Author Topic: Smart Pie Battery Blowing Fuse Under Load  (Read 4619 times)

Offline Jmant

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Smart Pie Battery Blowing Fuse Under Load
« on: November 07, 2013, 07:54:50 AM »
Hi Forum,

I have Smart Pie powered by water bottle battery type 36v 8ah 250w. The system works very well under normal conditions however when I tow a child carrier loaded with luggage and into a strong wind with the throttle full on then I end up blowing the 20A fuse in the battery. Is there any way I can avoid blowing the fuse when under extreme load however I am restricted to 250W to comply with Australian regulations. 

Offline Sam.Vanratt

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Re: Smart Pie Battery Blowing Fuse Under Load
« Reply #1 on: November 17, 2013, 04:16:05 PM »
Hi
-did you reprogramm your MP3? Maybe it's not throttled by amperage? The Voltage should be 36 while Amp_Average should be 7-8A; max_Amp about half of allowed C's of your Battery pack (let's say 4C are allowed then I'd choose 2C; with 8Ah it woulkd be 16Amp max.
Cheers
Sam

Offline Andrew

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Re: Smart Pie Battery Blowing Fuse Under Load
« Reply #2 on: December 04, 2013, 09:42:07 AM »
try a 25A fuse ;D.  You may be pulling more amps than you think at peak pulling power on hills or when launching.  Can you be sure that your controller is set at 8amp max?   You may have to pull back the 'block time'  if you have this functionality on your controller. This allows the controller to exceed the max allowed amps for a certain amount of time.   i.e  it could be 0.5 seconds, it could be 5.     continous amps and max amps allowed can be very different.