400 amp fuse

[erict]

Originally Posted by scottyb

Yes, it blew the fuse? Didn't stop the fire from happening though did it? The reason I was asking is because I have seen controller failures, & motors fail and blow the controller, & I have seen batteries blown up .... but i have never seen one of those fuses blown.

I had asked that in the other thread because I wondered the same thing. If a controller failure didn't blow it in time then what will? Is it really a safety point

[sonicj]

controllers don't have to fail in a high current manner. you can start a fire with way less than 400A! a fuse isn't a 100% guarantee that things won't catch fire, however, it will prevent fires in certain scenarios.

obviously there was a high current fault at some point during the incident. had the fuse not been in place, the current would have continued to flow and undoubtedly caused much more damage.
-sj

[erict]

Originally Posted by sonicj

controllers don't have to fail in a high current manner. you can start a fire with way less than 400A! a fuse isn't a 100% guarantee that things won't catch fire, however, it will prevent fires in certain scenarios.

obviously there was a high current fault at some point during the incident. had the fuse not been in place, the current would have continued to flow and undoubtedly caused much more damage.
-sj

Makes sense

[delagem]

Cheapjeep2's thread also had me looking around! My stock setup has nothing, no fuse at all...

I went looking at the fuses, but I was also thinking of an emergency disconnect switch, as a 2nd means of shutting down, instead of wire cutters in the glove box.

I found this one at evdrives.com, but it's only rated for 250 amps.

http://www.evdrives.com/contactors_ED250.html



Won't it only being rated for 250 amps be a problem with my intended 400-500 amp controller and Plumquick motor?

Is there a higher emergency disconnect switch that anyone can recommend?

[scottyb]

Originally Posted by sonicj

controllers don't have to fail in a high current manner. you can start a fire with way less than 400A! a fuse isn't a 100% guarantee that things won't catch fire, however, it will prevent fires in certain scenarios.

obviously there was a high current fault at some point during the incident. had the fuse not been in place, the current would have continued to flow and undoubtedly caused much more damage.
-sj

How much more damage could it have caused to burn the end of the main lead off!?

[sonicj]

Originally Posted by scottyb

How much more damage could it have caused to burn the end of the main lead off!?

the main solenoid would likely weld shut and i imagine all of the batteries would likely have suffered damage (if not catch fire/explode) before any main leads burned completely though.
-sj

[sonicj]

Originally Posted by delagem

Won't it only being rated for 250 amps be a problem with my intended 400-500 amp controller and Plumquick motor?

Is there a higher emergency disconnect switch that anyone can recommend?

that switch is rated for 250A continuous. its peak rating is 1000A. to put this into perspective, most full size electric cars pull roughly 125A at cruising speed, while my CC with slightly modified motor pulls around 30A at WOT.

the kilovac contactor is capable of breaking 2000A one time. you can use it as your main contactor, but if you ever have to break a shorted pack it is supposed to be replaced. i believe the allbright sw200B is capable of breaking something similar; like 1800A. if you go that route, get the B model as it has the magnetic blowouts.

anderson SB350 connectors make ok emergency switches.

there are other ways to break high current, such as knife switches, etc. but thats all i know specifically.
-sj

[scottyb]

Originally Posted by sonicj

the main solenoid would likely weld shut and i imagine all of the batteries would likely have suffered damage (if not catch fire/explode) before any main leads burned completely though.
-sj

Is there any documentation of failed controllers welding solenoids and burning up the batteries? I would like to see this documentation or please tell us if this is all speculative ?


Millions of golf carts have been produced every year for decades which have no main battery fuse installed. Alltrax is the only speed control manufacture I know of who insists we use one. If this is a problem surely there would be more widespread use of the main fuse?

[Stevegrmich]

Originally Posted by scottyb

Is there any documentation of failed controllers welding solenoids and burning up the batteries? I would like to see this documentation or please tell us if this is all speculative ?


Millions of golf carts have been produced every year for decades which have no main battery fuse installed. Alltrax is the only speed control manufacture I know of who insists we use one. If this is a problem surely there would be more widespread use of the main fuse?

Hmm . . . design flaw that they are aware of and can't figure out . . ??

[scottyb]

More likely it is not an issue.

Come to think of it there is not a fuse on the Fords think or Gem car main battery either?