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Old Jul 29, 2012, 06:51 PM
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Australia, VIC, Melbourne
Joined Nov 2006
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The reason a higher C battery COULD 'blow up' a motor is......
Any electrical/electronic device presents an Impedance to the power source. Resistance - but a dynamic one in some case, or possibly a fixed one in other cases. In motor/ciols etc it is dynamic and varies with the load it is under.
So for any given Volts source, it will draw X amps - which can vary as load does - and you could sort of say it ends up at some rough area (if you apply full power of your source to it).

If you have a weak ability battery (eg 10C) then the battery will sag under the motors demand, and then the motor will run slower and thus cooler etc too. Less output. Say the motor could draw 30Amps under the load of its use, IF it had a source that could supply that. So 3000mAH with 10C ability would just do that (tho C ratings are crap and it probably would not truly do 30Amps anwyay)
If you put a 20C, which is then capable of 60Amps supply, the motor would still only draw what it wanted by its load condition.. in this case 30Amps.
So higher C made no difference.

But the reason it COULD make a difference is that if the motor in our case (but it doesn't) would draw 70Amps if it could, but you were using a 20C battery, that could only technically do 60Amps, then if you went to higher C it would run faster and have more output... and more heat and wear.
You really need to test current (Amps) with a power meter to know what is really going on, and also test with higher C, or batteries in parallel so you get more Amp ability.

In most (95%+?) cases, if it ran OK on lower typical C (like 20C or 30C) then having more available is unlikely to matter.
But when we stress out motors in systems that run them over their specs - and a very good example is using the L2855-2100 on 6S - then going to a higher C WILL fry the motor. Because on 20C or 30C 6S (approx 4000mAH) the L2855-2100 will draw 55A area and be ok, but if you give it batteries that CAN supply more Amps (like 40C or more) then it will draw the more that it always really did want. And then it will fry over the shorter term.
All because you used a higher C battery....

So the situation matters.
But in the Meteor on 4S, that motor is easily capable of driving its load (fan in the Meteor) to the level it can to is maximum, if you give it enough current source. Which is already happily supplied by 3000mAH 20C (=60A ability). So using any higher C won't change anything in this case.

At 5S, seeing the motor is already being run over specs quite a way by then, 3000 mAH 20C (60A) and 30C (90A) seems to work fine, though a few people have had the ESC or motor blow up. So it is in that zone of nearing too much for it.... and giving it 40C could move your own system, that was working fine at 30C, to just go over that edge and blow something.

But as mentioned.. at 4S, there should not be an issue at all. The motor and ESC are operating well down in their specs area.
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Old Jul 29, 2012, 07:52 PM
no more glow models for me!!!!
iflyrc1012's Avatar
bklyn n.y.
Joined Jan 2008
881 Posts
peter,
a simple "i agree with iflyrc" would have been enough.....lol
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Old Jul 29, 2012, 07:55 PM
Gotz tha Jet Feeva!!
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United States, GA, Kennesaw
Joined Dec 2011
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Lol...some people tend to be more "enthusiastic".
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Old Jul 29, 2012, 08:22 PM
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Joined Nov 2006
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No, because his answer doesn't explain WHY. And why that could matter in another setup a person uses. So people then go and do anything just because someone said something would work, in that case (this case), and they believe it applies to all cases.
It is far better to know WHY things truly work and are ok or not. And if you learn it all, then you don't even need to ask. Plus will also then know how to optimise setups and/or make choices of upgrades.

All too often people say "It is fine to do this", and they don't even truly know but it worked in theirs. They just think they 'know' based on that one case, limited data. Which is fine IF they state that... rather than just say 'it works' and no qualification to that.
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Old Jul 29, 2012, 10:08 PM
no more glow models for me!!!!
iflyrc1012's Avatar
bklyn n.y.
Joined Jan 2008
881 Posts
Peter,
Assuming that you know more than the rest of us is pretty pompous. most people on these sites DON'T WANT TO KNOW EVERY DETAIL OF WHY..THEY SIMPLY WANT A BRIEF ANSWER TO THEIR QUESTIONS, without a long winded lecture.while i realize that you have only the best of intentions, are just trying to better inform the other readers of this thread and do have a lot of knowledge to share, you sometime come off a bit condescending...
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Old Jul 29, 2012, 10:22 PM
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USA, AZ, Buckeye
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Quote:
Originally Posted by PeterVRC View Post
No, because his answer doesn't explain WHY. And why that could matter in another setup a person uses. So people then go and do anything just because someone said something would work, in that case (this case), and they believe it applies to all cases.
It is far better to know WHY things truly work and are ok or not. And if you learn it all, then you don't even need to ask. Plus will also then know how to optimise setups and/or make choices of upgrades.

All too often people say "It is fine to do this", and they don't even truly know but it worked in theirs. They just think they 'know' based on that one case, limited data. Which is fine IF they state that... rather than just say 'it works' and no qualification to that.
Peter good response in my book. I get asked these types of questions all the time in my club and at the field. Once the theory is picked up and understood, it makes working with batteries, fans, motors and esc's alot easier....at least it did for me. So when ever someone asks, I always like to try and share the theories in laymans terms (because that's really what matters to most of us) which is how I understand them then they can make their own, better informed decisions.

