running 5S

[jworm49]

I have been thinking about running my IM31 on 5S because I don't trust the stock ESC and motor on 6S. I have heard of people doing this but I'm not sure how to go about it. The tec support guys at Horizon Hobby told me that I can't hook up a 2S and a 3S pack in series. I know I have seen posts from people saying they have done this. So what I'm wondering is if people are running 5S how are they doing it?

[lenny]

Hear some links with lots of info.
http://www.tjinguytech.com/
http://www.rcgroups.com/forums/showpost.php?p=17907405&postcount=3

[Heaving Earth]

Sure ya can, just use same batteries of different cell count.
Ex. 5000mah 40c 2s
5000mah 40c 3s

[jworm49]

That was what I was thinking too and that is the configuration of batteries that I have. It's just the guys at Horizon told me that I cant do it.

[jworm49]

I had a bad experience already at the hobby shop where I took them My ESC to have deans plugs soldered onto it. They ended up putting one of the plugs on backwards so when I hooked up the batteries nothing happened of course and the wires got very hot. I took the esc back and they re soldered the plug on the right way but when I tried to hook up the esc to make sure is everything was ok I plugged in he 3S battery and everything was fine but when I hooked up the 2S it sparked and burnt the terminals. Long story short I'm on my second ESC and not sure if trying to use a 3S pack and a 2S pack caused the problem or if it was because the esc had been damaged due to the reversed wires.

[jworm49]

thanks lenny I will look at this when I have some time.

[lenny]

It sound like they changed the plug on your esc instead of fixing the 3s cell plug the right way,
So now your 2s cell plug is reverse now.
Some of those guys at the lhs have not got a clue what they are doing,
Learn to solder it is not hard to do.
Also you should ditch the deans plugs and get 5.5 bullets for all you connections in the setup,
The deans and the stock 3mm plugs are a weak link in the setup.

[jworm49]

Lenny does it make sense to you though that the battery and esc terminals would have arced the way it did after having hooked up a battery with the polarity reversed? Could that have damaged the ESC to the point where a battery would spark as soon as it was plugged in?

[lenny]

Not sure what you have going on there at this point,
All connections spark.
The higher the voltage the bigger the spark from the caps on the esc to let you know it is working good,
Can you post some pictures or a video of what you are seeing and going on with the plugs.
Also that stock esc works on 4s and above to 6s so they say,
But I am not sure if it will work on just a 2s pack or just a 3s pack ether.
The low volt may be kicking in with those low volts.

[iop65]

capacitators don't like reverse polarity!
don't know if your esc has reverse polarity protection so you should check the caps for swelling or bursting

like lenny said; you always will get sparks and about 5s they will get noticable, it's normal

[BHChieftain]

Hi JWorm49,
Also, at 5S you should definitely get rid of the deans connectors and use 5.5mm bullet connectors-- this also removes the harness which adds a bunch of resistance.
Chief

[jworm49]

Thanks for the input guys! Chief forgive me I'm not familiar with the bullet connectors other than on the motor leads but I will look into it. Lenny sorry the short version is I took the boat to my LHS where I bought it to have deans plugs put on the esc because I bought so batteries on line that cam wired with them. The got the polarity wrong on one plug but I didn't figure that out until I hooked up batteries to it and the other lug as normal. I took it back and they reversed the plug for me I wanted to make sure everything was working so I hooked up a 3S to the plug that had been reversed to start with but was no fixed. Then I hooked a 2S to the other plug and wham huge spark resulting in scorched deans plug on the esc and nasty welded looking deans plug on the batt. So I'm wondering if the esc being bad due to the polarity being reversed the day before could have caused this or is it because I was using a 3S and a 2S instead of either 2 2S or 2 3S batteries. I was never intending to use just one 2S or one 3S sorry for the confusion and thank you again.

[Heaving Earth]

Dude what a mess. Can you post pics ov what you got going on? It sounds like you're Lhs may not be the best place to take your stuff.

[jworm49]

Sorry HE my bad at the moment the boat is back to stock as they ordered me a new ESC. Only thing I did was get some no wire EC3 to deans adaptors for the batteries that I bought.

[lenny]

So you had a 5s dead short with the 2s and 3s hooked togeter in series with the deans plugs,
Well that sucks.
All because of your LHS ignorance,
They are lucky you did not get hurt and file a lawsuit for being ass holes.

[jworm49]

very true I'm just glad they took care of it but now you can see why I'm nervous about hooking up a 2S and 3S pack again. Plus I can't help wonder why Horizon customer service would have said that it can't be done.

