L600/Jazz thermal

[th3tick]

So, today on my second pack, the ESC overheated, and I landed without incident. As the stuff below shows, I've got a jazz 55-10-32 on this bird, but from my eagletree, I spent most of the flights well below 35A.

I have a heat sink ordered to be put on it, but I'm surprised to be thermaling at this level. Any ideas why it would?

Attached is the eLogger screenshot. I know the headspeed is a bit hot, but still...

TIA,
John

[Klinger]

Cant see any reason there why it would have thermalled. The Eagletree has been known to interfere with the jazz ESC's and mine will regularly come up with a thermal fault on the jazz when using it but it never thermals when not using it. I wouldnt be concerned unless it thermalled without the eagletree on it. Also what the hell size packs you running to discharge 4600 mah and run for over 10 minutes :wow2:

[Team-MAYHEM]

If you look at the voltage, it looks like two flights on the same graph...

[th3tick]

Yup, two packs ;)

John

[th3tick]

I've got Jazzes on three other helis, all with the eLogger, and no issues. I did notice it came down warm after the first pack, and then on the second was the thermal.

The EagleTree bit is news to me...
John

[Klinger]

I've got Jazzes on three other helis, all with the eLogger, and no issues. I did notice it came down warm after the first pack, and then on the second was the thermal.

The EagleTree bit is news to me...
John

:thumbup: Two packs, that better, thought i was missing out on some new energy source :). The eagletree / jazz fault is fairly widely known, can garrantee it wont happen all the time but for me it certainly only happens when i'm running the ET! Again once you've got your graph info try it without the ET connected and see how it goes!

[OICU812]

So other then light indication, what was the actual temperature on the plate of the esc? I do not see a temp on the FDR, did you shoot the temp at all?? I know the NEU has bursts well above what the 55 can deliver in respect to amperage, a super quick jump can cause a false thermal SD on the 55. Not saying this is it, but you should prove out what the actual temperature is.,, the 55 is to small for the NEU, as much as I don't like to I am running a CC85 on my NEU machine till the Jives come out. So far the best working motor for the 55 on the L600 has been the Tango 45-8 from my findings so far. The Orbit as well is far to demanding for the 55 to, I had multiple HV SDs on it and gave up and went PJ on it to.

[th3tick]

No, didn't get an actual temp. However, I usually feel by touch, and the ESC seemed abnormally hot after both flights, so I believe it. Will bring my temp gauge next time.

Heatsink should be here soon... but not soon enough ;)

John

[th3tick]

So, Klinger, are you implying it's an artificial thermal the eLogger causes, or do you mean it causes it to overheat more?

John

[Klinger]

So, Klinger, are you implying it's an artificial thermal the eLogger causes, or do you mean it causes it to overheat more?

John

Its not casusing it to overheat anymore just a false trip.

[th3tick]

So, today, got out with two packs, and I think I've got a real thermal on my hands...

I put a massive heat sink on the aluminum plate. After pack one, 5 minutes, so about 50% (still breaking in), somewhere up around the two caps that stick out of the end that plugs into the pack, I got a 149.5 degrees measurement.

After the second, similar flight, it came down at 159 in the same area...

I've been flying it with Normal governed to 50% which comes out around 2200 headspeed, and Stunt1 at 55% which comes to 2300. Still need to tweak those down some... I'll probably try 40 and 45 next.

Is it the low governing numbers that are leading to this extra heat? I'm still consistently under 35A, so am pretty confused.

Or, should I not worry about the temp at the caps? No thermals today...

TIA,
John

[Wbird]

Fairly new to these parts but my understanding is not to go below 50% on the jazz for governor and as with any ESC you are better to gear it down and run somewhere between 70 & 80% governor. Easier on everything involved if you use the Gearing advantage rather than reducing the governor. May be causing the unwanted heat you are finding.

IMHO.... Good luck

[th3tick]

I'd love to go to a smaller gearing, but the 13T is best I can do...

Wondering if I need to abandon Neu for this bird...

John

[Eyon]

100% correct wbird.

You have the wrong pinion John. You need to aim for your 3D headspeed at around 80% of the governor mode. at 50% you WILL thermal it. I own at least 15 ESCs between 6A and 220A, cheep and expensive, and only the Kontronic PowerJazz has the ability to partial throttle for long periods of time.