Good write up.
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Old Jul 31, 2012, 08:45 AM
speeddemon
United States, TX, Whitesboro
Joined Jun 2011
138 Posts
I will say some of the HUGE replys do kill me and i sometimes get lost lol but its fine, battery's and ESC should be here tomorrow. Ill pop em in and go fly this weekend and see what happens!
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Old Aug 11, 2012, 05:08 AM
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Joined May 2010
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This jet was recommended as a first EDF.. I was also considering a hobbyking stinger 64 mm or a 64 mm t-45...does anyone think this plane would be best first edf for someone with 5 monthsmed- fast trainer flying experience... i also have 2 other EDFs on the way a 43'' wingspan vampire 70mm and a 50 mm F9F panther...I watched dozens of edf jets and like this dynam meteor quite alot..seems to be very nice stock compared to many others that have various issues...thanks PS i perferr to hand launch and belly land as i don't have a runway just a big open area 2 mins from my house...
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Old Aug 11, 2012, 09:26 AM
Fighting Gravity
bonnie9496's Avatar
Australia, WA, Perth
Joined Jan 2011
551 Posts
Quote:
Originally Posted by hate2crash View Post
This jet was recommended as a first EDF.. I was also considering a hobbyking stinger 64 mm or a 64 mm t-45...does anyone think this plane would be best first edf for someone with 5 monthsmed- fast trainer flying experience... i also have 2 other EDFs on the way a 43'' wingspan vampire 70mm and a 50 mm F9F panther...I watched dozens of edf jets and like this dynam meteor quite alot..seems to be very nice stock compared to many others that have various issues...thanks PS i perferr to hand launch and belly land as i don't have a runway just a big open area 2 mins from my house...
I have both the Meteor and a Stinger. Both great planes so you can't go wrong and both well mannered and pretty easy to fly.
The Meteor IMHO is a slightly more stable model in flight.The hand launch/belly land requirement pretty much makes it the Stinger though as the Meteor would be quite a large handful to launch. Care is needed with the Stinger though as the hand launches can be tricky until you have them perfected.
Good luck!
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Old Aug 11, 2012, 12:45 PM
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Quote:
Originally Posted by bonnie9496 View Post
I have both the Meteor and a Stinger. Both great planes so you can't go wrong and both well mannered and pretty easy to fly.
The Meteor IMHO is a slightly more stable model in flight.The hand launch/belly land requirement pretty much makes it the Stinger though as the Meteor would be quite a large handful to launch. Care is needed with the Stinger though as the hand launches can be tricky until you have them perfected.
Good luck!
It seems a lot of guys hand launch edf's that are that size...RC powers hand launches the meteor with a little under hand toss..I think it is all about form as u say...Both these jets have a lot of power in stock setups which also aid in successful hand launching..thanks... i may have to flip a coin on this one...
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Old Aug 11, 2012, 01:14 PM
no more glow models for me!!!!
iflyrc1012's Avatar
bklyn n.y.
Joined Jan 2008
881 Posts
hate2,
the meteor is one of my favorite planes to fly, but it's not a trainer. stick with the 64 mm jets you have for a season or 2, then when your good and bored flying them, move up to a 70 or 90mm jet...and a rookie handlaunching the meteor is a recipe for disaster....do you have access to a paved runway? if not then don't buy the meteor. it is better suited for rog than hand launch.....
also the meteor is a 4 cell jet... i thought you were gonna stick with 3 cells for a while?
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Old Aug 11, 2012, 01:16 PM
Life's short - Enjoy!
DeeCee 57's Avatar
Zurich, Switzerland
Joined Nov 2009
653 Posts
Quote:
hand launches the meteor with a little under hand toss
Good luck with that technique, video please

Quote:
a lot of power in stock setups
Interesting...
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Old Aug 12, 2012, 02:21 AM
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Australia, VIC, Melbourne
Joined Nov 2006
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I would be scared to hand-launch mine!! Mainly as "sometimes things go wrong" !!
But with planes/jets that are heading to near 1:1 thrust to weight ratio, they just "fly away" suprisingly easily. Hardly a toss needed at all.
Many people are hand-launching 90mm's which are a lot bigger than the Meteor! (Starmax F-16, FlyFly F-22, etc etc... ALL kinds).

I fly Mode2, so I am holding the TX in my right hand and have control of the Elev/Ail all the time, and hand-launch left handed (not the Meteor ever though). So I would expect the first time or so would be 'scarey', but very likely to find it is very easy really.
I would launch a Meteor under-hand, that is actually an easy way to hand-launch planes. 15deg to 20deg and WOT would have it fly away fine. And it would probably fly away fine even at anything up to about 45deg launch angle, beacuse of the high thrust to weight ratio. Err... on 5S that is!
Stock 4S you would need to be more 'normal', 'proper' about the hand-launch! hehe
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Old Aug 13, 2012, 04:05 AM
How close are those trees?
Goody63's Avatar
Perth, Western Australia
Joined Apr 2008
1,930 Posts
Quote:
Originally Posted by bonnie9496 View Post
I have both the Meteor and a Stinger. Both great planes so you can't go wrong and both well mannered and pretty easy to fly.
The Meteor IMHO is a slightly more stable model in flight.The hand launch/belly land requirement pretty much makes it the Stinger though as the Meteor would be quite a large handful to launch.
Good luck!
Meteor quite a large handful launch??

Oh reeeaaaalllyyy???

Depends what your running in it I guess!!

Dynam Meteor Maiden (1 min 32 sec)
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Old Aug 13, 2012, 11:49 AM
speeddemon
United States, TX, Whitesboro
Joined Jun 2011
138 Posts
5s on meteor= AWESOME! haha its amazing straight vertical on take off.. for sure getting more 5s's
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