trex 600L combo external BEC

[Hawkboy000]

Why can't we be friends? [emoji56]

[Luvmyhelis]

Originally Posted by Hawkboy000

Why can't we be friends? [emoji56]

It isn't the wires. It is the actual fbl servo bus that gets damaged. Art at Skookum and others emphatically agree that two separate wires are needed to introduce higher amp draw systems current into the Fbl controllers. We do have examples, many of them at the manufacturer level. That prove the bus fails at 10a+. So I run a separate bec running off 3s flight packs myself. With dual leads going into my fbl controller. And yes, I use telemetry and Skookum logging. I saw direct voltage dips off a variety of higher end 2s flight packs on my logs and dozens of others from other pilots. Just avoid most esc based bec's as this is a major fail point as documented by MKS. Any good bec running off a good 3s pack will give you everything you need.

I have never heard of wires melting outside shorts, but have tons of info on fbl bus failures under loads.

There is no reason to be disrespectful. Opinions are what this forum is filled with. They vary due to personal experience. I am blessed to be in the middle of a lot of them.

[FiLazer88]

Woah guys, had no idea this was such a controversial subject.......lets just remember we are here to help each other out, no? Thank you all for your advice. Based on what a lot of you were saying, I wired a 2s (had an ec3 connector on it so I got an adapter for ecs to 2 JR leads) to the two lower ports on the gpro (battery and sbus ports). It looks like my servos all had serial numbers on the back of them, does this mean I got lucky and avoided the bad batch that I have heard so many stories about? Will power the thing up tonight and see how it all works.

[Smoggie]

Originally Posted by FiLazer88

Woah guys, had no idea this was such a controversial subject......

It's not really the subject, some people can create an argument over anything!

Sounds like you have a good setup I hope everything goes smoothly following power up!

[nabl74]

You can use a BEC together with a guard like the scorpion guard or optiguard. The guard is wired up in series with your bec ( I think downstream) and is charged off your main battery pack maintains 5v supply, if the main feed from the bec drops below 5v (ie bec or loss of main power, the guard kicks in and keeps your receiver / gyro powered (for one flight).

Basically the benefits are (imo)

a) lighter overall weight (depending on bec and guard weight)
b) only one battery pack to charge (main batteries), less likely to run into battery charge problems, receiver batteries can fail, and also less mucking around charging up 2 battery setup.
c) redundancy where your bec fails, the guard will have sufficient charge for one flight to keep all surfaces / gyro / receiver functioning if you loose power.

Im just about to received my 600L dominator and based on the above thinking the bec / guard approach.

unless someone can convince me its definitely something I should reconsider.

[IrvingWashington]

The problem is that when the bec fails its more likely doing it by giving full battery voltage direct to receiver than giving 0 voltage. So im not sure that every bec has this behaviour but I've seen a lot of reports of CC doing it. The guard wont save your electronics for the over voltage.

IMHO a good 2s pack will never ever fail. With a 2s 1200mah you can do 8 flights, i only do 4 flights and then recharge it. And its very very light.

[nabl74]

thankyou

[Smoggie]

Originally Posted by IrvingWashington

The problem is that when the bec fails its more likely doing it by giving full battery voltage direct to receiver than giving 0 voltage.

So what evidence do you have to support that?

Switching voltage regulators as found in BECs are very common place. Your ESC uses one, your LiPo charger and power supply use them, your TV and PC use them etc etc.

I've yet to experience one that fails by passing through full unregulated voltage. I'm not saying that it cant happen, or that it has never happened, but based on my experience if they are going to fail they usually do so by cutting all power. This stands to reason when you think about it because if a component fails then it usually goes 'open circuit' and stops conducting. For example, how many cases do you know of where a LiPo charger has passed full AC wall socket voltage into the battery?

But I agree, a simple battery is almost certainly the most reliable solution. Having said that the battery option did cost me some flying just this weekend because I forgot to put my 2s Rx batteries into my flight bag which kept a couple of my helis grounded I still flew my two helis that have BEC's installed

[IrvingWashington]

Well I have no evidence at all other than the reports from the people in the forums. I tried to do my research about becs before going 2s unregulated myself. I've found several reports that castle super bec and other becs aswell sometimes pass full voltage to the receiver, specially when going on 12S setup (I could'nt find any report of fail in a 6s setup). I've found also a lot of people who has used those becs without any issue for hundreds of flights.

I wont take the risk, thats all , and...yes, it sucks to have to carry the 2s battery packs XD.