5s vs 6s

With my BL Revo project I am planning on using a Neu motor, I am considering the 1515/1y (2200kv) with a 5s lipopack and the 1515/2.5d (1700kv) and a 6s lipo pack, I am planning on using the MMM esc or the MGM16018......any comments would be welcomed

[suicideneil]

The 5s option will be fast and solid, the 6s option will be solid with slightly longer run times and slightly reduced speed. Either option would be awesome, but I favour the MMM esc when its released due to the lvc issues several people are reporting with the MGMS.

[lutach]

With the 6S lipos and lower Kv motor you will have more torque. If you gear it right, you will actually use less AMPs and get about the same speed as a 5S lipos set up.

[rschoi_75]

both sound great to me.

With all other things being held equal:
5s + 1515/1Y:
- expected rpm @ 18.5v = 40,700
- battery is cheaper,
- will run slightly warmer (but not hot),
- has slightly less efficiency, and run time. Which you may or may not notice, depending on how critical you are.

6s + 1515/2.5D:
- exp rpm @ 22.2v = 37,740
- more expensive battery (you could always buy another ma 8000mah lipos and wire your existing one in series, so maybe not).
- will run slightly cooler, be more efficient, more run time.

echo.... echo... echo....

[lutach]

Originally Posted by rschoi_75

both sound great to me.

With all other things being held equal:
5s + 1515/1Y:
- expected rpm @ 18.5v = 40,700
- battery is cheaper,
- will run slightly warmer (but not hot),
- has slightly less efficiency, and run time. Which you may or may not notice, depending on how critical you are.

6s + 1515/2.5D:
- exp rpm @ 22.2v = 37,740
- more expensive battery (you could always buy another ma 8000mah lipos and wire your existing one in series, so maybe not).
- will run slightly cooler, be more efficient, more run time.

echo.... echo... echo....

Here is some more info:

1515/1Y, 2200Kv, 7-25 volts and 110A* (Good batteries are expensive)
1515/2.5D, 1700Kv, 7-35 volts and 80A* (I ran 22.2 volts for 23 minutes using 2200mAh 3S packs)

(*30 sec. at max. voltage. Otherwise, = Watts/your voltage).

[Haldir]

lutach,

What kind of car were you running for 23 min.? Thanks.

[Just go Play]

Here is a graph during a test run yesterday of the 1515 1Y 5s in my revo. I have one of the MGM's that kicks in a bit early either for LVC or over current protection but it does not seem to be consistent like many others problems were. In any case this should give you a better idea what you could expect from the motor.



BTW: Temps have never been anywhere near high enough to be of any concern, the 1Y runs very cool on 5s.

[lutach]

Originally Posted by Haldir

lutach,

What kind of car were you running for 23 min.? Thanks.

My Ofna MBX buggy (AKA Pikes Peak look for a brief moment). Here is the thread of my lipos: http://www.rc-monster.com/forum/showthread.php?t=7776. I'm still testing them.

[starscream]

Originally Posted by Haldir

lutach,

What kind of car were you running for 23 min.? Thanks.

I think it was an RC18T

The most I ever got from ~22v 2200's was around 16 min under racing conditions

Originally Posted by Just go Play

Here is a graph during a test run yesterday of the 1515 1Y 5s in my revo. I have one of the MGM's that kicks in a bit early either for LVC or over current protection but it does not seem to be consistent like many others problems were. In any case this should give you a better idea what you could expect from the motor.



BTW: Temps have never been anywhere near high enough to be of any concern, the 1Y runs very cool on 5s.

have you ever tried a 6 cell with your 1515/1y

[lutach]

Originally Posted by starscream

I think it was an RC18T

The most I ever got from ~22v 2200's was around 16 min under racing conditions

I wish I could fit the 2200 in my 18th scale. I did run on a soccer field and the grass was a little high. You can see from the graph that I had several high spikes.

[Just go Play]

Originally Posted by azjc

have you ever tried a 6 cell with your 1515/1y

I don't have any 6s packs and I don't think the 3s packs I have would be able to hold their voltage under load.

For myself running 6s with this motor in my revo would only be good for speed runs. As it is with 5s it will reach @ 45 mph which is more then fast enough for most places I can run and it feels like it will take another 1-2 teeth on the pinion easily.