Need some opinions on a power dump

[Big Fil]

OK so i've had my Logo 500 3D up and running since Sunday. So far i'm blown away at how great this thing flies and have been getting more comfortable with the thing as I learn the new birds characteristics. All is well in Logo land is well until today on my 9th flight and in the middle of some tic tocs I hear the motor drastically lower it's tone and come down. It did not completely die but as i'm bringing it in for landing I can hear the motor getting lower and lower. My first thought is it must be a thermal shutdown on the ESC or a battery dump. Fuss with getting the canopy off and temp the motor at 105 degrees, ESC at 115, and the battery at 106. Nothing seems alarmingly hot. Threw the cell spy on the battery and voltage was at a comfortable 3.87 per cell after the 4:15 flight. After that I went out a few hours later after getting off work and with a different lipo and flying around real easy to see if it would happen again everything seemed fine until 3:30 minute in BAM same thing. Motor drops in RPM and have to bring her in under falling power. In between the time I landed and fumbled getting the canopy off was about 45 seconds till I could get to the temp guage and noted 108 on the motor, 110 on the battery, and 125 on the ESC in 75 degree ambient weather. BEC was cool to the touch and even temped the servos which were also around ambient. When I did land I still had all servo functions so definately not any sort of lockout, but it would not spool back up. After temping everything on the table where I had my stuff I plugged the same battery back in and it would start to spool but I wasn't going to fly again.

So does this sound like a thermal shutdown on the Jazz 80? Are the Jazz 80s known to have issues the below setup. I would have thought based on how much has been coming out of my batteries and the fact that this bird is super light that the amp draw would be less than any flight out of my Trex600. I've never experienced any shutdowns on any of my CC or Align ESC's and my experience with low voltage cutoffs is that they pulse the motor. Plus the battery still showed plenty of juice left. Any help on diagnosing the problem would be appreciated as i'm loving flying this bird and want to have everything operating well. My setup is as follows.

Logo 5003D
Hacker A40-8-8 13T
Kontronic Jazz 80
Rotortech 560mm blades
70% governed = 2260rpm but was running at 75% on these particular flights and have not tached at that setting yet.

If i'm forgetting some info let me know and i'll try to provide it. BTW no i do not have access to a logger.

Thanks guys.

[BruceW]

Here some thoughts to throw out...

1. Are you sure your in governor mode on the Jazz? If not, then the ESC will not regulate the power properly and will probably go into thermal shutdown under high load (30 second slow shutdown). This sounds similar to other stories I've heard when not in governor mode. If you haven't done it already, go through the Jazz programming sequence documented by Shawn just to make sure.

http://www.helifreak.com/showthread.php?t=51581

2. Hopefully the motor is not drawing too much unnecessary power and causing the problems. It sounds like everything is geared correctly and your head speed is good so that would be lower on the list of problems but something to consider.

3. The tail belt is loose enough, right? The main blades should spin very easily.

Just some ideas to start with.

Bruce

[BruceW]

One other thing... Does it take 12 seconds for your motor to spool up to full power if you just flip straight to idle up from hold?

[Flybar-less]

What LEDs are flashing?
Singles=undervoltage. Doubles=Overcurrent. Tripples=overheating. Quadruples=recieve loss. Sextuples=error.

[Big Fil]

Here some thoughts to throw out...

1. Are you sure your in governor mode on the Jazz? If not, then the ESC will not regulate the power properly and will probably go into thermal shutdown under high load (30 second slow shutdown). This sounds similar to other stories I've heard when not in governor mode. If you haven't done it already, go through the Jazz programming sequence documented by Shawn just to make sure.

http://www.helifreak.com/showthread.php?t=51581

2. Hopefully the motor is not drawing too much unnecessary power and causing the problems. It sounds like everything is geared correctly and your head speed is good so that would be lower on the list of problems but something to consider.

3. The tail belt is loose enough, right? The main blades should spin very easily.

Just some ideas to start with.

