Kraton What’s your LVC (low voltage cut off) for your stock (BLX 185)?

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East tactics

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Arrma RC's
  1. Kraton 6s
I’m curious what everybody else is experiencing here. I have the BLX 185 stock ESC. I’m noticing however The LBC is kicking in with my cells are around 3.75 to 3.8. Honestly that seems high considering storage mode is at 3.8. So I checked the statistics on armor.com and the LBC cut off for these is 3.2. So why is mine cutting out at 3.75? Can you check the manual for adjusting the LVC setting it doesn’t exactly let you Meticulously adjust it. It just lets you choose between lipo and NIMH.
After you hit LVC what level are each of your battery cells at?
 
On the BLX it cuts off at 3.2 x xS equivalent (6S=19.2V). It doesn't care what the individual cell voltage is as it has no means of measuring.
Typically mine recover to ~ 3.35V if I ever make the mistake on running them that low.
3.8V upon recovery is not normal unless you have 1 very weak cell that collapses under load. You would see that cell being significantly lower though.

Are you sure its the LVC kicking in and not over temp? Common mistake to make. Power on/off and see if yo get more runtime after letting it cool down.

There is no LVC adjustment on this ESC, selecting 'NimH' will disable the LVC but I don't think that is your issue.
 
Mine usually end up around 3.5... sometimes lower, but never as high as 3.8
Yup 3.5v at rest is about where it should be with a true high discharge lipo, cheapos usually end up at 3.7-3.8v. People always forget about voltage sag and a low discharge lipo will have a lot more voltage sag than a high discharge one, hence the resting voltage of 3.75v.
 
With the smc precision lipo alarm voltage sag is accounted for. Even after my alarm hits and my pack settles I am sitting at 3.7 volts per cell. I don't have the best packs (IMO) but I also don't feel like I am losing runtime. In fact, I set my lipo alarm to 3.5v (normally set to 3.7v) for a test and sure enough when the alarm hit and the pack settled I was sitting at 3.5/3.6v.

If it is the esc lvc (which I don't trust) it would be much lower than that. So really I would say just get the precision lipo alarm and don't trust the esc lvc.
 
If your cells are 3.7/3.8 after your lvc triggers and your pack is settled then you are fine. If your lvc hits and your pack cells are lower than 3.6 then you should worry.
what do you mean by settled?
Actually according to the Blx185 specs the lvc cutoff is 3.2 (which seems way low) I'd be happy with 3.4, or 3.5.

UPDATE - I believe I found the issue. turns out I have a bad cell in one of my batteries that is draining much faster and is off from the others. My ESC is basing the love voltage cutoff, off of that cell... so it checked my my cell levels immediately after the lvc hit, and that cell was at 3.33... so it read out was 3.33, but it probably triggered the 3.2 threshold in the ESC. I then checked my other battery, which is fine, and all three cells were at like 3.8 ish. so I unplugged the bad battery, and ran the Kraton on 3s from the good battery to see when the ESC cut out again. It ran for another 5 minutes and cut out. I checked all the cell on the good battery immediately. it was showing 3.45, 3.39, 3.43. Which is what we should expect.
 
The ESC doesn't know the voltage of individual cells, only the total.
Yup but if you have 1 bad cell it throws off the total voltage reading so lvc kicks in.
 
I know, but East tactics up there seems to think that the LVC was triggered by that single cell...
Could still be that one cell is dropping hard when under load, then by the time he checked it, it was showing 3.3V. From the few packs I had where cells died, they would do that. Drop to sub 1V when under load, then recover quickly to a lower voltage than the rest.
 
The ESC doesn't know the voltage of individual cells, only the total.
interesting... thats good to know... still the one bad cell is bringing the others down. Odd tho... why does the spec on the BLX185 say the LVC is 3.2? wouldn't it instead say... 9.6 for a 3 cell battery. And also... how would the ESC know the difference between a 3s battery and a 6s battery, seems to me it would have to know each cell. Im not saying your wrong... just bringing up points, perhaps to get more clarity. Thanks for the response, I do appreciate it.
Could still be that one cell is dropping hard when under load, then by the time he checked it, it was showing 3.3V. From the few packs I had where cells died, they would do that. Drop to sub 1V when under load, then recover quickly to a lower voltage than the rest.
That make sense, I bet that is part of the issue as well. thanks for sharing... I just need to get a new battery. Its definitely the issue, not the esc.
 
It's strange actually. My wife has a 3STyphon and I have an Infraction. The Infraction had the 185 at first I upgraded to a castle MM8S and on a hunch, tried the 185 in her Typhon. The BLX100 in the Typhon and the 185 in my infraction both were shutting off at 6.7 per cell.

But ever since I put the 185 in her Typhon, it has been shutting off at 3.2 per cell. I think, and my hunch was the amp draw on the units. It just seemed like it would be less work on 3S and a smaller motor.
 
@East tactics The ESC guesses the cell count. That's why it won't even arm on a 5s battery unless you turn off LVC! Because it can't tell if it's a full 5s or a near empty 6s. It would have to have a connector for the balance port to read individual voltages, which would add complexity with little benefit.

It's always stated in voltage per cell because if it detects 4 cells the total cutoff V will be different than with 6s. I find it much easier to think in terms of volt per cell too. Saying a 6s pack is at 22.8 means nothing to me, but 3.8ish per cell I know what's going on. :)
 
@East tactics The ESC guesses the cell count. That's why it won't even arm on a 5s battery unless you turn off LVC! Because it can't tell if it's a full 5s or a near empty 6s. It would have to have a connector for the balance port to read individual voltages, which would add complexity with little benefit.

It's always stated in voltage per cell because if it detects 4 cells the total cutoff V will be different than with 6s. I find it much easier to think in terms of volt per cell too. Saying a 6s pack is at 22.8 means nothing to me, but 3.8ish per cell I know what's going on. :)
That said, it's odd that it can figure out a 3S, 4S and 6S, but not a 5S. I'm now using a blx185 with 3S in a stampede. Although... I am having a weird issue when running... hm....

https://www.arrmaforum.com/threads/blx185-esc-acting-odd.23287/
 
That said, it's odd that it can figure out a 3S, 4S and 6S, but not a 5S. I'm now using a blx185 with 3S in a stampede. Although... I am having a weird issue when running... hm....

https://www.arrmaforum.com/threads/blx185-esc-acting-odd.23287/
5S is right in the tolerance of 4S and 6S and the ESC can't determine if you have a fully charged 5S (4*4.2V=21V) or a near empty 6S (6x3.3V=19.8V).
Similar is true on the 4S side. ESC's are dumb, they only see what is attached to the main battery leads. Rest is just written explanation as it would be for a perfectly ok pack i.e. per cell equivalent.
 
Which is why I turn them off completely on the hobbywing and use the lipo alarm attached to the balance leads. Simpler, easier and more accuracy. My drones would do the same, average the cells based on voltage. If you can't fit a lipo alarm on the drone you have to learn to watch total voltage and stop flying when you are at the "lvc" point. On my drones though because I know how they act I just set a timer that starts as soon as I arm. 3/4 minutes after I arm my alarm sounds and I land. My packs are always 3.6 (drones we discharge more overall) per cell. My batteries from even 4 years ago for my drones still balance and have the same runtime. Lipo maintenance is too easy really. Just takes time and effort.
 
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