When the current is close to the fuse rating, the fuse will take some time to blow.
10 sec. , on a 15A fuse, would be approximately 30A

You should remove all current consumers from the wiring, put in a new fuse and then connect the consumers one by one, untill the fuse blows.

The tough method, is to put in a bigger fuse and wait for the smoke to show you where the problem lies
_________________
Poul
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