HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 30, 2013, 07:11 AM
Canadian Bacon
flypaper 2's Avatar
Kingston, Canada
Joined Jun 2004
12,903 Posts
After a flight, are tha batts warm at all.? They do generate some heat of their own depending on the amp draw/load. If they are coming out cold, you may be able to tape over the compartment just to retain the heat. I make these socks from the thin foam that electronics comes in. Taped together with Scotch tape and a closure held shut with velcro. May have to play with the insulation a bit. Too much may overheat the batt. I like them to come out just warm in my hand.

Gord
flypaper 2 is online now Find More Posts by flypaper 2
Last edited by flypaper 2; Jan 30, 2013 at 05:22 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 30, 2013, 04:20 PM
That's a funny word
NE Ohio
Joined Apr 2003
3,686 Posts
Quote:
Originally Posted by sgrouts View Post
Testing results:
I got my two lipos without charging them after the test flights that I already told you about.
Room temp= 24 C
I connected a lipo checker to the balance port.
I also connected my HK wattmeter that usually measures a top Amperage draw of 55A with lipos fully charged.
Both of the lipos started with 3,85 each cell with some cells at 3,84 and gave at most 25-27A at WOT.
During that WOT the individual cells dropped at 3,55V the minimum. To be honest they were holding at around 3,65 but after a few secs I saw 3,55 at some cells.
So no below 3,30V dropping as I was expecting.
Time to check other things.
I reprogrammed my moxie 80A esc (low pricerc) using my programmer card and changed two settings:
Gas pedal set to high from medium
Model start set to low from high.
Repeat the tests using both lipos:
They both gave almost 45 Amps each!
And without recharging after the problematic flights...
As I said this is a new setup on a new wing that I built.
I have used my esc at the past with 3s lipos on smaller motors,
But now I am using an NTM 42-38 motor with a 14x8 folding prop.
To be honest I do not even know what that esc settings are doing exactly.
Thank you for helping.
Sakis.
I guess all bets are off if the readings weren't taken at actual WOT. I surely don't understand those esc settings , but WOT should be WOT regardless of state of charge , right?
gulio is offline Find More Posts by gulio
Reply With Quote
Old Jan 31, 2013, 04:36 AM
I love my HammerHead wing...
sgrouts's Avatar
Joined Jun 2012
727 Posts
Flypaper, thank you for the idea.
Gulio, I can't even guess what those parameters actually do regarding motor control and why they limited the amperage draw from 40+ to 20+.
I asked from lowpricerc a programming card users manual, but they replied there is none. Strange things...
The sure thing is that cold affects lipos so I will implement a way to protect them from high speed cold air flow.
Thank you.

Sakis
sgrouts is offline Find More Posts by sgrouts
RCG Plus Member
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question If you wish to charge the included battery from an AC power source, you will need the mikeydrc United Kingdom 5 Jan 28, 2013 04:52 PM
Discussion Help, Lipo Battery wont seem to charge up all the way j3noob Batteries and Chargers 3 Jan 20, 2013 05:54 AM
Sold HK F30A ESC's flashed with SimonK w/ bootloader 3 left acuralegendz Aircraft - Electric - Multirotor (FS/W) 3 Jan 02, 2013 07:11 PM
Discussion Need help....struggling with my next step thomaslambo Beginner Training Area (Heli-Electric) 10 Dec 30, 2009 02:55 PM
Discussion Why is my brushless SS struggling with a 2s lipo? polar8 Power Systems 6 Feb 12, 2008 10:40 AM