10s setups

[David Kingston]

I dont usually post much here but i thought i might get some responce since there are heaps of people with different setups...

Im currently looking into some 10s setups.
I run a twin SGX-2 80-90 rigger with 1527/1ys also tried 1527/1.5ds
5s each motor, 40/160s for ESC's

It hammers. Initial props were the 1657's stock but now i run 1462 - 4.75inch cup and H30s with 5inch cup and its nuts.

My issue is that the rules in AUS might change and therefore my 5s each motor is not legal to run as its not a voltage of 37volts for 10s...

So im asking - who has run 2 motors of a single 10s pack?
Im looking at 1527's since thats what my motor mounts are made up for but i can make new ones to suit other diameter motors.

I need to be able to pull 60+ mm props to get the bum of the rigger out of the water. I can run smaller props but it goes better with larger ones cause thats what the boat was designed for. What ever i choose to setup the boat with it must make the 1500m oval (just short of the mile) At current my setup does make the distance without killing the cells. Nothing else gets warm, packs are 130-140 max, and im left with 35-40% in them at the end. Half mill and 5 laps. I need to park the boat after the race or things will burn. I have not attempted to do 6 laps. I know i could do it with what is left in the cells but there is no need. Unless i jump the start.

Thoughts people.
Cheers Dave

[David Kingston]

Here is a youtube link to it...

http://www.youtube.com/watch?v=5M4hSr5gppU

This was taken in september last year.
1527/1.5ds 5s each motor and 1657's stock.

Yeah some might have seen it on Rum Runner (Im hacking though the course cause the straight is 70m long there and im running longer straight to get a more accurate on the larger oval. Besides it was extremely rough out the back straight)

Any motor thoughts folks

Dave

[tth]

You should try Neu 1527/1.5y's on 10s. They are some HOGS on 10s. Your setup would be classified as 5s2p here in the states.....not sure about your neck of the woods tho.

[RaceMechaniX]

Dave,

I am a bit confused by the rules. So instead of running a 5S2P set-up you want to switch to a 10S1P set-up with both motors feeding off a common pack? Are you running in an open class or some defined class?


If you currently can't make 6 laps on 5S2P, you are not going to change the power draw by switching to 10S1P. Sounds like you need to scale back on the motors or add more capacity. Can you reduce the capacity of each pack to allow for a 10S per motor? Give us some guidlelines on installation and rules so we can propose alternatives.

I have seen twin set-ups running off a single pack, but the pack was usually 10-14S and usually 2P. The occasional 1P set-up was usually a play set-up or a serious short burst SAW set-up.

[David Kingston]

I would make 6 laps with this setup, but have never tried.
I know that the 130-140degF cell temp is getting up there for 5 1/2 laps so not wanting to push that little bit more especially when testing. If i was asked to complete the course after a race then year i guess i would just throttle right back to 1/3 and not draw heaps from the cells. The ESC wont suffer from that small amount of part throttle.

Yes the rule here in Aus are different.

EA - 4s - 600grams
EB - 5-6s 900 grams
EC 7-10s 1500 grams
(150grams per cell as a guide)

People are saying that the boat is technically a 5s/2p setup. Fair enough. But i have to push an extra motor, esc and prop. I would be as quick as the 10s single guys but not yet raced them so wont go into that yet. I have to invest in more $ to run this boat then a single...

Ive brought up the question to a few people before....
1527/1y on 5s - 62mm props.... (2 setups like this)
what about running a 1527/2y (625kva) and wire in my 5s packs as a 10s...
the RMP would be just under 24K each motor. Which is the same as what the 1527/1y would be on 5s. So therefore i should not be drawing anymore from the cells.
In theory i should have less amps as my volts have increased.

At current i do run about the 150cont amps. Data logged only once.


In about 2 weeks time im going to wire in 2x4s packs to 8s and prop to a 1650 size and then go do 2 laps. This should give me a good estimation on amp draw for running more volts. Even though the motors are not the desired ones to be running 8s on. But i need to test it.

Keep the suggestions coming please.

Dave

[RaceMechaniX]

Dave,

You are correct, but you still end up with the same issue of only being able to run 5-1/2 laps......

You are substituting voltage for current on a single set-up, but then you are adding a second motor to a 1P set-up and you are drawing the same amount of power. You've just gone in a circle. Sounds like a twin rigger does not fit the rules IMO.

Tyler

[David Kingston]

5 1/2 laps is all i need... Unless i jump the start.

This is a race boat - like 90% of my boats are race boats.
I dont mind if i push the cells that bit harder, cause the amount of times that im getting to run in racing (due to work at the moment) is limited so if i can play with the setup, get it right im happy - well almost.

So you think that a pair or 1527/2ys might be worth it?

Dave

[RaceMechaniX]

Sure, its worth a try. You can always depitch the props for that extra 1/2 lap to finish.

[tth]

Go for a 10s pack with around 8000 mah. You will be drawing less current with the 1y motors instead of the 1.5d's. Only real way unfortunately (expense) would be to try it. I know I know....easier said than done.

[David Kingston]

what 8000mah packs can i get that are 10s/1p
And also are 1500grams or less.

Thats the other issue.
Hence we are really limited here to 5500 hyperions as the largest capacity
Ill i run are hyperions.
Use to run polyRC cells but they were only 25c 6000s and now there are better C rating cells out there...

Im not really killing the cells with the setup here either. They get warm yeah.
Hay ive had a pair or H45's on the back. MASSIVE wheels and it was nuts but a dog in the corners. To much blade in the hub area which causes drag.
Cell temp was up a fair bit more but i would still be able to do the laps.

I dont mind grabbing some different wind motors, whats another 500bucks when this thing sits at 5k already. I just thought some people might have run 2 Neu motors off a single pack.

Still thinking.

Dave

[tth]

Check out Thunder Power RC 45c Lipo's 10s 7600mah Weight is not given.

[David Kingston]

Did a google search for the TP packs you mentioned...
MASSIVE CELLS - this was the first site that came up...

http://www.bvmjets.com/Pages/Catalog/Batteries.htm

WEll over the weight.
Plus i can tell you that the 6500 TP cells are split packs. 3250mah packs paralleled. Just ask TP themselves they also admit this.


Any how, did a bench test... 8s when wired up looping everything together does not work. It seams that one ESC over rides the other. I made up 2 y-harnesses. Hooked the cells up in series. With one y-harness on the -ve and other on the +ve of the battery leads i was able to connect the 8s to one ESC, letting it arm. Followed by the other ESC. Worked wonders cause a quick throttle blip and revs check was up there. But before it was like it was only running off 4s not 8s.

So with that sorted, i might have to look at how i wire things. There was heaps of plugs, resistance and thats never good. I think i might have to soldering on some more leads to the packs if i decide that going 10s to both motors is a good option... Just have to figure out if its worth it...

We are about to start discussing the electric rules here in Australia so lets hope that something can be sorted - i need a decision. If i cannot run my 5s each motor ill have a play with some other cells in a 10s setup.

ROCK ON

Dave

[ozzie-crawl]

i always thought if a there was a cell limit then it didn't matter if it was say 10s or 5s 2p
still the same amount of cells and capacity

[ozzie-crawl]

guess not in Australia under ampba rules http://www.ampba.asn.au/EC%20Class%20-Batt%20setup.pdf

[AlanN]

Plett 370/50/A1 on 10S1P 5000mah with schultze 40.160. Plenty fast enough and you won't need as big of a wheel as you may think. Around a 52mm dia. Been running this setup in my 1/8th scale for several years. There is also that new Plett motor that would/should work...teras?