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Old 08-01-2010, 10:59 PM   #1
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Default is using a 3S lipo (11.1v) on starter box safe?

well, just a s the title says... I plan to use a 3s turnigy 25c 4000mah lipo with an old starter box I have. That's 11.1 volts, a bit less than the 12v that it says the motor requires.
Would I run the risk of ruining the lipo or the motor doing this?

The starter box is quite small so using just one lipo would simplify things...
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Old 08-02-2010, 02:43 AM   #2
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Most starter boxes are designed to run on 2 6-cell stick packs which total 14.4V, so a 3S lipo would actually be underpowered a bit.
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Old 08-02-2010, 05:56 AM   #3
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Quote:
Originally Posted by Rufus2000 View Post
well, just a s the title says... I plan to use a 3s turnigy 25c 4000mah lipo with an old starter box I have. That's 11.1 volts, a bit less than the 12v that it says the motor requires.
Would I run the risk of ruining the lipo or the motor doing this?
Actually, a 3S lipo when charged will be 12.6v, 11.1v is the 'nominal' voltage which doesn't mean a lot, its mostly just a reference.

Most using lipo for starter box use a 4S, so you'd be underpowered. You will have to watch the voltage since in a starter box, there is nothing to prevent you from overdischarging the lipo and possibly runing it. It something you just have to be aware of and make sure the voltage doesn't drop below 9v (3S) or 12v (4S).

If the engines you're starting are pretty easy to get started, 3S might be plenty, but if you're got one thats hard to get started, you'll miss the extra voltage of not having 4S in the box.
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Old 08-02-2010, 11:58 AM   #4
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thanks for your replies guys.
I'm thinking of using one of those little lipo alarms to keep the voltage in check. I was just worried that the bigger voltage or amp requirements of the starter motor would strain the lipo and make it puff.
I'll be starting rtr motors and not likely the high compression ones so hopefully it will work.
Its 4000mah so I wonder if that's good or I should just get a 4s with higher mah...
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Old 08-02-2010, 12:48 PM   #5
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FWIW, starter box lipos are usually 2100-2200mah like this one -

http://www.amainhobbies.com/product_...k-2100mAh-148V


Good idea with the low voltage alarm.....
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Old 08-02-2010, 11:02 PM   #6
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well, its a small starter box which I kind of like it since it seems easyto transport. it's this one:

http://www.dynamiterc.com/Products/D...ProdID=DYN5625

got it for 30 bucks!, just one of the plastics at the top is missing and the top surface is scratched, otherwise seems to work fine.
I think I heard you could polish the top somehow and end up with a nice flat matte finish, it's stainless steel apparently.

The lipo I have is sized just like a 6cell nicd pack, just slightly wider. I think it'll fit fine, perhaps I'll use velcro or some battery straps to hold it in there.
The lipo alarm is nice, it does have an led which tells you the status, and if its low enough the alarm sounds.
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