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Old Oct 10, 2012, 07:57 PM
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Originally Posted by Little-Acorn View Post
Several posters have questioned whether the stock SSS ESC (3A BEC, rated for 4 or 5 servos in the manual) can handle the SSS's six 17-gram micro servos.

In posts 12 and 13 of an older RCGroups thread, two guys measured the free-moving current and stall (blocked from moving) current of some typical medium-sized (37g to 45g) Futaba servos. They measured 60 to 105mA with zero to "light" loads, and 430 to 500mA stall current when the servos were blocked from moving. (See )

If the SSS's 17g micro servos' performance is in that ballpark (they may be less since they are smaller and lower-torque), you'd have to stall all six of them simultaneously, to reach or exceed the 3A provided by the SSS stock ESC. It's probably nearly impossible to do that (stall all six at the same time).

I think we're safe, unless the SSS's micro servos somehow draw more current than those larger Futaba servos.

Don't try this at home, you can damage a servo by blocking it from moving while giving it commands to move.
A 4S with a linear BEC is a recipe for disaster simply because of the voltage step-down to servo voltage generates far too much heat which can and will shut down the ESC. A 3S with 4 analog servos (with no binding) is the maximum or 3 digital servos . Six servos ona linear internal BEC is insanity and suggesting it is OK is absurd.
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