Bruce

1. I did go through the programming and set it to mode 4. It does do the full 12 second spool up and govenor seemed to my ear to be holding well. Before I fly again today or tommorrow I will reprogram it to make sure. Looking through Shawn's guide I had not done a mode 1 then mode 4 setup with the main battery attached. When I programmed the ESC I did it on the bench with a 3S lipo.

2. Yeah, everything sounds happy when it's running. I went with the 13T based on Shawn's recommendation for the 8L motor and it seemed to be dead on with the headspeed range I was looking to achieve. I would also think if the motor was drawing to much i'd notice high battery heat and mahs used.

3. Tail belt tension appears to be OK. That was one of my first thoughts but the thing spins really free. On spool down it takes nearly as long as my 600 on a TT does. I will readjust just to make sure and even run it on the looser side. I can't hear my belt ring like i've heard other Logo's do in vids but when setting up I was not concerned about it cuz of everything spinning so nice.

[Big Fil]

What LEDs are flashing?
Singles=undervoltage. Doubles=Overcurrent. Tripples=overheating. Quadruples=recieve loss. Sextuples=error.

You know that is one thing I did not note while out there. I'm guessing that never having a LED to look at on my Align ESC and that it was a bright day the LED did not catch my attention. I will definately see if I can get it to happen again and pay particular attention to the LED flashes.

One thing I have to add is that yesterday it was 75 degrees outside which was warmer then any of the previous 7 flights I had put on it with no issues. Living in California though my ESC must be able to cope with anything up to 100-105 degree ambient in temperature if this ESC is in fact thermaling.

[OICU812]

If for some reason you do find that it is thermalling, which it should not be but,,, if it is simply put on a heatsink on the smooth plate side and that woulod do wonders in this regards.

[Big Fil]

If for some reason you do find that it is thermalling, which it should not be but,,, if it is simply put on a heatsink on the smooth plate side and that woulod do wonders in this regards.

Do you know what temperature the Jazz 80's shut down at? When I took a reading 125 degrees did not seem overly hot but this is also my first experience with Kontronic. Also should I be mounting the ESC with the plate towards the outside? At the moment I have the label side pointing out as the plate side seemed like an ideal surface to mount from. If I were to run a heatsink it would need to be flipped around so the label side was down. Any threads on installing the heatsink?

Hopefully this afternoon I can get out, reprogram the ESC and see if it does it again. Unfortunately it's supposed to be 5-10F degrees cooler than yesterday. If it does happen again I will pay attention to the LED blinks and report back.

[BruceW]

I have measured mine at 130F (avg ~120F) after some hard flying and it never seemed to come close to thermaling. My label is pointing down so the plate is more exposed but it doesn't sound like your were pushing the helicopter to its limits when shutdown started happening. Just for grins, fly with the canopy off and the label pointing down and see what happens if your new programming session doesn't fix the problem.

Also, I have not done the heat sink mod (yet) and have flown in 80F weather with no heating problems.

[Big Fil]

Well it happened today again on each of my two flights even after reprogramming to mode 1 then mode 4. First one happened at 4:15 and the second flight at 3:30. I did get a chance to look at the LED and it was flashing two short blinks followed by a longer one. I'm interpreting this as a 3 blink thermal shutdown, no? Ambient temp was 63F so quite a bit cooler today. Highest temp on the ESC was 134 degrees right at the top end right where the output leads exit the shrink wrap. Doesn't seem particularly hot so could this mean I have a defective ESC that cuts off early?

I'm going to try one more thing before contacting Kontronic and that will be to flip the ESC over so that the plate is facing upwards. I can understand doing the heatsink mod if I was really banging on the thing and flying it super hard in hot weather but i'm not doing either at this point. I'd really hate to put the Align ESC on this bird but it has flown my Trex 600 in 100 degree weather and had to have more load given the weight is over by more than a pound swinging larger blades.

[Finsta]

Dude -Sorry to hear of the issues. I'm sure you'll get it worked out. Had to wipe the tears from my eyes how you stressed several times in your post of how you had to fuss with that canopy. It sure is a pain. I don't know how someone walked away form that design. Looks cool, but very annoying I must say. To better times!

