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Old 09-02-2010, 06:04 PM   #1
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Default How important is C rating for sedan racing?

Is 100 amps enough(in my mind i think it would be plenty)? Gonna be running tc5r. tekin rs pro, novak 10.5, rubber. Just trying to figure out what lipos i need.
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Old 09-02-2010, 06:16 PM   #2
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Is 100 amps enough(in my mind i think it would be plenty)? Gonna be running tc5r. tekin rs pro, novak 10.5, rubber. Just trying to figure out what lipos i need.
Average voltage and Low IR are what's really needed, but you don't get those #s like you used to with Nimh. Typically the higher rated C packs also have better voltage which is why you see many with them, but every once in a while there is a low C pack that has a lot of punch, so yeah, uhm get some thunderpowers and hope for the best, lol.
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Old 09-02-2010, 07:40 PM   #3
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Just about any packs rated 30C or better are fine. There really isn't any standardized test to truly measure continuous current. They're mostly theoretical "marketing" numbers. For example, if a 5000 mAh battery rated at 50C really had that 50C load on it, most likely the wires, connector, and / or solder job would melt.

After a full charge, run your TC for 6 minutes. Re-charge the battery, making note of the amount of mAh it takes to fully charge the pack. Multiply by 10, and that's your average current draw. A 17.5 foam tire TC was using 2200 - 2500 mAh in 6 minutes, for an average current draw of 22-25 Amps, or less than 5C. Granted, peak draw was a lot higher (around 70A, according to a Novak Sentry data logger), but even that is only 14C. Most packs are rated at 2x their C rating for burst current (like around a 10 second "pull"). Again, not even close.
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Old 09-02-2010, 08:08 PM   #4
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Just about any packs rated 30C or better are fine. There really isn't any standardized test to truly measure continuous current. They're mostly theoretical "marketing" numbers. For example, if a 5000 mAh battery rated at 50C really had that 50C load on it, most likely the wires, connector, and / or solder job would melt.

After a full charge, run your TC for 6 minutes. Re-charge the battery, making note of the amount of mAh it takes to fully charge the pack. Multiply by 10, and that's your average current draw. A 17.5 foam tire TC was using 2200 - 2500 mAh in 6 minutes, for an average current draw of 22-25 Amps, or less than 5C. Granted, peak draw was a lot higher (around 70A, according to a Novak Sentry data logger), but even that is only 14C. Most packs are rated at 2x their C rating for burst current (like around a 10 second "pull"). Again, not even close.
Thanks man. I like seeing numbers.
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