Discharge via BMS or Bypass BMS? [SRO]

The voltage rating doesn’t affect when it blows.

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It does. Read about it. But I wasn’t referring only to the voltage rating only. I just don’t want to trust a fuse rating from a chinese company which even don’t provide a fusing chart. What if the 80A fuse is in fact only a 35A fuse because if no quality control? :thinking::+1:

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I completely agree with the possible lack of quality control, but I have looked into fuse voltage ratings before.

https://www.quora.com/Why-do-fuses-have-voltage-rating

It’ll blow based on the current, and the voltage across the fuse will usually be a mere fraction of the voltage rating. The rating is important for making sure the fuse doesn’t arc after blowing.

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this is the reason i run my bestech HCX-D223V1. it has an eswitch which makes life a whole lot easier, has individual cell voltage discharge cutoff, up to 20a charging, 80a discharge and purely piece of mind. also it only charges to 4.15v i believe so you have headway up to 4.25v where the overvoltage cutoff is

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Stating it just like this, without mentioning the arcing hazard, is a big omission! Also AC vs DC voltage rating matters for similar reasons - AC tends to self extinguish the arc because it crosses zero volts.

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Ah perhaps you’re right, was focused on the other aspects.

@pjotr47
Is this a PC app? or iPhone app?
There is no “delay” in my android app(V2.1.1024). :cry:

That is the iOS app. But on the pc app you can set it also

I got it. Thanks!

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I have a 40Ah pack and bypassed discharge and set max discharge current to 70A with my Focbox Unity.

@pjotr47 do you fuse the main positive or Negative? Thx

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Most off the time the postive. But it is not that most important.

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It is not safe. When some cell groups reach 4.2V and others not, BMS will stop current from the charger and will balance cells. When you charge through bypass BMS can not stop it.

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This thread is the top result for “bypass BMS” yet has no diagrams to link to

fail

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Discharge bms can suck my dick.

Second bad stack as a result of a discharge bms just shitting itself for no reason. Anyone know what the bms is in the bioboards thorium? Its a big red thing.

#fuckdischargebms

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Running your discharge through the BMS definitely adds an additional failure vector for the drive train.

When the choice is presented between higher risk to body or higher risk to battery, I’ll choose battery every time. Those are just money.

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Same here, I know I can afford a new eskate even if the ones I have get incinerated and there is nothing to salvage, but I don’t know if I can afford getting hospitalized for a bad crash. I’d like a slow burn fuse with a 100% margin of tolerance but definitely no discharge BMS

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I think its a 120A Daly BMS

Does it look like that?

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Yes it looks very much like that

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