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Old Jun 20, 2010, 08:40 PM
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Brazil,IN
Joined May 2010
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going from 20C to 30-40C discharge 14.8 can i burn my ESC??

Hey guy's I have a Nitroplanes Airfield 70mm F-16 my batteries are the generic batteries they come with, A 14.8 2200mah 20C battery, When i finish flying the batteries are hot and puffed, I mean burn yourself hot, I had ordered a Turnigy 2200mah 30-40C battery since I was told that jets should run a higher C rating
but I just don't know for sure if there is a chance I could fry the ESC? Also I don't know the ESC rating I would assume its a 50-60 but does not say anywhere, How would I find out what the largest capacity battery I could run in it? How would I determine it?? I know size and weight increases but the other variables. Thanks a million for any replies!
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Old Jun 20, 2010, 09:20 PM
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Joensuu, Finland
Joined Mar 2002
1,480 Posts
The motor will pull as many amps as it needs. The fact that a battery is capable of supplying more does not change this. If your 20C batteries are hot and puffing, they are not capable of supplying enough amps for your motor/fan combo. You will need to measure your current draw and select the battery so that capacity times c-rating is greater than the amp draw - for example your 2200mAh 20C battery would be capable of no more than 44A (assuming that the manufacturer is honest about the numbers. I wouldn't run it above 30A). If your esc has been running reasonably cool until now, it won't be a problem with higher c-rating batteries. The only limitations for battery capacity are physical size and weight.
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Old Jun 21, 2010, 02:05 AM
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Letchworth, Great Britain (UK)
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As jkettu has said, you need to measure your amps to make sure everything is running within it's ratings.

A possible issue when you change to higher-C battery is that your present pack might have been restricting the amount of amps the motor can get so, when you change to a pack with higher C, that restriction will be gone and the motor will be able to draw what it really wants -- which might be more amps than before.

I would have expected the stock batteries to be appropriately sized for the model, so it might also be worth checking if there's anything obvious that's making them overheat, like a bad motor, or no cooling airflow.

Edit: How long are your flights? If you're getting your 20C packs too hot, then in theory you've been running at somewhere close to 20C (44A for those packs), which will only give you 3-minute flights. And have you been running the packs until there's no more power left in them? That'll cause them to heat up as they run down to dangerously low voltage.
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Old Jun 21, 2010, 09:51 AM
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Brazil,IN
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I would say flight time is around 5 minutes, Granted I don't fly at full throttle the full flight, I usually bring it in when the motor fluctuates in sound makes a weird uh un uh un sound like it was meant to do it when it runs low so you can land it, even if I fly it for say 2 minutes and bring it in the battery is still smokin' hot, Also last night after this post I was installing a my 7ch Hobbyking 2.4 system in my Airfield 70mm F-4 Phantom and I stuck that 30-40C discharge battery in it and throttled it up and it smoked the 50A ESC in a instant! SMOKED literally like a old freight train!!!! terrible and I know for a fact that it had worked with the other 20C battery so!? I have a brand new Mystery 60A ESC that I am installing tonight but I will not run that 30-40C Turnigy Battery!
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Old Jun 21, 2010, 10:14 AM
Patrick Jenkins
USA, LA, 5
Joined Dec 2006
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That is a battery suited for cruising around and throttle managment. The 2200 20C that is. I would go with a 2500 25C at the least. You may want a 30c to 35c, but I use 25C and they just get warm. For EDF, 2200s are just for 4 min flights.
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Old Jun 21, 2010, 10:22 AM
Patrick Jenkins
USA, LA, 5
Joined Dec 2006
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Quote:
Originally Posted by greenmonsta79 View Post
I would say flight time is around 5 minutes, Granted I don't fly at full throttle the full flight, I usually bring it in when the motor fluctuates in sound makes a weird uh un uh un sound like it was meant to do it when it runs low so you can land it, even if I fly it for say 2 minutes and bring it in the battery is still smokin' hot, Also last night after this post I was installing a my 7ch Hobbyking 2.4 system in my Airfield 70mm F-4 Phantom and I stuck that 30-40C discharge battery in it and throttled it up and it smoked the 50A ESC in a instant! SMOKED literally like a old freight train!!!! terrible and I know for a fact that it had worked with the other 20C battery so!? I have a brand new Mystery 60A ESC that I am installing tonight but I will not run that 30-40C Turnigy Battery!
A battery can't smoke an esc if the set up is correct. Did you have a esc that is rated for 3S and 4S batteries? Maybe you went from a 3S to a 4S or the ESC was defective.
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Old Jun 21, 2010, 11:40 AM
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USA, GA, Marietta
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Apparently you do not have a wattmeter. A wattmeter is an essential tool when setting up electrics. You have to know how much current your system is asking for so that you can properly size the ESC and battery. A $50 wattmeter will go a long way toward saving many $$$ worth of ESC's and batteries.

Glen
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Old Jun 21, 2010, 01:50 PM
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Brazil,IN
Joined May 2010
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No I have a digital multimeter it was at my shop, I swear to god the minute I plugged the 2200mah 30-40c 14.8 Turnigy battery into the ESC leads it smoked it and just seconds previously I had the battery the plane came with the generic 2200mah 20C 14.8 plugged in and it worked fine, The minute I plugged that Turnigy battery in the ESC literally Smoked (damn smell was in the house for hours!) Bad battery??????
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Old Jun 21, 2010, 01:57 PM
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Letchworth, Great Britain (UK)
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I think I read recently of a battery pack that was shipped with the plug on the wrong way round.

Are you sure your Turnigy was plugged into the ESC the right way? -- reversing the leads is about the only way I know to instantly smoke an ESC.
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Old Jun 21, 2010, 02:26 PM
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Haralson County GA. USA
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There have been cases of the main power leads being reversed on a LiPoly. There have also been cases of the balancing leads reversed.
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Old Jun 21, 2010, 02:33 PM
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Brazil,IN
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Black to Black, Red to Red, All I know for sure is the ESC went to the big ESC heaven in the sky and in a big way!!! I think when I get home tonight I will toss it. I don't feel like toasting another ESC because of a turd battery!
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Old Jun 22, 2010, 02:25 AM
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Letchworth, Great Britain (UK)
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Quote:
Originally Posted by greenmonsta79 View Post
Black to Black, Red to Red, ...
Yes, but have you checked that red is in fact the positive wire on that pack? What I read (and I think everydayflyer was talking about too) was the actual colour leads being the wrong way round, as well as the plugs
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