View Full Version : Discharge temperature?
Hi
Today i measured one of my Lipos 2 minutes after flying.
Measured 60 degress celcius! :eek:
Is that a normal temperature after discharging?
DebianDog
04-26-2007, 02:57 PM
hold on American math...
60 degrees Celsius = 140 degrees Fahrenheit
Yes that is HOT. make sure you do not have a belt too tight or other binding going on.
Ok, well the flight time is quite good?
Anyway will check tomorrow
DebianDog
04-26-2007, 03:07 PM
I thnk you should be "OK" but it is not ideal. Tell me how many Mah go back in the pack and how big the pack is.
I measured a 1300MaH HONGA 20C
http://www.iccom.dk/Hobby/Batterier/LIPObatterier.htm
If we make an pessimistic assumption. 1000 mah. 5 minutes flight time. 1 ah * 60/5 = 12 Amp draw. Well within the 20C capabilities of the battery.
I havent go a decent charger yet. So no Mah calculation yet.
Got a E-station LP4
http://www.hobbyfly.com/el_tilbehoer/batteri_oplader/e_station_lp_4_lader_da.html
And the standart walkera balanced charger.
Im going to get a decent one soon.
DebianDog
04-26-2007, 03:17 PM
With a new battery or helicopter/motor I usually do a 2 minute flight then see how much I put back in. Then start doing longer and longer flights till I hit the 80% rule.
Maybe im drawing too many mah. How will the voltage read at a 80*% discharge?
The heli has an automatich cut of system, thought that was protection enough.
Regards Tommy
DebianDog
04-26-2007, 03:22 PM
Maybe im drawing too many mah.
How will the voltage read at a 80*% discharge?
The heli has an automatich cut of system, thought that was protection enough.
I would bet you are
Depends on the battery
The cutoff has never saved any of the batteries I have ruined :lol:
LoL... maybe i could get a warning og early cut of system. Would be nice!
Otherwise i will continue to abuse these suckers!
creightoncarr
04-26-2007, 11:05 PM
After discharging 80% of your pack and letting it rest for a couple of minutes, the voltage of your packs should be around the nominal voltage per cell times the number of cells you are running. If you're running 3S, your discharged voltage will generally be around 11.1 or 11.2V. Anything much lower after you've allowed your packs time to rest and I think you've probably overdischarged.
Thx very much.
Will try to measure next time.
Btw. What is the fully charged voltage ? After rest.
And yes im running 3S
creightoncarr
04-27-2007, 04:13 PM
Fully charged voltage on 3S should be right about 12.6V, or 4.2V per cell.