[Big Fil]

Thanks Finsta but they are actually small issues in the end. I am absolutely in love with how this bird flies and am considering the problems i'm having minor annoyances.

[ozsteel]

I'm not sure if I'm delighted or unhappy to find this thread.....

I'm having exactly the same problem; as it turns out also on a Logo 500 3D which is also flying great except for the ESC shut-down problem.

I'm flying...

Kontronic Jazz 55-6-18
Hacker A40L-8 Pole, 8 turns ...... 1,300kV
FlightPower 6S 5,000mAh
Blades 530mm carbon
Futaba 6EX with R606FS receiver
Radio powered by BEC - no secondary battery

I'm only getting into a hover and having the ESC shut-down on me after 2 or 3 minutes. It seems to be running fine at about 2,300rpm - using a 22 teeth pinion of mod0.5 so only running at about 55% to 60% on the TX. I'm thinking of changing this to 17 teeth to run at 75% for about the same head speed.

Once the shut-down starts, the motor seems to keep running but at much lower revs and will stay at this speed even if I try and throttle up but once the stick is moved to 0% the motor shuts down and will not restart. By disconnecting the battery and immediately reconnecting it the ESC will reinitialise giving the expected beeps and will function "nomally" for another 2 or 3 minutes and then shut down as before.

I haven't measured any temperatures but everything seems to be only warm to the touch.

I'm definitely flying with the ESC in Mode 4 although I haven't gone back to Mode 1 and then to mode 4 again although I was planning to try this - it seems this doesn't solve the problem however.

One thought I have is that after setting mode 4, on the very next spool-up the ESC establishes the governor parameters from the motor/rotor combination automatically and remains with these from then on. It might be that the I have not allowed the ESC to establish the governor parameters properly so I might try this when I'm next able.

Guys, help!....it would be much appreciated.

[ozsteel]

I've been reading other threads to try and get a handle on this shut-down problem....maybe it's the BEC that's being overloaded. I'm running three 9252's and a GY401 with 9254 on the rudder. BEC maximum load is only 2A on the 55-6-18.

Could this be causing the problem?

[Big Fil]

Hey Ozsteel, I noticed that you listed some contridictory numbers for your Jazz and i'm not sure weather you have the Jazz 80-6-18 or the Jazz 55-10-32. If your running the 55 I wonder if you could be running close to the limits with a higher draw power setup. Just a thought.

On my Jazz 80 i'm using a seperate BEC so I shouldn't be getting any extra heat from that. Since heat is obviously my issue the first thing I need to do is flip the ESC over so the cooling plate is facing out. That may have been my first mistake and mounting that way may have not given adequate cooling. If I still have problems after that I will probably look into mounting a heatsink as well. How do you have your ESC mounted in regards to the plate?

Let's keep sharing info till we can get this solved. It's unfortunate that we are dealing with this but fortunate that we can work out the solution since we have similar setups.

[Flybar-less]

Check out the heatsinks.
Thermal epoxied some heatsinks on.

http://www.helifreak.com/attachment.php?attachmentid=33316&d=1198125118

[tomas]

Hey Ozsteel, I noticed that you listed some contridictory numbers for your Jazz and i'm not sure weather you have the Jazz 80-6-18 or the Jazz 55-10-32.

Actually there is also a 55-6-18 but it only has a 2Amps bec

[BruceW]

The Jazz 55 has no BEC and would be worse than the Jazz 80 for current loading when run on 6S.

[OICU812]

the 55 is not adequate imho, the Hacker motor you list will pull well over 100 amp spikes on 550mm main blades. The 80-6-18 has not given me one bit of issue ever in regards to any kind of shutdown and I have purposely put the helis to the limit with this esc. I have not shot the temps, last summer at end anyways I never had felt my esc to ever be anything past warm. I do have mine with a heatsink as a precaution as I do all my escs, but,,,, from what I did see I have a hard time imagining needing one to be honest.

