Amps with a MMM 2200kv combo?
 

What kind of amps will I see with the MMM/Neu type motor combo on 6S lipo?

I'm looking into batteries at this point and I would like to stay way on the safe side but I don't want a 16lb buggy :)

First ride will be a Hyper7 geared for ~45mph, then a ERevo geared about the same.

Info from the Castle testing would be awsome, but I'll settle for opinions from the guys here who have run a similar (6S-2200kv) rig.

Um, bump?

All these views and no input???

my guess would be 70-80 amps

azjc, thanks for the first post :) you've won a lovely new home furnishing... hehehehe JK

70-80 amps continuous is where the bar is set, anyone else? Peaks?

I think you will see higher amps than that - you are looking at spinning the motor >45k rpm with a 6S setup and a 2200kv motor - you're pinion will have to be very small ~11T.

I would say to go for a 1650kv Neu motor and you have a much happier setup on 6S. You could go for the Neu 3900 6S packs and the weight won't be too bad.

Personally I am going to be getting a 1512/3.5d (1500kv) motor with a 6S TP2600 pack geared at 15/46 to shoot for just about 40mph. I'll be able to gear up to 17/46 for ~45mph. I've been aiming to try a few setup where I am balancing the motor/servo side of the buggy with the lipos. The runtime is obviously less but the car tracks perfectly straight during hard accelerations and braking rather than pulling to one side - obviously this depends on where you'll run it, but I am mostly in parking lots and the veering to the side is a real pain on asphalt, i don't think it would be as bad on grass (more overall grip) or dirt (less grip more slide).

hmm... im also wanting the same answers, but i want to run a123 cells. 6s or 4s2p seems like my only 2 options for weight issues. help! will i get 35-40mph (thats quick enough for me!) out of a buggy?

I would guess that amp draw would be around 85 amps. That is not an average, or max, but more of a battery guideline. I would say that a fp 3700 25c 6s pack would work fine and still be reasonably light. Motor kv is a bit much, will this be a 1515 or 1512? For a 1512 2200kv on 6s lipo in a buggy you may be able to step down to a smaller 6s pack.

I run a medusa 36/60/1500 in a hyper8 on 6s lipo. I use a pair of fp 2170 3s lipos in series for 6s. They work fine, and I use 14/46 gearing on that buggy. Plenty of speeds and power, and decent runtimes too.

Thanks linc, that was just along the lines of the info I was hoping to get. I should hve just PM'd you, since you do own like every rig in every combination hahaha. What kind of run times do you get out of your 2170's? I'm not racing yet, just bashing, but I keep up a hard pace.

I can't comment on the buggy setups but for the revo I can tell you that the 1Y will pull peaks of around 125A, constant of 60A-80A depending on gearing and running on high friction surface like tall grass or mud and considerably lower amps on asphalt or hard pack dirt.

If you are only looking for speeds around 45 then I suggest getting a lower kv motor. That way you can run a reasonable size pinion gear (16-17t) and smaller capacity packs to keep weight down.

I run a 1Y in my revo on 5s 5Ah pack geared for 45mph and get runtimes of 12 -18 minutes depending on how hard I run.

for 45 mph i wouldn't pick either that motor or 6S;

the 1Y can draw 180A on 5S if it's geared for more speed. It's one hungry motor.

Untill castle launched it, i wouldn't advice anyone to use that 2200Kv motor on 6S. It can do 200A peaks, if it's geared for serious speed.

For 45 mph, i would go for 5S and a lower KV motor. You don't need the full potential of either the motor or the amount of cells.

I am working on owning everything! In any case I do need to pick up a few neu motors, but their prices have kept me away. I understand that they are the best, and most likely worth it too.

I have not had a chance to fun the buggy to the lvc, but I expect 20mins or maybe a little more. I need to scare up some better tires, and I just got the body painted up for it. If I have time and the weather is good I will give it a full run and report some data in the thread I have for it.

Thats interesting, my 8xl is far more power hungry then my 1Y both in peaks and average current used. I have never logged it though the few times I've geared higher then 16/38 on 5s (which is faster then needed most of the time) so I'll have to do so now. The odd thing is that when I ran the 1Y on 4s it seemed slow and under powered especially when trying to gear for more then 30 - 35mph.

the 2200 kv would be more than the kv of the 8XL. and the Neu would have more torque.

