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Looking into fuses for the battery pack. I'm running a 144 volt battery pack with NO potential to the chassis. I would have to have two points of contact with the 144 volt pack to have a problem. So, I still feel that I should have a 500 amp fuse in line with either the positive or negative cable to the controller in the event the controller has an issue, or internal short. or the controller goes into full throttle mode, uncommanded, or I have two points of contact to chassis for a full short.
Does anyone know how the production cars have built in protection from an uncommanded full throttle or runaway full power?
I am running an HPEV AC-51 motor with a Curtis 1239E controller.
 

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The fuse is typically placed mid pack from what I have seen.

I have no proof, but I expect uncommanded acceleration or run away would be stopped by opening a contactor. Not good for the life of the contactor to open under full load. But, that's one reason for the contactors.
 

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A fuse responds to excessive current. Full-power acceleration, intentionally commanded or not, isn't going to cause greater current to flow than the battery wiring can handle (which should be what determines the fuse rating) and the fuse rating needs to be higher than whatever current limit you set the controller for, so no fuse is going to do anything about uncommanded acceleration. If you want a panic button of some sort, it should turn off a contactor (relay).
 

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We're running something very similar (144v/AC51/1239e) and we run Ferraz Shawmut fuses inline with each of the four parallel battery strings. We bought them from EV West.
 

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The Leaf splits the pack with a safety disconnect plug that also includes the pack fuse. The original Leaf at least does not split the pack in exactly the middle but I think placing the fuse near the middle of the pack if possible, adds a modest increase in safety by reducing the maximum voltage available in any fault by a factor of ~2.
 
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