KK2.1.5 battery voltage

[coppercanyon]

Hi all, pretty new to multirotor and I have a question about my KK2.1.5 board. On the top of the board is a connector with 2 pins that is labeled Bat., do I need to use a JST plug from here to my PDB to get my kk2.1.5 to read my battery voltage on the display? And if yes, then can I set the up the low voltage alarm on the KK2.1.5 board to go off at my pre determined voltage?

 

[andybenton]

you would be completely correct. if you don't have the appropriate jst connector, I cut the third socket off of a servo plug and used that.
be careful with polarity in this case. (shouldn't you allways be)

also, my kk2.1.5 doesn't read voltage correctly however. plugging in a full 3cell battery the kk board shows nearly 15v. so I set my voltage alarm by charging my battery, checking the voltage the kk board gave me, then discharging the battery (with my charger) to "dead" state, I plugged it all in again, and noted the voltage show on the kk board, luckily enough it turned out to be the same amount of variation when full, as it is when it was low.... so I just did the math and set my voltage alarm based on how far off it was.

I.E. you want your low voltage alarm to go off when the battery voltage gets to 11.3v. but when your battery is actually at 11.3v your kk board says the battery is at 13v. so set your low voltage alarm to 13v instead of 11.3. easy enough, and it seems to be consistent.
1
sorry for the long post, but I damaged a battery on my first flight with the kkboard, puffed it really good lol

 

[coppercanyon]

Thanks Andy. I figured I was correct in how to get it working but its nice to have verification. And thanks for the heads up on the incorrect voltaage range. I will cross that bridge when I come to it.

 

[andybenton]

no problem, just wanted to give you a heads up on the issues I had.

 

[HarleyRev]

My kk2.1.5 has the same issue , it reads .7 volts higher than actual voltage. Ive read in the newer versions of software for the kk board you can adjust the voltage problem on the board itself. I have not upgraded yet as my quad flies fine.

 

[andybenton]

yeah, It seams to be relatively common.

not to hijack the thread, but I see your in Louisville, where do you fly? im just about 45 min south of you. haven't ever ran into anyone on a forum this close to me, so excuse me if its out of line to ask. but currently I only fly with my father in law, allways good to meet people that are in the hobby.

 

[1387]

Newer KK2 firmwares have the ability to adjust the voltage read out. Mine was about .3V off, too.

 

[HarleyRev]

I usually fly in school yards, but I am new to this so I havent found a great place yet. Do you live around Etown ?

Gives me an idea of flying at Freeman Park, I go there quite often on my motorcycle.

 

[andybenton]

I do actually live in Etown now. my uncle is one of the head guys at the park there. i go out there to run my boat. its a good time.
https://www.youtube.com/watch?v=1xVDLJGINl0

old video, pre lipo and some other upgrades, much faster now. but that was filmed at freeman lake park over by the barn where you can rent boats and stuff.

 

[William A]

Ive read in the newer versions of software for the kk board you can adjust the voltage problem on the board itself.

Can you hook a bro up with this info ?

My searches come up zilch.