Mike takes peaks of 180A on his 1Y on 5S.

Perhaps there is something wrong with the KV of your Neu and is it mislabeled? it's quite a beast on 5S.

The kv of my neu appears to be correct as the rpms are correct for any given voltage so it's not mislabeled.

According to my MGM controller I see peaks of 185A on 5s but my eagletree v3 150A logger consistently reports only 125A peaks. Is there any chance that Mikes numbers came from an MGM controller? This has really got me curious now since there is such a large difference in readings between similar setups.

The spec sheet that came with my motor shows 1200-1500W continuous, 2700W@ 20secs 110A@ 20secs at max voltage 25v.

On 5s I pull around 2Kw peaks which I figured was in the ballpark based on the spec sheet. If I was pulling 180A that would push me up to 3.3Kw which is almost another 2hp. If that is where I should be do you think I should send the motor in to be checked?

I can tell you that my 1515/2.5d will pull peaks of 150+ amps on 6s in my 10.2 lb. RTR revo. I have to imagine that the 1y will pull 180-200 like Serum said. Maybe a little less in a buggy, but not alot less.

perhaps your batteries simple don't deliver more power to begin with.

They have got their limits. The measurements as made by Mike are done with an eagletree as well, so i guess he uses better batteries.. :)

You could contact either MGM or eagletree about this difference. What resolution are you using to record on your eagltree? Perhaps the MGM is more sensitive, since it records larger currents. Or it's completely off..

If your 1y is turning at the right KV, it would make sense if your 8XL isn't an 8XL.? the KV of the neu is higher, it has got more torque, yet the 8XL feels/is more powerful according to your statements. I can't find a logical reason for this.

just throw your eagletree in the 8XL vehicle and you'll see what is going on?

I thought I'd jump in and note that in my experience, bashing seems to draw more amps than racing and is harder on the setup. It really does depend on the driving though.

However, for me, while racing I am very smooth with the throttle, rolling on and such and always trying to put the power to the ground and not let any go to waste (wheel spin).

When bashing, I'll punch it just because I can and just because if the truck wheelies/flips or spins out it doesn't really matter. And for that, I get like 10 minutes bashing now while I get a good 15+ on the track.

Maybe the 8xl rotor demagged. This will raise the rpm, amp draw and the temperatures considerably. I don't know what temps you are getting, but if your motor is overheating uncontrollably, a demagged rotor is likely the case.

My batteries do not hold voltage as well as they should but still manage about 3.3vps @ 170A with normal temps... even so would that effect the current the motor required?

As for the 8xl it is the correct kv and has what I consider to be normal temps of 150f but it will pull 170A peaks which is more then my 1Y pulls.

I guess I'll have to borrow an amp meter so I can try to verify if I'm getting accurate readings from the eagletree and the MGM.

I dont know how the winds of the 2 motors compare to each oth
er but it is possible that there is fewer winds in the 8XL thus drawing more ampage

3.3volts per cell on 170A, these cells are VERY good. never heard these high numbers before, what cells are you using?

on 5S, that's 3000 watts. that's incredible.

On 6S, a little birdie confirmed the very same numbers to me. This is really great news, as it means a 6S1P A123 setup will be just about perfect for it. It might push the cells a bit, but still are in their range. This also means you don't have to have huge monster lipos to drive it. It seems we are getting back to selecting for runtime, rather than current capability in terms of MAh.

This also means that a 6S1P A123 setup in a 1/8th scale buggy will just about put the MMM at its full potential. That will be a nice, light setup, which would just kill on the track. I've got my 6S flat pack already made up :)

Sleeb

My apologies Serum those numbers are wrong and I wish they were that high. :whistle:

The correct figures are 3.3vpc @ 120A and 3.05vpc @ 170A.

The packs used are a FP 5s 25c 5Ah and a pair of TP 2s 25c 4.9Ah bricks. The cells perform with in 10% across all packs with the TP bricks consistently averaging slightly lower consistently then the 5s pack. I say that the numbers are low since FP claims their cells hold 3.6v at a 25c discharge rate (which is somewhat optimistic I'm sure).