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Old Dec 22, 2012, 02:09 PM
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Should I be concerned the motor is only rated
4S
Max Current: 43A
Max Power630W


Edit
I think I will wait for the CS 10 blade to come back in stock. In reading back through this thread it seems that the
Turnigy L2855-2300 is recommended on 5S. True?
Even though the specs say
Voltage: 14.8v (4s)
Max Current: 26A
Max Power: 450W
??
Must hold up ok if others are using it eh?
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Old Dec 22, 2012, 10:08 PM
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Those fans are Freewing I am pretty sure, and they are totally fine.

Those L2855's can all do 900W fine, and by 1000w they are under a bit excess duress.
So it will be fine.
I used to fly my Meteor (5S L2855-2300kv) at WOT pretty much all flight - just because it looks nicer to have a jet-like speed, LOL. But the batteries were not happy.... and I also know the motor, on the test bench, gets quite hot at long term WOT, (overly hot!) so it will be similar in the plane.... but a bit lower power/heat than on the bench becuase of airflow restriction reducing its ability ro run at full power when in a plane anyway, but still would be running it at a level higher than 'good for long life'.
Though.... they are very cheap motors and if one fries... put in another! hehe
I have not fried one on 4S or 5S ever, so far. But none of them are any good for 6S.... eg the 2100kv, even though you can use 6S on 2200kv or so - it has to be a higher power level motor to cope with it.
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Old Dec 22, 2012, 10:17 PM
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Guess my editing was done while you were posting.
Sounds like I have a plan!
CS10
L2855-2300kv
5S 4000mah
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Old Dec 22, 2012, 10:19 PM
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Same thing.... they are all the exact same motor, BUT the windings are different.
In such a series of motors they are truly ALL capable of the same POWER. eg 900W.
But lower KV version use thinner windings so their max current level drops, but their voltage capability rises.

So there are those TWO aspects that matter in a motor. The Max atts..... 900W across them all. Then their individual Current (Amps) ability. But generally, if one can use 50Amps, they all can anyway. I am sure the lower kv ones would be under a bit mor duress, but seem to still be acceptable levels.
HobbyKing list 'rubbish' numbers......
What they most often do is test a motor on some cell count, eg 3S 11.1v, record the Amps, then post that it was "11.1V 25A 300W"... as if that is the max specs. But they were really just one case of what they tested. Totally useless numbers....
So in general you can do a lot mreo than they state - but they do list correct numbers in some cases. So you really need to know a bit about motors to guesstimate what it will be able to do... and find out more accurately whern you test one!

But anyway..... these L2855's will do 900W fine.

Max current, I would say keep it under 55A area generally.
Ex: 5S 18.5v is 49A for 900W
At 4S 14.8V that is 61A to be 900W (P = VI Watts = Volts x Amps)

So to run at 900W on 4S, which 900W is fine for the motor in power terms, is 61Amps whcih is NOT totally fine in Amps terms for it!
Thus you need to check the 'whole picture' of your setup situation, to know what will work... or last... versus 'bad for it'.
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Old Dec 22, 2012, 10:25 PM
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Note, that will give a "pretty good speed".... nothing amazing.
Still a nice fast enough jet.
And very cheap to do!

Above that comes 1000W or so systems.
Such as:
- Lander CS10 alloy on 6S
- CS10 with CyclonePower 2200kv on 6S
- CS10 2500kv on 5S... like a Leopard, HK MAD, CP motor - all above average, stronger than L2855's

Most of those cases are $72 to $90 range. And also need better batteries.
But power/speed costs money! LOL

Meanwhile, the CS10 L2855-2300kv for 5S use is just $30 !!
I used Zippy 5S 3000mAH 20C batteries for ages... just $20 each! But they are not really up to it. You need 30C for that setup, to have a bit more power but also batteries having an easier life.
I also have some Zippy 5S 4000mAH 20C and 40C, but I have not tried those in the Meteor. But use a pair in the Dynam Me-262 which uses that same motor combo. Those batteries do it 'easy' in that, so they should be fine in the Meteor too. The 40C is a bit more powerful a result, and also cooler batteries - but the 20C are OK. I think the 20C's were $34 approx.
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Old Dec 22, 2012, 10:40 PM
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Quote:
Originally Posted by PeterVRC View Post
Note, that will give a "pretty good speed".... nothing amazing.
Still a nice fast enough jet.
And very cheap to do!
AND the nice sounding WHOOOOOOSH!
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Old Dec 23, 2012, 12:25 AM
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Anyone use this retract successfully??
http://www.hobbyking.com/hobbyking/s...dProduct=17538

I've used the larger ones in the past which appear strong enough, but are so big they dont fit flush with the wing. Will this smaller suffice??
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Old Dec 23, 2012, 02:33 AM
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Originally Posted by TheCure View Post
Anyone use this retract successfully??
http://www.hobbyking.com/hobbyking/s...dProduct=17538

I've used the larger ones in the past which appear strong enough, but are so big they dont fit flush with the wing. Will this smaller suffice??
I use those in my 70mm mirage 4000 from FMS, havent skipped a beat so far, but I would suggest graceful landings for longevity ( we have a paved runway from being a closed airport) as my meteor is heavier than it.
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Old Dec 23, 2012, 03:55 AM
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I have those in my Meteor... but you want the Metal Trunion version really. They are much better... for a fraction more cost.
And I have sprung oleos, which you pretty well need if you want it to last long term... especially on grass! I take off from a cricket pitch, but land on the oval's grass. And it is fine doing that.

