Servo questions regarding voltage an wiring

[kili]

So I was reading the paperwork that came with my Hitec 7954sh servo...
it reads like it is only compatible with 2S lipos, anybody have experience or advice? I do have a castle BEC that will be installed and I really only want to run 3S on this car without smoking the electronics....

Kinda new to the rc scene and any/all help will be appreciated from all you yeti yodas.

[gottorque]

Set the BEC to 7.4V (or a little lower), then install it. You can now safely get full power to the servo and disable the ESC's internal bec while running 3s. Keeps your servo and esc happy

[Powerman]

Why wouldnt you want to use the ESCs internal BEC? I will be upgrading to the MMP once I manage to fry the AE-3. The BEC on the MMP is adjustable from 5 to 7 volts. Regardless of Battery voltage. I see so many people in various forums adding a BEC to the MMP still. Why?

[Rxracer]

Because the bec in the MMP is only like 3 amps which is not enough for high tourqe servos.

[kili]

So will the BEC fry the MMP eventually?

[binaryterror]

Originally Posted by kili

So I was reading the paperwork that came with my Hitec 7954sh servo...
it reads like it is only compatible with 2S lipos, anybody have experience or advice? I do have a castle BEC that will be installed and I really only want to run 3S on this car without smoking the electronics....

3S is fine, but you are better with a receiver bypass to protect the receiver. This allows the ESC to handle the volts for the Receiver, but the BEC powers the servo and all is good.

Holmes Hobbies LLC

Originally Posted by Powerman

Why wouldnt you want to use the ESCs internal BEC? I will be upgrading to the MMP once I manage to fry the AE-3. The BEC on the MMP is adjustable from 5 to 7 volts. Regardless of Battery voltage. I see so many people in various forums adding a BEC to the MMP still. Why?

MMP is low amps, like 3 amps at 6volts. Thats ok, but once you turn up the input to 3S, then your amperage goes down...useless for any servo better than the stock Yeti one.

You need a BEC, and again use the Receiver Bypass.