Quark on 6S with Mega 6 pole
 

OK. I have just built an Inferno GT for a customer and I am having some huge problems!! Here is the setup:

- Quark 125
- Flight Power 6S2P 4350 EVO25
- Mega 22/30/1e 6pole
- 25/46 Gearing

First night out, 12 seconds into the run the controller blew up!!! Quark sent me another one within 4 days. Setup the new one. Now, on 4S test, it ran decent for the 5 minutes we tested it. Everything temped ok and the car did 69mph while spinning the tires the whole run. When we slapped the 6S, it thermalled almost immediately in the first pass!!:bad: It seems like there is a compatability issue with the Mega motor and the ESC.

SOOO...........

a: Anyone running this setup of motor/ESC successfully??
b: Has anyone ran a Feigao/Quark setup successfully as Quark told me to try another motor but I am afraid of blowing another controller or more......

Your gearing is most likely overdrawing the esc. The quark is a solid 5s controller, but very load sensitive on 6s. So try gearing down. It should not have any issues with the 6 pole motor, the quarks can run just about anything.

6s is most likely the problem.

I agree with linc,
Wow, if you are doing 69mph on 4s and then add more voltage you've gotta be taxing the esc. By the sound of that, it doesn't suprise me that the Quark thermalled on 6s

Yeah, that car must be geared for about 100 on 6s. May want to drop the gearing down to about 70 mph top speed, 18t? pinion maybe?

Well, the car was built for speed only! THis is a purpose built car for a max of 5-6 passes and then shut it down. I am going to gear it down and see what happens. Funny thing, you would think it would run cooler with the higher voltage??

I have heard no mention of a BEC being used.

Are you using a BEC with this? Because if you're not, it's going to fry the internal bec very quickly.

The Quark 125 amp version is capable of alot. I've ran 6S on 2 of mine without any issues using multi-pole motors.

As far as heat issues go, you're alot better off to mount it to an aluminum surface, if you have one available. Coat the underside with thermal heat sink compound, then secure it with ties or something.

A fan doesn't hurt anything either, especially if you're going into that upper realm of it's ratings.

I hope this helps.

Yep, I forgot to ask about the bec, use a ccbec if you can.

A fan and good heatsinking is a must, but it is good to test on lower gearing and them gear up until the equipment starts to overheat.

The Quark line of ESC's are not over rated. They will deliver the amperage they advertise.

The catch is the liniar Battery Eliminater Circuit they have built in, isn't capable of carrying the Receiver/Servo's when powered by more than 4S.

The internal BEC just creates soooooooo much heat. Even on 4S, by adding a Castle Creations BEC circuit, ESC temps will be reduced alot.

In other words, if you're NOT using an External BEC, the majority of the heat that you are seeing isn't necessarily coming from the Power FET's inside the speed controller. Most of the heat is coming from the internal BEC that just can't keep up.

The Castle Creations BEC is soo nice also. It gives you the option to adjust the amount of voltage supplied to the Receiver/Servos. I have mine set to 6.0 volts. This makes the Servo's stronger and faster than powering them by an ESC (5.0 volts).

Look in your Quark manual under "Opto-mod" for more information on using an external BEC.

I've been tempted to try one of the large 6 pole Mega Motors in an E maxx.

I wonder how it would do?

Like the 22/50 series? Those look like beasts!

Maybe the 22/45?

The controller is thermalling so fast mainly because of the 6-pole motor. Think about it. If 2 poles = 6 pulses per revolution, then 6 poles = 18 pulses per revolution. The ESC is working 3 times harder than usual. Add higher gearing and maximum voltage and that's pretty hard on a controller. Do you have a fan you could use on it? I think 5s with a fan would work fine.

Sorry, Yes, I am running a CCBEC. I have heard rumors that the 6S rating is not a "comfortable" rating....which makes me wonder why they would rate it at that level?? I am running the same setup with a CC 5700 motor on 4S in a 1/10 and doing 95mph very reliably which further leads me to believe the whole 6S rating rumor!! I am going to the smallest gear I have which is a 22T as I am running the 2 Speed adaptor and using LST2 2nd gears to drive the 46T spur. If I see it gets better, than I will have to order some Mod1 pinions from Mike to continue testing. I have already blown 1 controller while running it in outrunner mode and Quark immediately sent me a replacement as they said it sounded like faulty programming. I am now running in inrunner mode and it is holding up fine, but still thermalling 10-15 seconds into the run on 6S. I will be getting my Eagletree this week so I will know for sure what is going on on the next test run!!

