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Old 11-20-2009, 11:09 PM   #1
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Default 75 Watts too low??

Will the AMP draw on a 11.1v mamba max powering 2 10T pullers in bullies be too much for a 75amp connector??

Looking at bullet connectors for the esc and dig switch. For the motor and battery connections. I need to go as small as possible. CC 5.5mm bullets are too big for my application. CC 4mm bullets are perfect size. Problem is, the 5.5's are rated at 150 amps, the 4mm rated at 75 amps.
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Old 11-20-2009, 11:10 PM   #2
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Quote:
Originally Posted by Ripperfi View Post
Will the AMP draw on a 11.1v mamba max powering 2 10T pullers in bullies be too much for a 75amp connector??

Looking at bullet connectors for the esc and dig switch. For the motor and battery connections. I need to go as small as possible. CC 5.5mm bullets are too big for my application. CC 4mm bullets are perfect size. Problem is, the 5.5's are rated at 150 amps, the 4mm rated at 75 amps.
What's the amp rating of your battery?
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Old 11-20-2009, 11:23 PM   #3
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11.1v 30C
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Old 11-20-2009, 11:24 PM   #4
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Originally Posted by Ripperfi View Post
11.1v 30C
So 1300mah x 30C =39 amps, or 1500mah x 30C = 45 amps(I can't see if it's a 3 or a 5). That's all your battery can provide safely.

I wouldn't worry about the connectors, that pack won't last long running dual 10T puller motors.
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Old 11-20-2009, 11:33 PM   #5
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Yea its 1500. 45 Amps? Thats it? And I guess motor draw doesnt matter if the battery can only put out max 45 amps. Lol I was way off in my thinking. So, all good with 75 amp connectors all the way around. Thats great news. Thanks for the quick answer Tanis. Could you do that fancy math one more time and tell me the max battery I could use with 75Amp connectors?

Just thought of another thing, If I was to double the mah to 3000, would it then put out 90 amps? So if my math is correct, the biggest battery I could run with 75amp connectors would 2500mah 30c. Is that right?

Last edited by Ripperfi; 11-20-2009 at 11:42 PM.
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Old 11-20-2009, 11:41 PM   #6
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2500 mAH at 30c rate

2.5 x 30 = 75 amps

OR

1800 mAH at 40c (for example)

1.8 x 40 = 72 amps

And yes, a 3000 mAH pack would double your amp rate.
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Old 11-20-2009, 11:41 PM   #7
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Quote:
Originally Posted by Ripperfi View Post
Yea its 1500. 45 Amps? Thats it? And I guess motor draw doesnt matter if the battery can only put out max 45 amps. Lol I was way off in my thinking. So, all good with 75 amp connectors all the way around. Thats great news. Thanks for the quick answer Tanis. Could you do that fancy math one more time and tell me the max battery I could use with 75Amp connectors?

Just thought of another thing, If I was to double the mah to 3000, would it then put out 90 amps?
It's not how much the battery can provide, it's how much the motors and servo will pull. The way to figure it, is to multiply your mah rating by the "C" rating, so yes, a 3000mah 30C pack will be capable of providing 90 amps safely. The "C" rating should also be labeled by Constant and Burst "C" ratings, for example 20C constant 40C burst(usually for 5-10 seconds at a time). When planning a pack, you want to make sure it can provide the draw the motors and servo will pull without exceeding the "C" rating for a long and happy pack life
If you are pulling more than the pack can handle, it will either swell up, or not last very many cycles.

Last edited by Tanis; 11-20-2009 at 11:44 PM.
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Old 11-20-2009, 11:44 PM   #8
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Great answers, thank you both.
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