Kraton ESC (question/confusion) - Ideal LVC for Kraton 6s V5

[RC617]

Background: So I'm still very new to RC cars and I have been looking into what is the target battery voltage when removed from my RC (Kraton 6S V5), after LVC is reached. From the few runs I have under my belt batteries measure at ~3.8##V. From looking online it looks like 3.7V is maybe the normal target. This being the case I was looking if I needed to tweak my LVC, however looking at the Kraton manual and the following thread, it appears this cannot be done:

https://www.arrmaforum.com/threads/low-voltage-cut-off-on-the-v5-kraton.30217/

My confusion is the Firma 150A ESC manual shows that there is a LVC setting. So is the Kraton V5 using a modified version of the Firma 150A ESC and not the standard consumer version? Also, it seems based on what I've read that the default LVC of 3.0V/cell is low (maybe I'm missing something).

I guess ultimately what I'm trying to figure out is:
1)Is 3.8##V post run normal or am I leaving run time on the table?
2)If 3.8V is higher than necessary is there anything I can due to adjust this? From the linked thread I know there are low voltage alarms, but this seems to only be a solution if the LVC is too Low not if it is too high.

 

[ih8nixon]

What's you're charger say it's putting back into the batteries when you charge them? How old are your batteries? What brand, styleand c-rating?

3.8 is a little high, but if you have an older,underrated, or damaged pack the LVC will kick in earlier do to voltage droop.

 

[L3phturn]

What's you're charger say it's putting back into the batteries when you charge them? How old are your batteries? What brand, styleand c-rating?

3.8 is a little high, but if you have an older,underrated, or damaged pack the LVC will kick in earlier do to voltage droop.

Is it cold out where you are? I am getting more voltage drop right now in sub freezing temperatures and when they batteries are at room temperature after running I get 3.74-3.82 volts. I think my ESc is set at 3.4v so I will drop it to 3.2.

If you are getting an early LVC you should run a voltage alarm on the balance lead as you drive as it will alarm when any cell hits the set point. That will alert you if one sell is going bad and dropping under 3v under load. Your ESC can only see total voltage.

 

[RC617]

What's you're charger say it's putting back into the batteries when you charge them? How old are your batteries? What brand, styleand c-rating?

3.8 is a little high, but if you have an older,underrated, or damaged pack the LVC will kick in earlier do to voltage droop.

Is it cold out where you are? I am getting more voltage drop right now in sub freezing temperatures and when they batteries are at room temperature after running I get 3.74-3.82 volts. I think my ESc is set at 3.4v so I will drop it to 3.2.

If you are getting an early LVC you should run a voltage alarm on the balance lead as you drive as it will alarm when any cell hits the set point. That will alert you if one sell is going bad and dropping under 3v under load. Your ESC can only see total voltage.

Thanks for your feedback.

@ih8nixon I had thought I had checked both batteries (I just got a new one) but I wasn't sure so I ran the new one to find out. Running it was reading in the 3.3V range and by the time I put it back on the charger it was in the 3.6V range (battery warming up, like @L3phturn pointed out. I am running in the snow at temps below 20F). The other battery that was reading 3.8#V (at room temp) is a used battery that came with the Kraton when I bought it used so I'm not sure how old it is. So my guess is it is temperature related and some portion maybe due to the age/health of the used battery. Thanks again.

 

[L3phturn]

Best thing to do is pick up a 5 pack of cheap voltage checker/alarms for $20 on Amazon so you can at 3.0v / cell alarm and run them on the truck. That will warm you if any cell drops below 3v under load.

It’s also worth getting one of the checker/balancer/discharger units. They also measure internal resistance.
Tenergy 5-in-1 Battery Meter, Intelligent Cell Meter Digital Battery Checker Battery Balancer for LiPo / LiFePO4 / Li-ion/NiCd/NiMH Battery Packs https://www.amazon.ca/dp/B0178P8H9U/ref=cm_sw_r_cp_api_i_25MSR8DBK11C1DPCM788