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Old-fashioned fuse wire comes rated at 5, 15 and 30A. The equivalent MCBs (breakers) are rated 6, 16 and 32A.
Is there a reason for this difference?
Is there a reason for this difference?
An MCB has two functions: overcurrent heating a bimetallic strip and a solenoid that actuates with very fast rise times, as in a dead short.Not 100% sure but I thinks it's because fuses tollerate slightly higher short term currents. Eg they blow at 30A continuous but tollerate 32A for short periods.
Edit: Think that might be wrong because type B MCB actually trips at 3-5 times the rated current.