psk560

My Feedback: (12)

Ok, here is what I have:

thunder power 1320 3cell
cc pheonix 25
axi 2212/34 apc 11-4.7
fma 5 channel reciever
hitec servos
blue board foamy. about 14 oz

I flew it today for about 14 minutes and the motor starts to have short pulses of power. I figure I'm running short so I land. The li-po is not hot by any means but it was a tad bit warm. I just want to make sure that is normal. I let it cool and then recharged it. Never got warm in recharge. All my other batteries (nicad/nimh) do get a little warm too but this being my first attempt at Li-po I want to make sure a little heat is ok.

Second;
What are the best settings in the programing of the cc25? specifically brake type?throttle type?timing advance?cutoff type and soft start. Someone else set this up. He has been doing this for a bit but I lost the instructions that he had marked what he programed. I just wanted to make sure all was ok in the programing and give it a try myself. Is there a way to check what selections have been made?

Thanks for the help.
craig

vanman

My Feedback: (2)

Craig

If the Li-Po is only warm you are fine, it should not get HOT. Mine do not get warm during charging either.

I program my customers and my own CC as such.

7.2v cutout (when running 3S Li-po's)

Hard cutoff - I used to set them to soft cutoff but found that ifyou are simply flying around easy (in other words not fast and not hovering) it can fly for quite some time in the soft cut stage....not sure if the voltage ever gets below 7.2 when in the soft cutoff or not, but I noticed the pack seemed to be much lower than normal.

Soft Start - easier on the motor, gearbox, airframe, etc

Brake - Disabled - this allows the motor to free spin. I have also notice an increase in control while in a hover since when you bring the motor rpm down the brake does not activate.

Frequency I leave alone

Throttle type - leave at auto calibrate, this feature automatically calibrates the throttle to the throw of your radio......

Hope this helps!!

Bill

psk560

My Feedback: (12)

Vanman,

A few more questions for ya,

Why not 9.0 volt cutoff for a three cell pack?


Electronic timing advance, CC put a star next to standard advance timing. I assume that's what you are supposed to choose is that correct?


Hard cutoff? What does that mean? When voltage on battery goes below certain voltage the motor will automatically shut off for good?


Thanks for your help,
craig

vanman

My Feedback: (2)

The cutoff differes by who you happen to be talking to.....

I used to use the 3 volt per cell theory which would be 9 volts. I noticed that my voltages were always below 9 volts when I would finally land and quit playing....before I started programming my ESC's.

Then I noticed in one of my speed controller instructions that it said to cut at 1/3 the rating of the pack, in this case it would be 7.4volts. I have not had any trouble at this setting and have several hundred cycles through each of my batteries. The guys that we fly with are using the same settings and have litterally hundreds of cycles on each of their batteries.

I do say that if you are not comfortable using the 7.2v setting then use the 9 volt setting, it will simply shorten your flight time a bit, but will add a measure of protection for your packs.

The timing I have always left at standard timing.....not sure what or when that would be used.

The cutoff describes how the ESC will control power to your motor when it reaches the cutoff voltage. A hard cutoff will stop the motor abruptly when it reaches the cutoff point. The soft cutoff will slowly reduce the rpm of the motor and then kind of cycles it until the low cutoff is reached. I was setting mine to this setting but have been wondering about my actual pack voltage, when I am simply flying around at a very low throttle setting. It seemed to me that I could fly around in the "soft cutoff" for quite awhile and am concerned that I may take my packs below the 7.2v point..... I have not confirmed this with a volt meter yet, just a feeling.....so I went back to the hard cutoff setting until I verify where my packs are on the soft setting.

In the hard cutoff setting, you can cycle your throttle stick and usually get a small additional burst of power to help get the plane back on the ground. You can also cycle the throttle stick and then use a low throttle setting to get a little run time on the motor again after the initial cutoff. If you should reach that cut voltage again it will cut the motor again...... and so on.

Hope this helps....

Bill

Time Pilot

I don't know if this has anything to do with your problem, but how many servos can you run with that ESC at 11.1 Volts? I know the 20P is 2 micro servos....