R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Electric On-Road (https://www.rctech.net/forum/electric-road-2/)
-   -   How important is C rating for sedan racing? (https://www.rctech.net/forum/electric-road/431310-how-important-c-rating-sedan-racing.html)

portyansky 09-02-2010 05:04 PM

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.

MikeXray 09-02-2010 05:16 PM


Originally Posted by portyansky (Post 7890994)
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.

CarbonJoe 09-02-2010 06:40 PM

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.

portyansky 09-02-2010 07:08 PM


Originally Posted by CarbonJoe (Post 7891406)
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.


All times are GMT -7. It is currently 05:06 PM.

Powered By: vBulletin v3.9.3.8
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.