RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   Electric General Discussion (https://www.rcuniverse.com/forum/electric-general-discussion-106/)
-   -   What does the formula tell you? (https://www.rcuniverse.com/forum/electric-general-discussion-106/11543448-what-does-formula-tell-you.html)

c130nut 06-14-2013 01:47 PM

What does the formula tell you?
I have been out of electrics for a few years and am trying to remember what a particular formula tells you. I think it was the amp rating of the battery times the C rating then divide by 1000. Like 2200*30C= 66000 > 66000/1000=66 Is this the max amps that battery can discharge or the ESC rating I need?
I just cannot remember, but I am trying to re-rig an old Great Planes Siren hotliner.

guver 06-14-2013 02:12 PM

RE: What does the formula tell you?
C means "capacity" and the number is a multiplier. It can a number of currents (amps) such as recommended charge rate , max charge rate , burst discharge rate , max constant discharge rate, ect. Most times when we use the phrase "C rate" we are describing the maximum constant discharge rate by the cell manufacturer. I think that's what you're after and those ratings many times are grossly inflated when using a pack in a plane.

For a 2.2 pack that is listed as a 20C it is then 2.2x20=44 amps.
For a 2.2 pack that is listed as a 5C it is 2.2x5=11 amps.

c130nut 06-14-2013 02:32 PM

RE: What does the formula tell you?
Ahhh... I found it...

A 2200mAh 10C battery is rated to be discharge at up to 22A (10 x 2200mA/1000) and the same size 12C battery would be good for 26.4A (12 x 2200mA/1000).


Thanks for the info! I knew I had seen it somewhere before.
Bill R.

All times are GMT -8. The time now is 10:29 AM.

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.