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Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 4:38 am
by Aussie Joe
Aussie Joe wrote:If your jet can take the weight of the 2200mAh nanotech... do it!!! It will go faster because it will have a much much higher "C" rating allowing the voltage to stay higher for longer! :P


ergocentric wrote:even with the same C rating the available current will be higher because: available current = capacity x C rating
One thing to keep in mind about C rating is if you require a higher C rating you are getting shorter flights
1C = one hour
12C = five minutes
30C = two minutes
Who wants a two minute flight time?

I was talking about voltage and model speed, less voltage sag = more RPMs . standard 1300mah 11.1v - 25-35c Vs nanotech 2200mAh 11.1v -45-90c , the nanotech 2.2 will kick A$$, and he will have a longer flight time.

I think you may have misunderstood my above quote

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:15 am
by seedo
ergocentric wrote:
Aussie Joe wrote:If your jet can take the weight of the 2200mAh nanotech... do it!!! It will go faster because it will have a much much higher "C" rating allowing the voltage to stay higher for longer! :P


even with the same C rating the available current will be higher because: available current = capacity x C rating
One thing to keep in mind about C rating is if you require a higher C rating you are getting shorter flights
1C = one hour
12C = five minutes
30C = two minutes
Who wants a two minute flight time?



ok am confused now, should i get a battery with a low C rate so my jet flight last longer? and what about gliders? cause i always pick the C high rates.

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:35 am
by seedo
So which battery i should get?
this is my plane dimensions:

length 970mm
wing span 632mm
Flying Weight 520g

also i would like to mention i get 540g of thrust from my EDF unit

Image

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 8:40 am
by Aussie Joe
Nice jet you have,
Allways get the highest "C" rateing your budget will allow , if its in stock.
Upgrading to 2200mAh 45-90c nanotech the weight will increase by 85 grams, can your jet take a extra 85 grams?
You will have a extra 152.5 amps to play with,... please use it in moderation to much fun can let the magic smoke out.
BTW a amp/wattmeter is a exellent tool to have if your going to be into electric models for a long time.

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 9:28 am
by seedo
yes i do have a wattmeter i have the HK-010.

ok then i will start surgery today and mod the jet and check connectors, but what i will do with the 2 pack of the 1300mAh batteries?
can i use them as FPV power supply?
this is my FPV plane anyway

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Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 5:54 pm
by Shotglass
ergocentric wrote:Who wants a two minute flight time?


people whove invested north of 1000€ in a f5b model

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:03 pm
by ergocentric

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:14 pm
by ergocentric
seedo wrote:ok am confused now, should i get a battery with a low C rate so my jet flight last longer? and what about gliders? cause i always pick the C high rates.


Sorry, no.

Please do not confuse C rating on the battery with the actual current you are using.
Battery C rating (available power) -> higher is better (more durable battery)
power used (average/peak motor current) -> lower is better (longer flight time)

Keep in mind that it is difficult to impossible to measure C rating so the manufacturer can easily tell you any number they like

So in general, 1C is the ampacity of a battery discharged in one hour, 2C is twice the current (half the time or half an hour), 60C is sixty times the current (or discharged in one minute)

Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:19 pm
by ergocentric
seedo wrote:So which battery i should get?
this is my plane dimensions:

length 970mm
wing span 632mm
Flying Weight 520g

also i would like to mention i get 540g of thrust from my EDF unit


Is this your battery (maybe with a different sticker?) what are the dimensions and actual weight

I've seen some poor reviews for those Chinese copies of Deans connectors, the heat you feel in the wires is wasted power.

edit: also:
The stock battery pulled a little over 20 amps static, I got a 5 minute flight, it needed full power for most of the flight to give a realistic jet speed, otherwise it was sluggish. I landed and the battery had one cell that had puffed, so I'll have to return that one.


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Re: my plane motor went off while flying need help!

PostPosted: Mon Nov 07, 2011 6:29 pm
by ergocentric
you will have to change the plug on your speed control and charger but this should help:

http://www.hobbyking.com/hobbyking/stor ... 87C2DFB6D1

This one is about 45mm is longer and about 50g heavier:

http://www.hobbyking.com/hobbyking/stor ... 83A89BDDAC