I would agree with you, but I can't due to the following. Mega recommends only CC ESC's and they have no issues running a CC ESC that was designed to run a 2 pole motor?!? This leads me to believe that the Quark programming has alot to do with it. Worst case scenario, the guys at CC could maybe speed up the MMM a little( ugh, ugh) and I will go that route. We will see....

still...holding...breath...for...mamba...monster.. .maxx!

Could it be a timing issue? Depending upon the position of the rotor magnets relative to the stator windings, it can draw much more current when the stator is energized. I don't know which way you would try adjusting the timing to correct the problem, but it was just a thought.

There should be no difference in terms of which ESC can run however many poles. Sure, firmware has a part in it, but the ESC is still limited to firing the phases only so fast (whether it be firmware or hardware related, that limitation is still present). The more poles you have, the more phases that are in the motor, so the mork work the ESC really does have to do to create one revolution.

Mega also suggests keeping their motors under about 50,000 RPM on their motor selection tables. I'm willing to take a shot and say that this is due to their higher pole counts, and relates back to what What's Nitro was saying. That's also probably why they run just fine on a mamba ESC (the RPM that the motor spins is significantly lower than the problem setup mentioned by the OP).

I'm inclined to agree with him 100% that the number of poles coupled with the voltage it is being run on (a 6 pole motor being run at around 60,000 RPM is going to stress out the ESC, and the gearing is some nasty icing on the cake) is certainly contributing to the problem.

I have wound 12 pole outrunner motors quite high with direct to diff configuration with NO problems using the Quark 125 Monster Pro. 12 pole motors require twice the switching per revolution as a 6 pole motor does. I've wound the 12 pole motors up to around 25,000 rpm's. I don't think the Quark switching ability is the problem really.

After taking another look at your setup. You have quite the Battery configuration there. It can definately deliver. Just guessing, 220 amps continous, probably somewhere about 300 amps Burst rating.

Ok, with that being said. Mega only recommends winding their Mega 22/30/1e to around 44,000 rpms and only rates this motor up to 12 nimh cells or 4S with a current draw of 70 amps max. On 6S, it's going to spin 63492 rpms and will definately overheat very quickly even with dumptruck gearing. I can only imagine what the amp draw is doing with the tall gears, especially on take off.

I would try 5S with lower gearing, like Linc said. Then maybe, just maybe, move up to 6S, only after being comfortable with the temps you are seeing on 5S.

I deal directly with Mega as this is a test motor they sent me to test this setup. There ratings are actually underrated. When I approached them with this project, I learned that there ratings posted are based on what they thought would be the max "usable" RPM's out of the motors. They have been extremely helpful with this project!!! Also, keep in mind that those RPM numbers are unloaded. In the car, it is a different ball game. I should be receiving my Eagletree V3 tomorrow so I will know Wed. night exactly what is going on and take it from there.

The controllers themselves have a max rpm rating as the others have eluded to. What is it for the Q125? I remember the 9920 was rated ~150K rpms for a 2-pole motor. Since the Mega is 6-pole, the max rpms is going to be 1/3 of that, ie 50K rpms.

If you are trying to run a 6pole at over 60K rpms, you need to have a controller capable of ~200K rpms on a 2pole.

Also, the ET is an invaluable tool for figuring out the specs of a system. I think maybe you need to backoff the gearing and voltage and work your way up befoer trying to blow off the barn doors on the 1st run. This is an 1/8th scale car right? Really you are looking at prolly 2500W peak watts or so already on 4S if you are doing 69. You may be pulling close to 200A already. I'm not so sure that is the right controller for what you are trying to do. A MGM 22018 may be better and would run 6S more reliably as well.

Not a funny thing at all that it doesnt run cooler at a higher voltage in this setup.

There is a fatal flaw in you higher voltage runs cooler logic here....

A system designed to generate the same amount of power on 6s vs 4s will run cooler on the 6s. But if you are just leaving the motor and the gearing the same and spinning the motor 50% faster on 50% more voltage, you are generating WAY more power with the 6s setup so of course its not going to run cooler.

Say you were generating 1200watts on the 4s setup, now your generating 1800 watts or more on 6s. How could that system possibly run cooler.

In order to run cooler on higher voltage you have to choose an apropriate KV motor and gearing so you are only generating the same 1200watts as you were with the 4s system.

Get it?

I understand what you are saying. However, I design the system based on the RPM I want out of the system. That is why I am saying I am suprised of the heat issue. Pulling 60k out of a 2S and pulling 60k out of a 6S is a world of a difference in heat!! I agree with linc on the gearing issue. I am going to change it and see now that I FINALLY got my V3 in:mdr: I will keep you guys posted.

