Lipo cutoff

[kenai1]

I had my 2nd flight with lipos tonight and the power was good again but I guess I cut the time a little tight as after 20 min the battery just died instantly. (1800 mah) I did not notice any power loss as an indicator. Cracked the cowling on the hard landing.

My BLade CX2 heli always starts to slow down a bit before it dies.

Do other suse a timer or can you notice the power loss before the batteries cut out.

Kenai1

[duck9191]

ya thats the bad part about lipos and a esc that uses a hard cutoff. it can be hard to tell when the pack is near empty then it just dies.

my esc is set to a soft cut off, so it does gradually die out. when i notice it i land asap.

[flydiver]

It's not good practice to fly a lipo to LVC if you want maximum life from it. Try to retain 20% of the battery. So If 20" was LVC I'd bring id down after 16".
Most ESC have an LVC of 3.0v. 3.3-3.5 is much better but few do that so timing is necessary. Older technology ESC using LVC below 2.9v are hard to recommend anymore (some Electrifly's are pathetic) with the newer lipo technology with higher C-rating. The older low C would take the 'abuse' better.

fly

[coougarr]

Always good practice to use your watch or timer. I have a built in timer in my tx and it beeps when it reaches a pre-set time. Besides the fact that you shouldn't run lipo's too low i never want to wait for my lvc cause i don't want to go walking for my plane. Just my thoughts.

Oh... and a watt meter is a really cool tool for predicting flight times. I use the wattsup meter

[kenai1]

Thanks for the information. I will try and keep a closer time on the flight.

I am still not sure why my Helicopter lipos start to lose power and that tells me to bring it down as it is really noticeable.


Kenai1