Bec

[EddieM41]

Curios, if you leave your battery on after a run...will it fry a Digital servo. I have had this happen twice....(reciever battery 7.4)? Forgot to disconnect.

[Xrayted]

No, that is not normal assuming the servo you are using is equipped to handle the voltage you are using. Im confused though, because you are asking about a "BEC" per the thread title, but then mentioning using a "receiver battery 7.4V" as if you are not using a BEC from the ESC, but instead using a separate 2S lipo to power the electronics, which if true is 8.4V when fully charged. Are you using an HV servo rated for that voltage if so?

Those are two different powering methods that shouldn't be used at the the same time, unless I am misunderstanding what you are saying? You need to disable the BEC power by removing the red wire from the ESC lead if really using a separate battery power source for the electronics, otherwise double powering the RX could be your issue.

Other issues can be the servo is in a bind in its installation or connection to the rudder, causing it to overheat and burn out if left powered up for long periods. The servos in ANY type of RC craft should be able to be powered up indefinitely without any issues at all for the servos

[EddieM41]

I have a 51" mono with TP 5680 with 970KV. I'm running a ZTW 300 that requires a RX pack. The pack that I am using is 7.4V, 2S. The servo that I'm using is a Power HD 40kg. Operating voltage from 6 - 8.4. Based on these statistics, there should be no problems. I accidentally left the RX battery attached all night. In the morning everything worked except the servo. I tried a new servo, and it worked just fine with RX pack fully charged.

Sorry for the confusion...it was late, and I was tired.

[Xrayted]

Yep, the servo didn't move because the 2S lipo pack was drained too low to operate it. The RX LED can power up on very low power. Mystery solved, and glad it was easy!