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Old 02-08-2019, 06:00 AM
  #6  
billdelong
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Originally Posted by TimF View Post
the 3s (11.1 volt) will NOT give you more run time. The higher voltage will increase top speed, not give longer runtime. My experience has been tat 3 cell batteries have a shorter run time than a 2 cell batter with the same MHa rating
This is not a complete statement to be accurate.... you want to calculate the "WattHours" , you can't compare same mAh without taking voltage into consideration, you also need to run comparable KV ratings to get the same power draw for each respective setup in order to compare apples to apples.

In the testing I have done with my TEKNO SCT410.1

3S - 4000mAh = 50.4Wh ---> 3200KV motor + 16T pinion
2S - 6000mAh = 50.4Wh ---> 4800KV motor + 16T pinion

Both systems offered nearly identical performance with presumably equal power draw and equal capacity, however the 3S setup offered significantly better efficiency with temps averaging 20 lower than the 2S setup and I would easily get a minute longer run time on 3S in this configuration. Another benefit to running 3S is that the packs would tend to last at least a year before they needed to be replaced, my 2S packs would only last about 6 months.

Another thing I have noticed is that the higher the C rating, the longer my packs would last... I found that it was more cost effective to invest in 100C packs that will age 2-3 times longer than 30C packs.

Although I prefer the 3S configuration, I have been forced to run 2S due to ROAR restrictions for the class and running in several ROAR sanctioned regional events over the years and have settled on a 4300KV motor being the optimal limit for 2S in keeping my temps in acceptable range.

Last edited by billdelong; 02-08-2019 at 06:30 AM.
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