[Big Fil]

For all you guys that have installed heatsinks it looks like most are thermal epoxying them to the plastic that is covering the plate. Shouldn't the plastic shrink wrap be removed and the heatsink mounted directly to the plate. Plastic is a heat insulator so aren't you pretty much crippling the benefits the heatsink can provide?

[Flybar-less]

That's because we are such good craftsmen!:YeaBaby:

I have been accussed of not cutting the heatshrink away. But yes, cut it away.

[ozsteel]

Apologies for my typo.... should read 55-6-18

The 55 does have a 2A BEC which I am using but with four digital servos - probably too much load here - but what do you all think?

I have the ESC mounted with double sided tape with the label facing outward - it appealed to my asthetic sensibility that way! No way for heat to escape here at all so I'll turn the ESC around and try it that way.

I haven't actually measured any temperatures but the ESC, motor and battery always feel at best warm - maybe I need to check the back face of the ESC.

I'm using a 55-6-18 because that's what Brian at Perth RC suggested; also the Hacker motor and 22 tooth pinion. The motor is clearly able to pull very high amps becuase if I run it up to 100% I can get an outrageous head speed. I've set a flat throttle at 60%.

I also have a 17 tooth pinion so the ratios are as follows...

mod0.5 gear = 212 teeth
Pinion = 22 teeth
Gear ratio = 9.64
Motor kV = 1,300 rpm/V
6S = 22.2 V
Motor speed at 100% = 28,860 rpm
Rotor speed at 100% = 2,995 rpm
Rotor speed at 80% = 2,396 rpm
Rotor speed at 60% = 1,797 rpm
Rotor speed at 60% governed by ESC = 2,310 - why?

Pinion = 17 teeth
Gear ratio = 12.47
Rotor speed at 100% = 2,314 rpm
Rotor speed at 80% = 1,851 rpm

So, should I change the pinion to 17 teeth? or something else? Do I need to change the ESC to a Jazz 80 which will be expensive as the Jazz 55 its now "used"?

Is this a heat problem or something else?

I should add that I'm only good for hovering and mild flying so don't think of extreme set-ups here - only beginners!

Appreciate your help, Anthony

[BruceW]

I'm not sure if Australia has different labeled ESCs but here in the states the two that are of interest are the Jazz 80-6-18 and Jazz 55-10-32. The Jazz 55 does not include a BEC and is rated for 55A and up to 10S. The Jazz 80 is rated for 80+A, has a built-in BEC rated at 5V/4Amps and goes up to 6S.

If your running in governor mode you should not set your TC above 85% otherwise the governor can't do its work of maintaining head speed under load.

Based on your specs, I think you would be best with an 18T or 19T mod 0.5 pinion to give you 2300-2400 head speed.

If you have a BEC that is only rated for 2A, you need to upgrade but you should list your electronic configuration also.

[ozsteel]

I'm using a Jazz 55-6-18. Have alook at the spec sheets from Kontronik at...

http://www.kontronik.com/Datenblattjazz.htm

Electronics as follows...

R606FS receiver
3 times 9252s on cyclic
GY401 and 9254 on the tail

BEC is 5V (I've measured this), 2A rated according to the spec sheet.

I'm running a flat TC at about 60% to get a governed head speed of about 2,300 rpm with 22 tooth pinion; mod 0.5 main gear.

[BruceW]

Wow, never seen that ESC listed over here in the states but it looks like it performs the same as the Jazz 55-10-32 except for the cell count. I know others have run the Jazz 55 in their 6S Logos but it would be pushing it very close to the limit on most flights since others have recorded 100+A spikes on 6S.

I think your S9252s will pull less than some of the other servos but all 3 under load could easily pull more than 2A. It would be best to run a separate BEC.

If your running 60% and getting 2300 on a 22 mod 0.5 gear you should probably drop down to a 18T and take your TC to around 85% ( or 19T at 80%) to get the same head speed. Since the Hackers like to run with a faster RPM that is why I suggested 18T instead of 19T but 19T would give your more room to go faster if you wanted. I run mine at ~2320 and it seems like plenty for what I want.