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I have a circuit where I would like to replace standard 10A glass fuses with some resettable solution. I have looked into polyfuses:

https://lcsc.com/products/PTC-Resettable-Fuses_11042.html?q=poly%20fuse

It seems they don't produce these for larger amperages. Any suggestions? In size it needs to be around the same as the glass fuse or smaller.

Are these safe btw on the long run? Because let's say I have the device on a remote location if something gets shorted which plugged into it that should remain turned off. As I understand these polyfuses reset themselves I don't see that too safe as if it keeps turning back the device off which had the fault that might leads to fire and other issues.

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  • \$\begingroup\$ The 'polyfuse' will only reset itself after power to the device is removed and it's had a chance to cool down. \$\endgroup\$
    – brhans
    Commented May 3, 2021 at 14:41
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    \$\begingroup\$ A polyfuse is never likely to be a replacement for a regular fuse. It can be used alongside a regular fuse to prevent the regular fuse popping but, at the end of the day when the cows come home and the fat lady sings, it is the regular fuse that prevents a fire happening and makes your insurance company happy. \$\endgroup\$
    – Andy aka
    Commented May 3, 2021 at 14:45

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Polyfuses are inappropriate for short protection on mains applications. Take, for example, these Yageo parts:

enter image description here

They can only safely interrupt a few amperes of current, 10 at the most. Compare that with a 1/4" x 1.25" ABC type fuse.

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