MMM UBEC option - RC-Monster Forums

BrianG · 07.13.2008, 09:47 PM

Yes, I'll be running the ESC without the fan (hence my avatar). And yes, that will void the warranty. If you want to use the fan, you can simply plug one into the Rx since that will be powered via UBEC. As long as you use a fan, CC should honor the warranty. Don't know if they'll accept this mod though...

Yeah, I've heard a few bad things about the switch, so I replaced that too. Yup, it's a KF UBEC. They work well, and provide a real 6v output, even under load. Knowing how the CC BEC sends full battery voltage if it goes bad makes me not want to use it.

Note; even though I'm using the UBEC, the internal one is still functional but only powers the internal circuits. If using the stock fan, I would re-wire it to the Rx to prevent the possibility of blowing the internal BEC. I would rather replace a blown external UBEC than the whole ESC...

Pdelcast · 07.14.2008, 05:57 PM

Quote:

Originally Posted by BrianG

Knowing how the CC BEC sends full battery voltage if it goes bad makes me not want to use it.

You do know that ALL switching BECs have the same issue -- if the output FET fails, it sends full voltage to the output.

It's inherent in the design of a step down (buck) dc-dc converter.

Patrick

BrianG · 07.14.2008, 06:22 PM

Quote:

Originally Posted by Pdelcast

You do know that ALL switching BECs have the same issue -- if the output FET fails, it sends full voltage to the output.

It's inherent in the design of a step down (buck) dc-dc converter.

Patrick

That is true, but for some reason, the others have some circuit integrated into the IC to help prevent that (or at least reduce the chances). Usually, when they go, they just stop working.

Pdelcast · 07.14.2008, 06:28 PM

Quote:

Originally Posted by BrianG

That is true, but for some reason, the others have some circuit integrated into the IC to help prevent that (or at least reduce the chances). Usually, when they go, they just stop working.

Hmmm, not that I know of. I've seen many many UBECs die myself, and put full voltage out.

Any BEC that uses an external FET (pretty much anything over 2 amps) has the same possibility for full voltage output type failure as the Castle BEC.