Quote:
Originally Posted by PAR_WIG1350
Given that the current draw of the loads(motors?) connected to the victors was not given, I assumed that it was not known.
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Moreover, the protection devices need to be sized to prevent an unsafe condition if there is a failure (i.e. a motor fails short, terminal block is shorted, etc). So, you can pick a wire gauge and size the fuse to it, then pick the load (but the load may not be able to draw all the current it wants or needs to). Or, you can pick a load, size the fuse to that, then select the wire gauge based on the fuse (so the load can draw all the current required). The former is often the case in FRC. The latter is the more real-world design methodology.
Really, your earlier statement about sizing the fuse to the wire encapsulates the broader idea that if a failure occurs the elements of the system need to mitigate the failure so that an unsafe condition is not reached. That safety concern is primarily thermal (not having a fire, preventing the insulation from melting, etc), but can also deal with other areas (like protecting the battery). In many cases the mitigation means a fuse, but there are other mechanisms (like foldback circuits) that can be used to prevent the unsafe condition due to too much current draw.
The simpliest for this application is probably the inline circuit breaker or fuse between the terminal block and battery that has been previously mentioned.