Why 16V polyfuse?

I am in the process of upgrading my printer to run on 24V, but I have a question regarding the 16V, 11A polyfuse. Why is it rated at 16V? I can't see there ever being anything near 16V dropping across the fuse as it should be conducting with very low resistance. Using the datasheet specifications, when conducting 11A of current with a maximum resistance of 0.0089 ohms, that's only 0.09V dropped by the fuse. Using a 24V bed wouldn't draw that much current anyway. I understand that I need to change it, especially having read the reports on here about them catching fire and I will remove it and use a real fuse in it's place. I would just like to understand why.

Thanks

I think that the problem is when you have a short: Then you will have the full 24V over the fuse, and that's when it gets dangerous and the fuse can catch fire before it traps.

Quote
enif
I think that the problem is when you have a short: Then you will have the full 24V over the fuse, and that's when it gets dangerous and the fuse can catch fire before it traps.

Exactly.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Cheers, I am still learning this stuff so I am very grateful for your replies. I need to start thinking about what happens in fail states