450 X# flies again

[murankar]

So now that I am on the hobbywing ESC on the X3 I am quite happy except one little thing, NO PWM Setting. My new esc and motor are getting way to hot for me to accept this as normal. I know on the Castle, Scorpion Motors do not run no where near this hot. Now on the Garbon things are fine. So who has some answers because I could not find any. I am on the Scorpion HK III 2520 3500 KV 3.5mm shaft. I am supposed to be 5% timing which is where I am and I need to be at 8 kHz. Supposedly the 60 amp Pro V4 is stuck at 18 kHz which is going to burn up my motor and esc.


Dont be getting the panties in a bunch. I am working the video stuff now. Its going to be a few hours.


I think I just figured out the issue. I think the gear mesh might be to tight. I dont think I have any lashing between the main gear and motor pinion. Never mind I do.

https://youtu.be/x716_3zO6RA

 

[trainrider06]

My ESC runs hot on my 500 (around 120 degrees) but on the Dominator it barely gets warm!

 

[murankar]

this is getting almost to hot to touch. I have one more theory to check tonight. Once I check that then ill know if its the ESC or the motor. One thing I forgot to add, I checked the motor bullets before I installed the motor. There is way less solder wicking on this motor. Who ever prepped my last motor for solder got carried away with stripping the coating off.

After class or at lunch I will check the soldering on the ESC that I did. I have a feeling that I did not do a 100% perfect job possibly. I have 2 more male housing to work with which mean I have 2 shots left to make this work.

 

[Smoggie]

Higher PWM generally if anything reduces motor temperature and is overall more efficient. It puts more load on the ESC but the ESC is designed for it, so it should be fine. Where I can adjust PWM I always set it to the maximum available and this has yet to cause me any problems. The Scorpion PWM advice is a bit out of date and probably based more on the limitations of their own ESC at the time rather than optimum setting for the motor.

For timing I've had good results from the Hobbywing default (15 degrees). Different ESC brands handle timing very differently so you cant automatically use the same setting for any brand.

 

[murankar]

would timing change the heat issue? or is timing more of an efficiency thing. Only thing I can think of is that I have a bad solder joint on the positive battery lead. I did not do my normal "trim off the factory tin" or add new solder that would help in the even heating of the wire while soldering.

 

[Tony]

Too much timing will put a LOT of heat in the motor. It's firing the stator before it gets to the magnet thus creating more power, but also more heat.

 

[murankar]

Would that cause the ESC to over heat also?

the 4025 on the Garbon is at 4 degrees and it runs fairly cool for my flying ability. So I will give the bullet a look over and I will see about droping the timing on the esc.

 

[Smoggie]

As a general rule lower timing does run cooler (to a point) but if you are already at 5 degrees timing then you haven't got much to reduce it by. Like I said, with my Hobbywing ESC's I run the default 15 degrees on a range of motors and they all run well with no overheating, that includes the Scorpion in my Chase 360. Scorpion motors do run pretty hot though, they are well known for it. Too low timing can also cause problems of the motor dropping out of synchronisation with the ESC when under load, but if that was happening you usually know because the motor screeches and falters.

It couldn't be something simple like the gear mesh too tight or a stiff bearing or something similar could it?

 

[murankar]

We will find out after I eat. I just re soldered the positive side of the esc, just to make sure I got a good solder joint. The backlash on the pinion ans main gear is good, just a tiny amount of play in the gear mesh. The thing that is bugging me is that my 2221-8 on this setup with a castle did not even get this hot. My last 2520 did not get this hot when I first had it on the Castle. If this is going to be the norm I got a lot to get used to. It just freaks me out.

 

[murankar]

4 degrees is still getting hot.

 

[Smoggie]

yeah, 1 degree was never going to make a significant difference. I'd try the ESC default setting (15 degrees i think)..

 

[murankar]

Let me ask this first: Would to low a setting cause overheating? If to high causes heating would to low do the same thing?

 

[Smoggie]

It's possible if the timing was too low and the motor was losing synchronisation with the ESC.

Thing is that i have a similar setup with similar HW ESC and Scorpion motor (main difference is lower Kv and 6s power) and mine runs fine, not too hot at all. I have 15 dreg timing and 30kHz PWM

 

[murankar]

So I will give the timing a shot at 15 degrees. How are you able to adjust the PWM? My program box does not offer a setting for adjusting the PWM. My program box is at version 3.2####. This is really making me want to check the Garbon. I am almost positive that I have it set to 4 degrees and this thing is running flawless.

It doesn't seem like my motor is loosing sink with the ESC. It actually sounds better now that I have all the stuff replaced that I replaced.

At lunch i decided to go for it. I did a reverse loop. Punched vertical then flipped it tail first. Next thing you know its in the sun. Yes i lost it in the sun. Tail went nuts started shaking and crap, then i started shaking and just before terra firma became an issue I managed to get it level again. Even if i would have gotten it on video the sun would have killed it anyways. Maybe tonight if this timing thing is solved.

 

[Smoggie]

Mine is the older 50A V3.. I'm guessing you have the new 60A V4?. The V4 should run cooler because it has active freewheel. I think they locked the PWM on the V4 because there isn't really any point in changing it. As I understand it as high as the ESC supports is the best setting in almost all cases.

 

[murankar]

Thats what I have been reading. That the PWM is locked out. Yes mine is the V4.

 

[murankar]

Set the timing to 15 degrees 10 degrees and 8 degrees. Nothing got the motor cooler or the esc cooler. I just checked the goby and it is at 4 degrees and 8kHz and the firmware is on the most current V3.

 

[Tony]

Get a temp gun and check the actual temp of the motor. >200ºF and you are in trouble. <200ºF and you are fine.

 

[murankar]

Well my dumb ______ forgot the multi-meter with a temp sensor at home. In fact I forgot all three multi-meters at home. The only way I can test pack voltage is with my tongue.

 

[Smoggie]

Uri, I think you said you were running 4s?.. In that case the problem might be your 3500Kv motor and/or pinion size. 3500Kv is what's recommended for 3s so if running 4s you would have to gear down quite a bit. I think the stock pinion is 12t (?) so in that case you would want to go down to a 9 or 10t pinion.

Running over-geared for your motor Kv and battery could certainly explain why it runs hot.