[buffythesaint]

From what I've learned from reading, lower # of poles= lower freqency and timing. If you have two poles(magnets), the higher switching freqency switches faster(moves the generated magnetic field) and works with two magnets. The motor tries to keep up but finds its too hard to , generating heat and perhaps slipping a pole(magnetic field passes the magnet), loss of power. If your motor has 12 poles(magnets) the higher frequency has more magnets to work with, easier on the motor(less heat) and giving a good RPM(rotating magnetic field is working better with the motor). If you make a change to your ESC and you see a rise in RPM, your doing good. If you make a change(higher timing say) and you see no increase in RPM, all you are doing is generating wasted watts and heat. RPM is everything. The ARC motors are running in the 90% efficientcy range, very similar to the Nue motors. You won't be disappointed Trevor. If anyone else has some info to add or my info is flawed, please chime in and let us know.

Trevor, here is the link on the 36mm ARC motors. Some good info.

http://www.rcgroups.com/forums/showt...ht=arc+36+75+1

Brian.

[Guest]

Thanks Brian! Im now getting a better understanding of how the poles/timming works. Going to do more testing at the feild today. Dave's bringing allll his electronic test stuff.

Trev

[Guest]

You count the poles usually by counting magnets. Lower poles generally equals lower timing. For instance my Pletty 30-10 Evo is 20 pole and requires 26 degrees of advance timing (high, or hard timing), where a 2 pole inrunner probably runs good on 0 to 5 degrees. Most all ESC's vary the timing with load, so it can be hard to predict what the real timing is they are operating at.

For instance on the CC 85 and a Pletty Evo motor (high pole outrunner) you actually have to run it in low timing because it advances the timing so much on its own while operating that running it at the high timing setting causes problems.

Running an incorrect timing will usually cause a screeching noise if its bad enough, and the esc will potentially overheat and can be damaged. Any reputable motor manufacturer should be able to tell you the timing that the motor needs to operate at.

For switching frequency, its set based on motor inductance I believe. Basically you want to run it as low as possible, more switching equals more losses, and less efficiency, so after you set your timing run the switch freq as low as you can get it and maintain good operation.

Watching the video though, I would say you don't have a problem (serious one anyway) with your timing settings. I would say your packs just don't seem to be hanging in there (what are they? history?), usually timing changes are reasonably minor to performance. Put a wattmeter on it and see what your packs do.

[buffythesaint]

Originally Posted by vettster

Thanks Brian! Im now getting a better understanding of how the poles/timming works. Going to do more testing at the feild today. Dave's bringing allll his electronic test stuff.

Trev

Keep trying different things Trevor, test, test, test. Eventually you will find a good mix. the ARC will be easy to set. I use lowest frequency, 8 and 2 degrees of timing. I did a fish scale check on my setup(Trevors way) and got 6lbs. 2ozs of pull(bat packs were 92% full). I have not opened up the cheater hole but I may have to. I'll take an inch off and try again.

[Guest]

Originally Posted by can773

You count the poles usually by counting magnets. Lower poles generally equals lower timing. For instance my Pletty 30-10 Evo is 20 pole and requires 26 degrees of advance timing (high, or hard timing), where a 2 pole inrunner probably runs good on 0 to 5 degrees. Most all ESC's vary the timing with load, so it can be hard to predict what the real timing is they are operating at.

For instance on the CC 85 and a Pletty Evo motor (high pole outrunner) you actually have to run it in low timing because it advances the timing so much on its own while operating that running it at the high timing setting causes problems.

Running an incorrect timing will usually cause a screeching noise if its bad enough, and the esc will potentially overheat and can be damaged. Any reputable motor manufacturer should be able to tell you the timing that the motor needs to operate at.

For switching frequency, its set based on motor inductance I believe. Basically you want to run it as low as possible, more switching equals more losses, and less efficiency, so after you set your timing run the switch freq as low as you can get it and maintain good operation.

