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dannylightning
08-26-2010, 05:00 PM
wanting to get some turnigy 2200 packs. i want the one that will give me the longest flight times.

FR4-Pilot
08-26-2010, 05:09 PM
Higher C packs can be discharged at a higher rate, meaning thay can discharge faster than lower C packs. The voltage will stay higher throughout the discharge, but the end will come sooner. That's one of the trade-offs.

So actually, higher mAh batteries with lower C ratings could last longer under certain conditions.

An analogy: Gas engine, fuel tanks and fuel lines. Think of "mAh" as fuel tank capacity. Think of "C" as fuel line diameter. If the engine wants a lot of fuel, and large fuel line can deliver, then the tank will empty faster than if a smaller fuel line was being used.

-John

dannylightning
08-26-2010, 05:10 PM
Higher C packs can be discharged at a higher rate, meaning that can discharge faster than lower C packs. The voltage will stay higher throughout the discharge, but the end will come sooner. That's one of the trade-offs.

so i am better off getting a 20c pack right?? i dont want one that is gonna wear out really fast.


also will the connector work, i know the 400 uses a ec3 connection to hook up the battery

i see it says the charge plug is a Charge Plug: JST-XH i would guess that is the plug you use to connect the battery to the heli but not sure.

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9805

SYMAWD
08-26-2010, 05:19 PM
The higher the C the more efficient the power will get to the motor. The guy at the LHS explained it to me like this. A 20c pack is like pouring water through the top of a water bottle, not a very steady, fast or efficient stream. A 35c pack is like cutting the top of the water bottle off, so more comes out at once. The pouring water equals battery power. The higher the C the more power to the motor, but because it is discharging faster you will have slightly shorter flight times.

FR4-Pilot
08-26-2010, 05:21 PM
It depends on how you fly or discharge the pack. If you fly gently around you'll get the longest run time. If you punch it hard you'll get less. Just like a car - hard starts and stops will use gas quicker than slower starts and stops.

It's just that with a 20C pack the voltage will drop (RPMs drop too) when you punch it because the battery can't supply the higher current being requested from it - it only lets so many mAh out at a time. With a 30C pack the voltage stays higher (RPMs stay higher too) when you punch it because it has no problem delivering the extra current and will "run out" quicker if you punch it a lot.

It's a trade-off:


Lower C packs = potentially longer run time but lower performance



Higher C packs = potentially shorter run time but higher performance


If you have a higher C pack but fly gently you'll get just as much run time as a lower C pack (of the same mAh rating) - no more, no less.

-John

dannylightning
08-26-2010, 05:24 PM
The higher the C the more efficient the power will get to the motor. The guy at the LHS explained it to me like this. A 20c pack is like pouring water through the top of a water bottle, not a very steady, fast or efficient stream. A 35c pack is like cutting the top of the water bottle off, so more comes out at once. The pouring water equals battery power. The higher the C the more power to the motor, but because it is discharging faster you will have slightly shorter flight times.

i get it, i thought he ment it would go bad faster cus it was discharging at a faster rate.

ill probably go with the 20 c batterys than, one guy said he was getting 12 min flight times with a 20c 2200 turnigy battery, that would be great. i dont expect to get those kind of times but if i do that would be killer.

my flight times have definitely cut down after adding new electronics. i can get about 5 min and 30 seconds and than i notice a loss in power. i was getting 7 min easily before i upgraded.

Capt.Chip
08-26-2010, 05:30 PM
The Turnigy LiPos come with the right balance plug, but, the main battery leads are Deans T plugs. You can either cut 'em off and solder on EC3s or make up a Deans to EC3 jumper. ;)
Hey Danny, do you have a pic off your GY520 install? I just ordered one today. Thanks!

FR4-Pilot
08-26-2010, 05:32 PM
He's right about the rate thing - higher charge and discharge rates will consume/kill any battery sooner than slower rates. Just another trade off.

In general, a given battery subjected to high charge and discharge rates will die much sooner than if it were charged & discharged at lower rates.

