Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Shadow]

The contactor should open for gradual loads exceeding the rating for a period of time... if you have a dead short then the contactor does not have time to activate and the battery design 300A fuse will go.

You should not have two fuses one inline with the other, because you don't know which one will be tripped on a dead short. Fast acting breakers might or might not be effective, but they also can fuse themselves.

[mrwilsn]

The contactor should open for gradual loads exceeding the rating for a period of time... if you have a dead short then the contactor does not have time to activate and the battery design 300A fuse will go.

You should not have two fuses one inline with the other, because you don't know which one will be tripped on a dead short. Fast acting breakers might or might not be effective, but they also can fuse themselves.

The Zero design has two fuses inline with each other...the 300 amp fuse you mentioned in the battery and the 100 amp fuse in the aux charge port.  If you connect directly to the controller you are bypassing the 100 amp fuse therefore you should put a fuse or a breaker on your connection to the controller.  Or don't.  But the fuse is there to keep the wire from overheating and starting a fire, not to protect the battery or any of the bike electronics.  I'm not worried about gradual loads exceeding the 1C rate, in which case the contactor will open as you describe.  I'm worried about hot wire starting a fire because of a short.  In a dead short the one that will be blown will be the one with the lower rating.

[mrwilsn]

Also, that 300 amp fuse you referenced must be per brick otherwise an SR wouldn't  be able to pull 600 amps from the monolith.  So 300 amp x 4 = 1200 amps before you blow a fuse.  The wire you are using to connect to the controller and charge at 120 amps isn't rated for 1200 amps and it's going to get really hot before you blow a fuse in the battery.  Not to mention I would hate to blow that fuse in the battery cause it likely means that battery needs to be replaced as the fuse isn't easily accessible.  Which is why the onboard charger and aux charge port have their own 100 amp fuse (not each...they share the 100 amps but it's separate from the battery fuse).  If you connect to the controller you should use a fuse or a breaker....that's just my recommendation.  Do with it what you will.