3. Fuse Selection

Question.5

Tony is designing a 12V DC motor circuit.
The motor draws 8A during normal running.
He selects a 10A blade fuse for protection.
Will this fuse reliably work without nuisance blowing?

Yes — because 10A is higher than 8A
Yes — fuse rating only needs to exceed running current
Not Reliable — fuse may keep blowing on motor startup
No — fuse current rating needs to be 5x to 6x higher i.e. 40A to 48A

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