Problems with kk.2.1.5 board (broken?)

Gabriel said:
Ok, so I took it out today and it flew for about 1-2 minutes before the props stopped spinning and it plummeted to the ground. I checked the battery voltage and it was at 9.9v (max is about 11.4v). The guy at the hobby store told me not to drain it past 10v, but I thought that it would fly for longer before it depleted that much, as my RC plane which the battery came with, flies for about 10-15 minutes on a single charge. So, I tried to charge it and it wouldn't charge again.........

Any idea why it won't last more than about 2 minutes?

Is there a charger that you recommend that can bring it back up to voltage from <10v?
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The battery is trash or should only be used for very low discharge applications. This is why chargers won't charge lipos that get too low. You can set your charger on NiMh or Li-ion until you bring the battery back up to 10 then switch back over to LiPo.
 
The battery is trash or should only be used for very low discharge applications. This is why chargers won't charge lipos that get too low. You can set your charger on NiMh or Li-ion until you bring the battery back up to 10 then switch back over to LiPo.
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Ok. My problem is that I don't have a charger that can switch to Li-ion or NiMh. I have the basic charger that came with my plane (http://www.horizonhobby.co.uk/aeroonline/e2eflite/e2accessories/e2chargers/e2acccharlipo_2.html). I guess I'm looking for a new charger.

What charger do you recommend that is able to do that?

Also, should I look for a better battery? Which battery do you recommend?
 
Gabriel said:
Ok. My problem is that I don't have a charger that can switch to Li-ion or NiMh. I have the basic charger that came with my plane (http://www.horizonhobby.co.uk/aeroonline/e2eflite/e2accessories/e2chargers/e2acccharlipo_2.html). I guess I'm looking for a new charger.

What charger do you recommend that is able to do that?

Also, should I look for a better battery? Which battery do you recommend?
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What ESCs are you using? You might need either LVC enabled (don't do this if you are going very far from your takeoff) or have a voltage buzzer. What size battery are you using now?



http://www.hobbyking.com/hobbyking/...scharger_1_6_Cells_GENUINE_US_Warehouse_.html
 
What ESCs are you using? You might need either LVC enabled (don't do this if you are going very far from your takeoff) or have a voltage buzzer. What size battery are you using now?
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I'm using a 3s 3200mah battery. I have a voltage buzzer that came with my kk, but I don't know how to read the voltage of the battery with the kk. Also, the quad only flies for about 2 minutes before the battery dies.... Is that normal?

(I'll look into the charger that you recommended, thanks)

Do I need a bigger battery?
 
Gabriel said:
I'm using a 3s 3200mah battery. I have a voltage buzzer that came with my kk, but I don't know how to read the voltage of the battery with the kk. Also, the quad only flies for about 2 minutes before the battery dies.... Is that normal?

(I'll look into the charger that you recommended, thanks)

Do I need a bigger battery?
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2 minutes? Hahaha, list your specs and we can look for a battery to give you a little better flights times.
 
2 minutes? Hahaha, list your specs and we can look for a battery to give you a little better flights times.
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Parts:
(I don't know the weight of the quad, as I don't have a scale)
 
Gabriel said:
Parts:
(I don't know the weight of the quad, as I don't have a scale)
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Take a look at this battery, it is about the same weight as many 3 Ah ones. I have one and really like it haha.
 
Take a look at this battery, it is about the same weight as many 3 Ah ones. I have one and really like it haha.
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When I get the battery and charger (I ordered them last night), what is the minimum voltage that I should discharge my battery to?

Also, the battery that you recommended is 5.2A, and the charger says that it'll charge up to 5A. They will work together, right? Or won't they?

(^Pretty stupid of me to order them before asking this XD)
 
Gabriel said:
When I get the battery and charger (I ordered them last night), what is the minimum voltage that I should discharge my battery to?

Also, the battery that you recommended is 5.2A, and the charger says that it'll charge up to 5A. They will work together, right? Or won't they?

(^Pretty stupid of me to order them before asking this XD)
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Be sure you are not confusing Ah with A.
Ah= Amp hours, it is how much the battery will hold
A = amps, it is the measurement of current
 
Be sure you are not confusing Ah with A.
Ah= Amp hours, it is how much the battery will hold
A = amps, it is the measurement of current
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Ok. Thanks. I will get back to you when I receive my battery and charger.
 
Ok, where the charger says "EFLC3010 2-3S LiPo Balancing Charger, 0.5-3A" it means that it will only charge at a maximum rate of 3 Amps, This means that you can do 1C charging up to 3000 mAh (3Ah), any battery over 3000mAh will recieve a lower charge rate.

This only means that it will take a little bit longer to charge the battery, a 5200 mAh battery charging at 5200 mA will take 1.00 hour to charge, add in a 20% efficiency loss and you have 1.20 hours. Now if you can only charge it at 3000mA it will take 1.73 hours, or 2.08 hours assuming 20% efficiency loss.
 
Ok, where the charger says "EFLC3010 2-3S LiPo Balancing Charger, 0.5-3A" it means that it will only charge at a maximum rate of 3 Amps, This means that you can do 1C charging up to 3000 mAh (3Ah), any battery over 3000mAh will recieve a lower charge rate.
This only means that it will take a little bit longer to charge the battery, a 5200 mAh battery charging at 5200 mA will take 1.00 hour to charge, add in a 20% efficiency loss and you have 1.20 hours. Now if you can only charge it at 3000mA it will take 1.73 hours, or 2.08 hours assuming 20% efficiency loss.
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Ok. I bought the charger that you recommended earlier, so that won't be a problem.

At what voltage should I charge the 5200mAh battery so that I don't overdischarge it, but so that I still get optimal flight time?
 
Gabriel said:
Ok. I bought the charger that you recommended earlier, so that won't be a problem.

At what voltage should I charge the 5200mAh battery so that I don't overdischarge it, but so that I still get optimal flight time?
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I like to discharge my 3S batteries to 11.1.
 
Gabriel said:
That Battery's max capacity is 11.1......
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Hahaha, no that is the storage voltage, if you charge it to full it will be 12 something (~12.6v). You can discharge to 3.3v PER CELL fairly safely and still use around 95% or your total capacity. I suggested 11.1 (3.7v per cell) as it is much easier on your battery and will allow your battery to last longer.
 
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Hahaha, no that is the storage voltage, if you charge it to full it will be 12 something (~12.6v). You can discharge to 3.3v PER CELL fairly safely and still use around 95% or your total capacity. I suggested 11.1 (3.7v per cell) as it is much easier on your battery and will allow your battery to last longer.
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Ok.
 
Hahaha, no that is the storage voltage, if you charge it to full it will be 12 something (~12.6v). You can discharge to 3.3v PER CELL fairly safely and still use around 95% or your total capacity. I suggested 11.1 (3.7v per cell) as it is much easier on your battery and will allow your battery to last longer.
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I was just thinking, is my motor + esc + prop setup draining the battery? I've heard somewhere that that can drain the battery, but I don't know if that's true... :rolleyes:
 
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