Metal trunion version of that retract:
http://www.hobbyking.com/hobbyking/s..._Trunnion.html

Oleo set:
http://www.hobbyking.com/hobbyking/s...Strut_Set.html
The oleos are a bit costly, but they are excellent and there isn't much else you could get to do the job as well anyway. I did use the stock wire legs/wheels, cut down to suit, for ages, so you can certainly do that to save money!

My installation is somewhere WAY back in this thread.
The main gear is SUPER simple.... but the nose gear takes a bit more time. Not too bad if you know what you are doing from experience, but if you don't have those clues etc it can be a big project!

The main notes are:
1) Nose: Make the leg fold FORWARDS
2) Mount the retract off its "top" - the side that is away from the trunion. Change the retract mount plate to the 'full' one. Just use one large plywood 3mm or 4mm plate put up into the cut-out nose area (part of the existing open area used too). Mount the steering servo into that same single plate (pre-do it all before epoxying the plate in!).
3) Use pushrod steering - I have an outline of doing that in my Blog (most people don't do it right, but if you do know how and why then they are the best system by far!)
4) Mains - just dremel out the existing plastic mounts to take the retract unit, that works fine and is strong... and dremel out some foam for the legs and wheels to recess into.
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Old Dec 23, 2012, 06:50 PM
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Just took some static readings with my Meteor with the Lander 3580kv EDF using one of my current 4S 40-50C batteries that is getting a bit old now,
Initial peak was approx 900Watts @60Amps and settled around 865Watts @58Amps.
Then tried it again on a newer NanoTech 4S 5000mah 35-70C from another model and initial peak was approx 935Watts @ 62Amps which settled around 900Watts @60Amps.

I don't think going to 5S would be a good idea as I'm sure it will drive the motor way too hard so I might just get a couple of new 4S high C rating batteries maybe 3300mah and stick to 4S.
That 20-30 Watts that is lost at WOT with the old batteries, do you think it will make much of a difference to performance?
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Old Dec 23, 2012, 07:04 PM
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Quote:
Originally Posted by fg1972 View Post
Just took some static readings with my Meteor with the Lander 3580kv EDF using one of my current 4S 40-50C batteries that is getting a bit old now,
Initial peak was approx 900Watts @60Amps and settled around 865Watts @58Amps.
Then tried it again on a newer NanoTech 4S 5000mah 35-70C from another model and initial peak was approx 935Watts @ 62Amps which settled around 900Watts @60Amps.

I don't think going to 5S would be a good idea as I'm sure it will drive the motor way too hard so I might just get a couple of new 4S high C rating batteries maybe 3300mah and stick to 4S.
That 20-30 Watts that is lost at WOT with the old batteries, do you think it will make much of a difference to performance?
Im kinda new at this but....
900/14.8=X/18.5 X=1125 watts @ 5S
Now the question is, will your motor/esc handle that?
But then I may be off base too
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Old Dec 23, 2012, 07:24 PM
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This video shows the CS10 L2855-2300kv on 4400 65C 5 cell that I am thinking of but its more than the battery I was looking at.... 4000 30C

1120W 59.x amps and check the heat after shut down..... near 140 degrees F
Maybe I should drop to the 2100kv?

Turnigy L2855-2300kv - 5S - CS 10 Blade Test (2 min 11 sec)
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Old Dec 23, 2012, 08:38 PM
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Yeah, that is a bit much for the motor to last... but ok if you don't overstress it to long and often.
The 2100kv would survive better.
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Old Dec 23, 2012, 09:02 PM
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Originally Posted by PeterVRC View Post
Yeah, that is a bit much for the motor to last... but ok if you don't overstress it to long and often.
The 2100kv would survive better.
Same setup with 3000 20C
The battery is the limiting factor here and will puff like crazy I imagine
CS10 L2855 2300kv 5S 3000mAH 20C 50 9A 16 9V 862W 1 43Kg (0 min 40 sec)
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Old Dec 24, 2012, 12:42 AM
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I use the 3000mAH 20C in a number of planes, but the Meteor has the cleanest ducting so it runs it at teh hghest pwoer level of them all. And too much for a lot of WOT use. Though I used to fly it 80% WOT all the time..... sometimes they puffed.
You won't get the numbers as per the bench test anyway, they always drop a fair amount. I think in-plane on the 3000mAH 20C it is about 1.1Kg thrust and 50A area. But as I mentioned, the Meteor is better off with 30C in that setup.
Planes with more restrictive ducting will run it at lower power (40A to 45A areas), so those can use the 20C fine.

Meanwhile the 65C and it lower IR means more volts to the motor = more power = more heat etc. So that end result is too much for it.
Sticking to NON-Nano, plus 30C or 40C, would keep it in a workable power region instead.
You should check/tune any setups, IN-PLANE, to tailor the optimal battery for it..... de-tuning (via higher IR) can often be required to keep a setup running in a sustainable area.
But that 'tuning' is across all the items - from motor, to battery, to ESC. So that ALL of those are working in power areas they are fine with. You can put an 'overkill' ESC or motor without any real issue, but you often can't put an 'overkill' battery, or it will drive one, or both, of those other two into excessive levels.
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