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pinkpanda3310
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06.28.2011, 02:15 AM

I had a look at Brian's car set up guide and compared a stock e-revo geared for 45mph on 2s and 6s.

6s result was 15a, 333w average draw and 98a, 2175w burst
OMGWTFBBQ result was 45a, 378w average draw and 292a, 2453w burst

I went a step further and made my own hyperthetical using Asheck's revo as target power. Trying to assume the same driving style etc.. Average 15a on 4s = 252w average guessing 1680w burst (100a burst * 16.8)

HV setup-

Motor- Neu 1515 3D, 1360kv, 0.012ohms, 30200rpm (on 6s)
Battery- Hyperion 6s, 2200mah, 35c, 0.014ohms
Esc- MMM, 0.0003ohms

Power-

22.2v * 11.4a = 253w average
22.2v * 76a = 1687w burst

Losses-

11.4a * 11.4a * 0.0263ohms (combined resistance) = 3.4w average
76a * 76a * 0.0263ohms = 152w burst

3.4/253 = 1.34% power loss to heat average
152/1680 = 9% burst

OMGWTFBBQ set up-

Motor- Neu 1515 1D, 4100kv, 0.003ohms, 30340rpm (on 2s)
Battery- Hyperion 2s, 6500mah, 35c, 0.0021ohms
Esc- MMM, 0.0003ohms

Power-

7.4v * 34a = 252w average
7.4v * 227a = 1680w burst

Losses-

34a * 34a * 0.0054ohms (combined resistance)= 6w average
227a * 227a * 0.0054ohms = 278w burst

6w/252w = 2.4% power loss average
278w/1680w = 16.5% burst


Those 2 setups do not take into account losses from wires or voltage drop which would affect the LV setup more than HV. On top of that, the rate of temperature increase will be more on the LV setup due to higher amps which of course affect all components leading to more resistance, heat, voltage drop.

I did this for my own curiosity but figured I would post it since I took the time to work it out.
   
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