25 kv Fuse on 15 kV line

[mivey]

But you've never had to place a 15kv rated cutout (and its link) on a 2.4kv system? Especially now that throttle fuses are no longer made (at least thats what I hear).

Nope.

 

[kwired]

That's true enough for some. They can fit a wide range of voltages. But if there is a catalog of voltages, they are specific for a reason. I just read that was important for current limiting fuses.

I'm sure there are variable depending on the fuse tech but I will have to read more.

Perhaps it matters due to the arc it has to create and how it extinguishes the arc. The length of the element, the element shape/size/configuration and difference for different voltages may play a role.

Maybe the arc length matters, maybe it is not that precise. I don't know.

Practically none before it is damaged. But when it starts to heat then melt it certainly rises.

But it could be the operating mechanism or protected system is sensitive somehow. Certainly seems to be the case for current limiting fuses anyway.​

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I will concede to it depends on what you are trying to do with the fuse. If you want current limiting features, coordination with other devices or narrow overload protection window, you do need more attention to details.​

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