Watching the video though, I would say you don't have a problem (serious one anyway) with your timing settings. I would say your packs just don't seem to be hanging in there (what are they? history?), usually timing changes are reasonably minor to performance. Put a wattmeter on it and see what your packs do.

Thanks for the detailed explaination Can773 I appriciate the help.

Today I went to the feild and Changed the timming to LOW I then pluged in the same 7s pack as before and the it started off strong and then kept dying off as in the video. So I change to my Brand New 6s pack. Exact same results. Dave was awsome enough to have brought a Brand New motor the exact same. I installed it and.... The problem still exist. No change at all. Theres only one thing left folks. Its got to be the ESC. Maybe I got a bad one. Tonight Dave comming thru as a trooper again gave me his Brand new HK 100 7s ESC to try. Ill let you guys know how it goes tommorrow night.

I should mention.. at the feild Dave ran his F-86 on the stand for a good 30sec or more with the exact same setup as mine and his didnt drop off in the slightest were mine would instantly show a noticble drop.

Thanks for the input guys! Its not a total loss. Im learning alot about an area that I wasnt to sure about.

Trev

[buffythesaint]

Trevor. When we talked last night, I should of asked if you were using some capacitor's on your ESC extension? Not sure if that would make a difference or not. If you did, can you make up another extension, without the caps and give it a try? I didn't put them on my setup. I thought the extension was not that long.

[Guest]

Yes I am using them and I had planned to do as you mentioned tonight aswell before swapping out the esc.

Thanks

[davecrash]

Originally Posted by buffythesaint

Trevor. When we talked last night, I should of asked if you were using some capacitor's on your ESC extension? Not sure if that would make a difference or not. If you did, can you make up another extension, without the caps and give it a try? I didn't put them on my setup. I thought the extension was not that long.

Trevor and I are running the almost exact same setup, The differences being mine is in a F-86 and his a F-100. the ESC Battery lines are similar in length but i don't have the extra capacitors in my battery line (which you usually need when running longer lines). I video'd that flight and it sure sounds just like the batteries were dying off so just to be sure I lent him mine and it did the same thing. They worked just fine on mine today. The only thing left here is his battery line with the extra capacitors and the ESC it's self. I gave him a HK SS 100amp 7S ESC last night to try and suggested to Trevor today that I try is ESC in my F-86 just to be certain. The only 2 things left i can think of are either a problem with the programming of the Low voltage cut off is coming in and slowing it down, Which doesn't really fit cause it should just go right to half speed or it's just a faulty ESC. Swapping it out for mine will tell us for sure. We will get him fixed up and running for Ottawa. By the way I got 6.7lbs of thrust on 7S in the F-86. I'm still flying it on the 6S though. Too much nose weight on 7S for the grass fields we run on.
My nose gear wouldn't come down on todays flight and i had to land on the tanks today, Sure glad a glassed the bottom of them for just such an ocassion.

[buffythesaint]

Any luck Trevor, on your testing?

[Guest]

Just finished. The problem is FIXED!!!

It wasnt the Capacitors. I bypassed them and no improvement. Turns out it was the Landers Aluminum Fan. It was creating an EMP and at 90% the basement lights would go out Ok ok After bypassing the capacitors, nothing else was left but the ESC. I hooked up Daves SS HK 100a ESC and pressto! it works perfectly. Only problem was that I was now down to 3.8 per cell, so Im now waiting for them to charge. I also took out that Landers fan wich is just to big to fit in there. It created to many problems so I installed the new 90mm that HK realeased last week. Sweet looking 5 bladed fan. Fits perfectly and I was now able to use the thrust tube again to tidey everthing up. With any luck. Ill be maidening again tommorrow for the 3rd time I think it is. By the way.. the nose gear improvment works awsome! Its so strong that this time I actually bent the gear instead of ripping it out. The Trailing link gears will fix that bending problem soon