Dazhim
08-26-2010, 05:41 PM
i get it, i thought he ment it would go bad faster cus it was discharging at a faster rate.

ill probably go with the 20 c batterys than, one guy said he was getting 12 min flight times with a 20c 2200 turnigy battery, that would be great. i dont expect to get those kind of times but if i do that would be killer.

my flight times have definitely cut down after adding new electronics. I can get about 5 min and 30 seconds and than i notice a loss in power. I was getting 7 min easily before i upgraded.
Danny to use another car analogy. its no different then putting bigger injectors in a car. or a bigger camshaft.. better performance always cost more at the pump lol. don't get the 20c I have the turn 2200 25-35c and I am gonna try the bigger ones then that i can live with 5 min flight times.. lol after I do 5 min I need to land to recompose hahahhaha
not to mention you are already talking bout flips n rolls those eat batteries because number 1 you would b flying in IU. 100% throttle now the way the pack is explained to me.. was that the pack had a 25c discharge with a 35c burst .. which is only good for a few seconds at most it will not run @ 35c until it is demanded.. which is what cuts your times every time you roll it flip it those are burst when you demand the most from the packs, and aftermarket gear.. If you were going to fly slow n smooth.. no inverted flying or anything.. or just learning to hover but you are passing that stage

dannylightning
08-26-2010, 05:49 PM
Hey Danny, do you have a pic off your GY520 install? I just ordered one today. Thanks!

no i dont, ordered the damn ting from the local hobby shop 2 weeks ago and its not come in yet. he said it would be here on monday, it is now Thursday and i am starting to get mad, but i guess i got it for extremely cheep compared to the price i see on it every where else so i cant coplain too much. maybe it is worth waiting for. took my friend 3 weeks to get the stuff her ordered from there.

the guy at the hobby shop always hooks me up so i guess i should just let this slide, it should be here any day now.

dannylightning
08-26-2010, 05:51 PM
Danny to use another car analogy. its no different then putting bigger injectors in a car. or a bigger camshaft.. better performance always cost more at the pump lol. don't get the 20c I have the turn 2200 25-35c and I am gonna try the bigger ones then that i can live with 5 min flight times.. lol after I do 5 min I need to land to recompose hahahhaha
not to mention you are already talking bout flips n rolls those eat batteries because number 1 you would b flying in IU. 100% throttle now the way the pack is explained to me.. was that the pack had a 25c discharge with a 35c burst .. which is only good for a few seconds at most it will not run @ 35c until it is demanded.. which is what cuts your times every time you roll it flip it those are burst when you demand the most from the packs, and aftermarket gear.. If you were going to fly slow n smooth.. no inverted flying or anything.. or just learning to hover but you are passing that stage

well its looks like most of my flling is going to be some what slow, with some flips throw in at least till i can find a bigger area, the stock 20c batter sure seems to pack a punch when i give it full throttle stick. that thing shoots up in to the air so fast its not even funny, going by that i think a 20 c would probably be fine. i do want the longest flight times i can get.

SYMAWD
08-26-2010, 07:29 PM
what about ordering a few 20Cs and then get at least one 35C and then you can see what you like best.

Daddy B
08-26-2010, 07:50 PM
I have to disagree with the advice you are being given, DannyL.

The C rating multiplied times your Ah rating equals the constant amperage the battery can discharge. Most give a burst rating as well, for example:

A 20C battery (with 30C burst) at 2.2Ah (2200mAh) will constantly discharge at 44A and 66A for a short duration (burst). Your stock ESC is only 25A, and you aren't running it as max current all of the time.

Current, or Amperage doesn't force its way into a motor or ESC, it is drawn based on the internal resistance of the ESC and motor. So, you could put a 45C battery on a heli, but if the motor and ESC only draws 20A constant current and 35A peak, you just threw your money away. A higher C rated battery won't make the motor spin faster, only higher voltage will. A better ESC with a lower internal resistance (better FETs) will give you a noticeable improvement over stock, and probably run cooler.

If you have a battery with too low of a C-rating (10C), it will overheat because the amperage draw from the motor and ESC will be more than the battery can discharge, due to internal resistance in the battery.

I would buy 20C and save a sackful of money.

Dazhim
08-26-2010, 08:37 PM
Daddy B I DO NOT disagree with anything you said .. but I do use a aftermarket ESC and I put a draw on my ESC .., because after half stick I'm at 80% power and my upgrades no I have not put a amp meter to it .. I just know I do more than the stock was set up for . So yes I see the difference .. I know Danny a lil bit and he will b upgrading the ESC shortly..

Daddy B
08-26-2010, 10:02 PM
Daddy B I DO NOT disagree with anything you said .. but I do use a aftermarket ESC and I put a draw on my ESC .., because after half stick I'm at 80% power and my upgrades no I have not put a amp meter to it .. I just know I do more than the stock was set up for . So yes I see the difference .. I know Danny a lil bit and he will b upgrading the ESC shortly..

Yep, a better ESC definitely draws more current. Now that I think of it, I did see a difference between the stock battery and the eflite 30C battery.

I guess I was thinking more of the case of the 2200 mAh batteries, which should be more than able to handle the draw of any 400 or 450 helicopter setup. Then again, you don't know if Turnigy and Zippy accurately rate their batteries!