[lenny]

Hear some info to read and learn about lipos and stuff,
This way you will know more than they think they know.

http://www.tjinguytech.com/
http://www.rcgroups.com/forums/showpost.php?p=17907405&postcount=3
http://www.offshoreelectrics.com/info.php
http://forums.offshoreelectrics.com/showthread.php?271-Ideas-on-Building-a-Reliable-BL-System-by-ReddyWatts.

[jworm49]

wow lot of info thanks man!

[lenny]

Post some pictures when you can,
They will help us help you see things better.
Video's are good to help you get the boat running at is best,
And they should be nice long straight run left to right passes to see how it is riding.
When it is running wet that is not good for the setup,
But when it is running air out then the setup will run better and cooler to.
And it will look like it is just hovering over the water as it flies by you.

[jworm49]

thanks man I'm not sure what pics to post because it's all stock now. But here is vid of it running stock prop 4S timing set to high.
http://www.youtube.com/watch?v=qGDRhKB3WY8

[iop65]

reduce the timing to the default settings when going to 5s!

[jworm49]

I will I was planning on it.

[jworm49]

just an idea I had for keeping the motor leads a little cooler and hopefully from melting to each other any more. 104955

[lenny]

Hi,
Need some better pictures to see what you have there in the hull.
Also with the cells in place like RTR it,
The video looked pretty good from what I could see of it.
It did look a little to loose and may blow over on 5s,
But the added weight from the cell may help it to stay planted in the water.
Are those connector 5.5 from motor to esc ?

[jworm49]

No those are stock connectors. The video was with the drive height adjusted all the way down and the batteries moved all the way back. 104956

[lenny]

Have you checked the temp on everything ?
If so what are they after a run ?
Pictures of the hardware to try and see the where the setting are at.
Also a better picture of the stuff tube and flex to motor coupler,
It look like it may be to tight of a gap there.
And that will add drag to the setup witch = more heat and less run time and speeds.
You should reverse the water lines,
Cold water coming in to the low nipple and hot water exiting out the top nipple.
Than exiting out the hull,
That will give you a lot better cooling when you need it.

[jworm49]

my rudder mount is jacked up from a running over another boat. Also I have a S&B X642 on the way. I have only checked temps by touching the ESC motor and motor leads and they are always warm but not hot to the touch same with the batteries. As for the water lines I have never heard that I'll have to give it a try why would it be better cooling though?104963104965104966

[lenny]

You should have a gap as thick as the flex at the strut and prop drive dog,
I think you can just move that prop dog back a little to get more gap there.
It looks tight to me.
Also your turn fins could be turned back more,
They do not need to be in the water when going straight.
And when you do turn than they will still do their job, But not add drag in the straights.

Something like this.
104980104981104982104983104984

[jworm49]

there is a gap though not as big as you are suggesting As for the fins I will adjust them I had no idea how to place them and had seen pics of them this way and honestly just copies it.

[jworm49]

I'm hoping the X642 makes a noticeable difference because the boat is too slow on 4S.

[lenny]

What gps speeds are you getting with it now ?

[jworm49]

ok I can see the difference.

[jworm49]

I have not used a GPS on it don't have one it just feels pretty tame so long as the water is calm.

[Cinnabun]

I would properly set the boat up before looking at more voltage. My revolts on 4s rock out with the right prop and set up.

[jworm49]

I agree and that's what I'm trying to do other than the prop I'm not sure what to do though

[Cinnabun]

Lenny gave you good ideas to start. turn fins need to be out of the water when going straight. Strut height and prop angle have a huge effect. A video of it running on smoother water would be a huge help.

[jworm49]

I'll have to try to get some better vids

[iop65]

when i was using mine on 5s stock i moved the esc next to the lipo's

it was not running wet enough(was unstable at the higher speeds) ,was easier to get the balance right when that heavy esc is more to the front (i don't like using trimtabs or big negative angles)

it's also better for the cooling because you can get a straight line from the esc to the motor inlet (i used 4-7 mm tubing, makes a big difference in flow)

and:change the connectors on that esc-lipo because like this it is very uneffective(is going to get hot on 5s),use some ec5 or some bullets (then you can also ditch the harnass)

you can cut about 10mm from the turnfins without them loosing much effect

[jworm49]

so it would seem pro boat got almost nothing right in this thing?

[kuau]

Quick question.
Going 5S in parallel on my V2 stock ESC and motor, also using a X442 prop
Upgrading all connectors to 5.5mm and 10ga wire.
Thinking about ordering my LIPOS from dinogy and was wondering what maH to get
4000 5000 6000 maH packs ?
How much difference would there be in runtime ?
Thanks