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Old Feb 03, 2013, 01:53 PM
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Joined Aug 2011
92 Posts
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Power issues

Hi guys,

don't know if this is the right place to be but i believe this is a CC issue.
First of my setup;

Trex 700E FBL
Castle ICE2 120HV with YGE cappack.
Align 700MX customwound 510kV YY-wind
Zippy 4000mAh 40C 2x 6S

I know it's not a problem with bad lipo's cause i have 4 sets and cannot believe
they all went bad from october till now storage charged.

That's why it's good to have some logs to see what is going on afterwards.
ESC is setup in setRPM at 2000rpm Idle1 and at a full pitch (+14/-14) climbout the rpm drops to 1550!!!
Last time it really had no problem what so ever.

I also tried FEP..no difference.
Tried 4.02, 3.27...nothing.
I'm suspecting the motor also..

If anyone who can read the log differently please chime in....!
One is with gov, the other on FEP. FW 3.27

Logs can be found on https://skydrive.live.com/?cid=8f365...PSAzWpn9BQA-0Y

CSV file pitch pumps 2 and 3 show the problem i'm having.

I have to add that i changed Auto-lipo to custom 36V.
Does this mean LVC is disabled?

With Auto-lipo on startup it only counts to 7 with a freshly charged pack!
I measured 49,7V on the connectors with a digi voltmeter when hooked up to
the ESC, but still only 7 beeps...WTH

Forgot to mention this...so that's why i suspect the 120HV
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Old Feb 03, 2013, 03:48 PM
Registered User
Joined Aug 2011
92 Posts
Okay... so i analysed the logs for some time now and previously when the heli flew fine
the logs showed when i demanded power from the system headspeed obviously dropped but Power Out increases.

Now it shows that on pitch pumps Power Out % drops in RELATION with rpm.

What gives..? Is this setup related somewhere, i never changed anything.
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Old Feb 03, 2013, 04:34 PM
A man with too many toys
United States
Joined Feb 2001
17,655 Posts
Quote:
Originally Posted by Sirolf View Post
Okay... so i analysed the logs for some time now and previously when the heli flew fine
the logs showed when i demanded power from the system headspeed obviously dropped but Power Out increases.

Now it shows that on pitch pumps Power Out % drops in RELATION with rpm.

What gives..? Is this setup related somewhere, i never changed anything.
That indicates you are hitting one of the limits and doing into soft cutoff mode.

If the battery voltage starts to get close to 36v it will start reducing power to try to keep voltage from hitting the LVC (36v).

If it’s not that:
1. Disable the current limiter
2. Set PWM to 12 KHz
3. Set timing to low
4. Set the LVC to 12v and time flights – that’s the way that I fly.


The only other limiter is the temperature limiter and you can’t change that.


.
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Old Feb 04, 2013, 04:41 AM
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Joined Aug 2011
92 Posts
Have you looked at the logs?
I'm not convinced it has something to do with a limiter but i take any advice on this matter.
Next time i have time for it will be friday so that's a bummer...

Current limiter is set at Insensitive, will disabling it make any difference in the long run?
PWM is and was at 12KHz, timing is at medium but will change that to low.
Maybe i did screw up with LVC or my pack are getting tired. So LVC to 12V will completely
disable any form of limiter? Other than draining the packs entirely.

I time all my flights, even on my nitro's.
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Old Feb 09, 2013, 02:16 PM
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Joined Aug 2011
92 Posts
So i bought some new packs, set the LVC to 24V.
Did a few charge-discharge cycles on the charger and had all lipo's sit 4-5 days in the warmest room of the house.

Just 4 easy runs today including full pitch climbouts again on 4.02 gov.
No more drop in headspeed anymore.. new packs produces noticably more power; so.... damn... bad lipo's!

In the long run, how bad would it be to continue using the older lipo-packs this way?

See the logs of today: http://sdrv.ms/Y0E7xv
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Old Feb 13, 2013, 05:12 PM
Harry from Atlanta, Ga.
Old Sloppy's Avatar
Buford, Georgia
Joined Sep 2006
145 Posts
Quote:
Originally Posted by Sirolf View Post
so.... damn... bad lipo's!

In the long run, how bad would it be to continue using the older lipo-packs this way?
It can cause a crash, Expensive Repairs.

Harry
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Old Feb 14, 2013, 10:16 AM
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Not if i auto it down.. servo's are powered by a separate 2S lipo.
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Old Feb 14, 2013, 03:00 PM
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Olathe,KS,USA
Joined Oct 2000
2,654 Posts
One thing to be concerned about with bad Lipos is that they can fail unexpectedly. So you must be prepared for that.

Also, bad Lipos can be very hard on the input capacitors. It's good that you are running additional caps (YGE Cap pack) -- but still be aware that they can overheat when used with bad Lipos. If they overheat badly, they can fail suddenly -- and the ESC will overheat and possibly fail if the capacitors fail.

Thanx!

Patrick
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Old Feb 15, 2013, 06:33 AM
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Joined Aug 2011
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I'll keep an eye on the logs.
Will get a second pack this spring and to some charging at the field from now on.
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