wire gauge, load current, inrush, and NEC/SAE derating.
Input Parameters
Results
--
Recommended Fuse
A
--
Wire Ampacity
A
--
Inrush Current
A
--
Safety Margin
%
Note: Fuse must protect the wire, not just the load. Always fuse within 18 inches of the power source. ATO/ATC blade fuses are standard for modern vehicles.
Reference
Min Fuse = Continuous Load × 1.25
Fuse ≤ Wire Ampacity (protects wire)
Wire Ampacity derated for temp: A × (1 − 0.005×ΔT)
Inrush Current = Load × Inrush Multiplier
Standard fuse sizes per SAE J1284