ive blown up my last lipo battery now and need to buy some more does anyone know were they sell the 2 cell 250mah ones that pete w found in china (that place only sells th 3 cell ones now)
thanx
josh
Lipos
Moderators: BeligerAnt, petec, administrator
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Glenn Jones
- Posts: 37
- Joined: Thu Jan 18, 2007 4:34 pm
- Location: Assen, Holland
They used to sell em at the www.rctechnics.eu site.. But they don't anymore.. There are E-tec 250 mAh lipo packs available, but I thought they only have a discharge rate of 7C..
Glenn
Glenn
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peterwaller
- Posts: 3213
- Joined: Fri Feb 15, 2002 12:00 am
- Location: Aylesbury Bucks
- Contact:
Indoor flyer do single 250 mah cells at ?3.75 each see
http://www.ekmpowershop2.com/ekmps/shop ... ductid=186
http://www.ekmpowershop2.com/ekmps/shop ... ductid=186
Etec 250 mAh 2 and 3 cell packs are still available on www.allerc.com. Its where i got my spares for Katjuscha.
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BeligerAnt
- Posts: 1872
- Joined: Wed May 15, 2002 12:00 am
- Location: Brighton
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For a 3-servo ant, 250mAh will be plenty. If you are stuck for weight you could go down to around 130mAh, which would still easily last a couple of fights.
You do need to watch the maximum discharge rating. It should be given for the battery pack, and is usually in the range 15-25C, where C is the capacity. So a 250mAh pack rated at 20C can provide a maximum current of
0.25 * 20 = 5A
You should use a pack capable of 3A to be safe with a 3-servo ant.
Also, if you are using servos, beware of over-discharging your battery pack. For a 2-cell pack, the minimum voltage is 2.5V/cell, so a total of 5V. Unfortunately your receiver and servos will work happily down to about 4V, by whigh time your battery pack will be very upset!
You can buy little voltage monitors which light an LED when the voltage drops below 5V. They only weigh a few grams and are very useful during prolonged testing or practice. In competitiions, if you need to save the weight, just recharge your batteries between fights and maybe check the voltage from time to time.
You do need to watch the maximum discharge rating. It should be given for the battery pack, and is usually in the range 15-25C, where C is the capacity. So a 250mAh pack rated at 20C can provide a maximum current of
0.25 * 20 = 5A
You should use a pack capable of 3A to be safe with a 3-servo ant.
Also, if you are using servos, beware of over-discharging your battery pack. For a 2-cell pack, the minimum voltage is 2.5V/cell, so a total of 5V. Unfortunately your receiver and servos will work happily down to about 4V, by whigh time your battery pack will be very upset!
You can buy little voltage monitors which light an LED when the voltage drops below 5V. They only weigh a few grams and are very useful during prolonged testing or practice. In competitiions, if you need to save the weight, just recharge your batteries between fights and maybe check the voltage from time to time.
Gary, Team BeligerAnt