Arguably in an extreme case the thin 'unprotected' wire is its own fuse - if there is enough current there, then any fault will blow to clear without troubling the upstream ADS.

That is fine, as a conscious design decision,where some thought is given to fixings and containment of the event and where all the burnt bits will end up... On a smaller scale, we are used to the idea that it is OK if an enclosed  piece of kit 'blows up' inside the box, so long as all the shrapnel is caught somewhere, and it does not get too hit and burn down the building.

However that sort of design is not something to sleepwalk into - if on its way down the bits of that melting thin wire can get somewhere that they  trigger an arc between the bus bars, or something of that sort of magnitude, then it is not really a safe 'self fusing' mechanism at all.

Mike

Arguably in an extreme case the thin 'unprotected' wire is its own fuse - if there is enough current there, then any fault will blow to clear without troubling the upstream ADS.

That is fine, as a conscious design decision,where some thought is given to fixings and containment of the event and where all the burnt bits will end up... On a smaller scale, we are used to the idea that it is OK if an enclosed  piece of kit 'blows up' inside the box, so long as all the shrapnel is caught somewhere, and it does not get too hit and burn down the building.

However that sort of design is not something to sleepwalk into - if on its way down the bits of that melting thin wire can get somewhere that they  trigger an arc between the bus bars, or something of that sort of magnitude, then it is not really a safe 'self fusing' mechanism at all.

Mike