FR4-Pilot
08-26-2010, 10:14 PM
A higher C rating battery doesn't make the blades spin any faster - but it helps keep the voltage from dropping during punches, which in turn keeps the RPMs from dropping as well.

And no, current doesn't force it's way into the motor or ESC. If the ESC and motor "ask" for more current (ie. during a punch) then a higher C battery can deliver it without causing the voltage (thus RPMs) to drop. Continued "asking" for more current - and getting it - will simply result in a quicker discharge of the battery.

-John

newhelliguy
08-26-2010, 10:29 PM
If your motor can ask for more than the battery can deliver it is hard on the battery. Higher C rating is less likely to get hot or puff as easy as lower C rating. Running close to or above the c rating will shorten the life and eventually cause puffing and shorten life. And what those other guys said.

dannylightning
08-27-2010, 04:22 AM
Daddy B I DO NOT disagree with anything you said .. but I do use a aftermarket ESC and I put a draw on my ESC .., because after half stick I'm at 80% power and my upgrades no I have not put a amp meter to it .. I just know I do more than the stock was set up for . So yes I see the difference .. I know Danny a lil bit and he will b upgrading the ESC shortly..


probably wont be upgrading the esc any time soon, it no longer gets hot after flying but the battery still do.

5 min flight times just wont do it for me.

20c flight times vs 30c flight times. can some one explain how much of a difference i will get in flight time between a 20 and 30

Luvmyhelis
08-27-2010, 04:49 AM
It all depends on what your motor and esc are asking for, but if you can use the extra energy the 30c battery is capable of producing such as an ICE 50 and a Scorpion 4600 and you are flying hard 3d you can pretty much knock off as much as 30% of your flight time as when you are using stock components with a 20c battery. This is very general but easier to understand.

dannylightning
08-27-2010, 08:43 AM
It all depends on what your motor and esc are asking for, but if you can use the extra energy the 30c battery is capable of producing such as an ICE 50 and a Scorpion 4600 and you are flying hard 3d you can pretty much knock off as much as 30% of your flight time as when you are using stock components with a 20c battery. This is very general but easier to understand.

any one ever use the 2450 lipo on their 400, probably too big and heavy but if not these are the ones i want.

http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10274&Product_Name=Turnigy_2450mAh_3S_30C_Lipo_Pack

also any one know where you can get a xt60 to ec3 adapter, the only one i found are the female xt60 to the the male ec3 i need it to be the other way around.

i think these are the one i need. http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10258&Product_Name=Male_EC3_%3C-%3E_Female_XT60_%283pcs/bag%29

SYMAWD
08-27-2010, 09:02 AM
danny you need these I believe
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=10259

dannylightning
08-27-2010, 09:47 AM
danny you need these I believe
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=10259

the connector on my battery is the male, so i would need a female ec3, and i think the new battery has , OMG:arggg::arggg::arggg: u know i may not be the brightest person in the world,

i am looking at the connector on my E flite battery not the connector on the ESC.

u got me thinking, i was like wait no that cant be. i pick up a battery and examine it while i was typing this. and realize i am a idiot lol.

thank, i probably would have ordered the wrong ones.

Mixmaster Pilot
08-27-2010, 10:02 AM
:lol:

That's alright. The two times I have removed my flybar paddles, I've put them back on so they both face the same way (as in both leading edges face the front, so one is really facing backwards).

I only notice after the a few hours when the loctite has set :Slap

SYMAWD
08-27-2010, 10:04 AM
the connector on my battery is the male, so i would need a female ec3, and i think the new battery has , OMG:arggg::arggg::arggg: u know i may not be the brightest person in the world,

i am looking at the connector on my E flite battery not the connector on the ESC.

u got me thinking, i was like wait no that cant be. i pick up a battery and examine it while i was typing this. and realize i am a idiot lol.

thank, i probably would have ordered the wrong ones.

Trust me it took me a while to figure out if I linked the right ones. Females are for the battery and Males are for the ESC. So that Male XT60 is acting like your ESC but then comes out with an EC3 Female for your male EC3 ESC connector.

I hope what I just said was right because we have male JSTs on our SR batteries and female JSTs on our SR ESC.

I just looked at the 400 battery on line and yes I did link the right ones.

dannylightning
08-27-2010, 10:08 AM
Trust me it took me a while to figure out if I linked the right ones. Females are for the battery and Males are for the ESC. So that Male XT60 is acting like your ESC but then comes out with an EC3 Female for your male EC3 ESC connector.

I hope what I just said was right because we have male JSTs on our SR batteries and female JSTs on our SR ESC.


well now i just need to know if i can run the 2450 or not. and i will be ready to place my order. i really hope so, i want the longest flight time possible. 5 or 6 min just seems so short.