Ok, quick update. I have discovered the problem. No, it was not the gearing (thankfully)!! The problems is that the batteries have no balls!!! I lost 4.5V under load pulling 124amps. So what kept shutting down the system was the LVC!! You think that Quark would have put somewhere what the blinking lights mean..... Neverless, I am happy that I have confirmed this with Quark. I also tested another car with a 4S setup on a Feigao 2pole setup with lower gearing and got the same problem. So, I am going to double up the packs to run a higher C output on the 4S setup to confirm the problem, which hopefully will put everything back into high gear!!

DON'T DO IT LINCPIMP! DON'T DO IT.

Ummmm, Usually when you get on the Quark LVC, it acts like a stutter box. It cuts the power. The ESC completely shutting down would not be the LVC IMO.

If you over draw your packs to the LVC, the voltage should quickly come back up and enable you to run again. Maybe not at Wide Open Throttle, but It still should respond to throttle inputs instead of just shutting down.

Cough Cough. Help CC I don't think I can hold much longer!

Well, I have done some more testing. I ran 2 4S packs in parrallel to try to see if I could compensate the voltage drop and resolve the issue. I was wrong!! That did not work. The LVC still kicked in inspite of the 8500mah now available to the system. As a last resort, I am going to try a smaller motor. I am currently running a Feigao 7L in the car. Thinking about going to an XL. Any input would be appreciated!!

Your ESC is still shutting down? Did you measure the voltage with the Eagletree to ensure the voltage is staying above the 3v/cell threshold? What kind of current are you pulling?

Yes, ESC is still shutting down. I pulled max 124 amps on the single pack setup, so I would assume that doubling the amperage available should have dropped those numbers, but I guess not. I did not have my V3 with me, so I didn't get any actual numbers.

Actually, your amperage might go up a little with higher capacity packs since the voltage won't drop as much under load. But as long as the total pack Ah capacity X the C rating is greater than your current draw, you should be ok. If the pack voltage is still dropping below the 3v/cell LVC threshold, then I would say that the pack(s) aren't fulfilling their advertised specs.

That they are!! I had measured a 4.5v drop under load!! Logged in at 16v, max drop was 11.5v!! I spoke to FP about it and they told me the packs were wrong for the application. However, they told me that if I doubled the packs, it should have helped to further confirm that, but it is still doing the same!! This project has been very frustrating!!!!

How are pack temps? If they are dropping that much with ~120A current, they should be quite hot. A 4.5v drop at 120A is 540 watts! That kind of power should easily be able to be felt as heat somewhere. Granted, that's burst power, but still a heck of a lot!

If pack temps are within acceptable limits, I would start looking at contact/wire resistances. A voltage drop ANYWHERE from the battery, wires, or connectors will cause issues. An easy way to find problem areas is to feel for higher temps manually. Where it's hot means there is resistance (=v drop). So, after a run, feel various places and note higher temps.

The packs are warm after the run. The hottest location in the whole setup is where the wires come out of the ESC, and those temps are really not out of the ordinary, about 140-150.

Then, that v drop must be very momentary or you would DEFINITELY feel the heat. Ever feel even a 60w light bulb?

Have you tried decreasing the "torque selection"? It's not supposed to be used for amperage management, but if the motor isn't trying to ramp up so fast from a stop, it will by nature pull less current.

Also, what battery setting are you using? Lipo normal, lipo high, or manual?

man i wished i would have read this thread sooner so i could tell you about my setup. in my yusa w/2speed running a mega 22/45/2 i would only see 115 on my esc running 8s1p a123's. with everything the same but on 12s1p a123's, the hottest i've metered was 135 i think. may have been 133. this is using the turnigy 100amp hv controller and geared for 109mph. i'm not sure what its going because i just haven't had the opertunity to test everything out, but there looks to be room to gear up a bit more. the power i'm putting down is just simply too much with the 12cells. on my street infront of my house i have to ease into it very slowly to keep traction and simply run out of room by the time i'm at 1/4. i'm thinking you really need a larger motor to continue with this project. if my thinking is right you'll pull less amps from the larger motor simply because it doesn't have to work as hard. what are your motor's temps and after how long of running?

I am using Manual, 3v per cell.

Motor temps are about 100 until the ESC stops

i don't know what to say then because thats pretty low. must just be over working the esc with amp draw or too many poles then like whats been suggested. look into a plane esc and add mechanical breaks.