Think of it this way, an ESC doesnt limit the voltage going to the motor, it works with a PWM system and gives the motor full power for short periods of time, so at full power an ESC will run at its coolest!! At half power, the ESC is only letting full power through for half the time, so its got to stop the rest of the full power, meaning, it gets very hot!

Hard to explain, but think of it as a gate, at full power everything flows fine, at half power, only half the amount can flow, but you get a big backlog of "heat".

I am sure someone can explain better than me!

[LITHIUMSTATIC]

I'd love to go to a smaller gearing, but the 13T is best I can do...

Wondering if I need to abandon Neu for this bird...

John

I've seen a CC85HV ran with the 1912 on a Logo and they really liked it.

I decided to go to a Tango 45-07 and keep the Jazz 55 as I don't need a brute power motor for my flying. The 1912 was a beast I couldn't tame on my Logo...

[th3tick]

I decided to go to a Tango 45-07 and keep the Jazz 55 as I don't need a brute power motor for my flying. The 1912 was a beast I couldn't tame on my Logo...

That's exactly where I think I am now, too. What pinion are you using? 14T/0.7 looks about right...

Shawn, you said 45-8, but that looks barely better than the 1912, with 800 instead of 825, no?

EDIT: Playing around with a headspeed calculator sure makes it look like the 1912 is closer in its actual rating to around 950, or at least mine is... Prior to the crash of my Mk I, its headspeed was in the 2500 range in the "normal" governing range...

Thanks, all,
John

[Wbird]

John PM'ed me about this so I thought I would post my reply here in case anyone else could use the info. Also posted a FDR graph on the Sticky post at the top if anyone is interested.


Re: Tango 45-8 pinion

--------------------------------------------------------------------------------

Quote:
Originally Posted by th3tick
So, which pinion are you using with that Tango on your Logo 600?

Disappointed to have wasted so much on a motor, but...

Oh, and with it, what are your throttle curves?

TIA,
John


I am using the 13 tooth right now and am waiting on the 12 tooth. For throttle I have the 3 modes set up differently for testing. Mode 1 65% *(haven't tacked yet but assuming 2100 rpm), Mode 2 70% (2200 rpm), Mode 3 75% (2300 rpm). For AP I have been messing with Mode 1 which also has a fair bit of expo and reduce rates. Mode 2 & 3 I am running the same rates & expo which are quite fast and responsive.

I origioinally bought the motor because of it's efficiency. I know it isn't the most powerfull motor on the market but I am doing AP first, then play second. (at least that is what I keep telling myself) LOL. I am finding that compared to stock power on the T-Rex, the Tango is a huge improvement. Much more power than I am used to and much more than I am good enough to use to full potential.

[th3tick]

Wait... There's a 12T available? OK, I see MIK04212. Anyone stocking it, or expecting it soon?

I also wonder the difference using the 623s...

John

[OICU812]

Running 620s is putting alot of extra load on, and runnig a 55-10-32 that low on % is what is giving you the heat. The 55-10-32 is simply not enough on the 1912 for the 6003D unfourtenetly. On my 1912 machine I have resorted to a CC85HV, not as good as the Jazz, but it does work much better than my old CC85HV with the newest firmware etc they have. Until the Jives come out this is really the only safe option imho.

[OICU812]

Yes also I have a machine running the Tango 45-8 with 13tooth, works fine, but I am running 600mm mains on it as well. The 45-8 will only pull max of 85-88 amps so it is a much lower draw than the NEU. That 1912 you are running will peak out at over 110 amps easily, I have graphs on it and that is what I saw, the high amps and low % on governor are driving your heat issue for certain.

[th3tick]

So if I intend to stick to the 623s, would I be better off with a Tango 45-7 or -8? I'm leaning towards the simpler replacement of the motor than learning the CC ESC at this point.

At least I think it's simpler ;)

John

[Wbird]

I also have a set of 620's I will be trying out once I get a feel for the 600's for comparison. I will post some data on them as well once I get to try them out a bit.

If you are replacing the motor with the Tango I would probably go 45-08 for 3D. I would like to try the 45-07 myself just for a little slower headspeed and longer runtimes for AP (also considering 650's) but 2200 seems to work well for messin around.