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Spektrum Firma 2 n 1 LVC Issues

tigris99

Rock Crawler
Joined
Jan 4, 2022
Messages
574
Location
st louis
As title states, the LVC is either having issues or spektrum has it programmed ungodly conservative or I'm missing something.

First bit. It was below freezing much of this weekend trip/event.

Same exact packs (I have 4 of these same battery packs, 2 have 1 run each, 2 more brand new) 3s 2200mah 35C Ovonic packs.

Before anyone points at battery packs. I use these in 2 rigs. 1 is the Knightkeeper/Tacoma build build (problem) and the other is the Gatekeeper Hilux.

Tacoma (rig with issue):

Spektrum 2 n 1 2300kv

NSDRC RS800 servo direct powered



Hilux (ran perfect all day)

Hobbywing Fusion 2 n 1 1800kv

Cheap "45kg" servo off Amazon, ran off rx power, thus BEC.


Here's the problem. The Knightkeeper kept going into LVC for no reason. Literally tested full battery just off charger night before. Happened with every pack I put in out of the 4 of these packs I have. Was annoying when I got to the event, fired up, got 10ft from the bed of my truck and it went into LVC.

Driving in a straight line suddenly first stage LVC then a couple seconds to minute later it shut down. Unplug battery, plug back in I could go 2 minutes or 30 minutes before it did it again. So in the course of 2 hours I had to reset the ESC several times.

Tried changing packs, even hooked up my spektrum battery tester/programmer (tester is accurate, I verified with 2 chargers and DMM to make sure when i bought it) and hammered throttle/moved steering, voltages went down but shouldn't have engaged LVC. Then hooked programmer up and set LVC to lowest possible setting without turning off.

Now at the same time using the batteries that acted up, now frozen from being in my backpack, I put in the Hilux and ran for 1.5-2 hrs not a single issue.

Which narrows everything down to The Spektrum Firma 2n1 LVC settings or an issue with it.

I cannot find the actual voltage that the LVC does it thing based on what stage chosen. Looked for 45 minutes so far. Trying to figure out best course of action so I need to test and see what is doing what. But I need the factory specs to see if this is faulty or just some idiot at spektrum programmed them wrong.








Sent from my SM-S906U using Tapatalk
 
Manual says... Hobbywing Fusion 2300kv pro...


Should be the same as the Spectrum stuff.

low=3.0v, med= 3.25v, high=3.5v per cell.

Lipo cell default is auto detect, and cutoff is medium
 
Manual says... Hobbywing Fusion 2300kv pro...





Should be the same as the Spectrum stuff.



low=3.0v, med= 3.25v, high=3.5v per cell.



Lipo cell default is auto detect, and cutoff is medium
The spektrum one is the one I need not the hobby wing. I was afraid my post might get confusing cause I was trying to explain that I had gone through all other diagnostic.

Sent from my SM-S906U using Tapatalk
 
if it is enacting LVC 'The red LED will begin a repeating single flash when the ESC enters LVC'
Yes I know, I'm trying to figure WHY it's entering LVC on a fully charged pack just cause it's 35F outside. It's the only rig I had this issue with.

Sent from my SM-S906U using Tapatalk
 
Sorry, I wasn't sure that you were sure it was the lvc.
I'm sure you looked harder than I did; low-medium-high is really vague. I don't see the point of obscuring that info. Maybe shoot them an email?
Do you have the testing equipment to see what voltage you are at when it kicks in?
I'd think a slight dip in voltage due to weather, but lipo is not known for those kinds of dips the way nimh or nicad was.
 
Sorry, I wasn't sure that you were sure it was the lvc.
I'm sure you looked harder than I did; low-medium-high is really vague. I don't see the point of obscuring that info. Maybe shoot them an email?
Do you have the testing equipment to see what voltage you are at when it kicks in?
I'd think a slight dip in voltage due to weather, but lipo is not known for those kinds of dips the way nimh or nicad was.
I put my pack tester on the balance plug and watched the voltage, it wasnt dipping near far enough. But it didn't act up when testing.

Annoying cause rig has been out now 3 times and was great first 2.

Guess as you said, I need to contact spektrum

Sent from my SM-S906U using Tapatalk
 
Reached out, had a discussion today.

Basic summary, the 2 n 1 firma lipo protection is set way too conservative. The rep I talked to thinks medium is about 3.6V. That's a "wtf???" So it's basically designed for LIHV use only because low setting is 3.2 or 3.3V.

Still doesn't fully answer why it was doing it on a pack fresh off the charger.

Means it's getting moved to my LIHV rig, aka the Knightrunner or getting put in parts drawer for a rig that won't see a lot of use where I need full usage of a pack.

Sent from my SM-S906U using Tapatalk
 
Hell, high sounds like it would be 3.8v, which is my storage voltage of choice...:shock:
 
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