BEC 101 Video

[Boomer2282]

hello bob i am a newbie and just want to know why would you need a bec if you have one already in the esc i have a trex 250 and a trex 500 and they came with the esc's with bec i may sound dumb but i would like to learn about it thank you..

[Finless]

Some ESCs that use 6S and up do not have a built in BEC. So your right, if your ESC comes with a BEC simply use that and you dont need a separate BEC.

Bob

[Jermo]

Nice Video Bob, well done
Jerry

[Josh May]

Thanks for the tip on using the gyro gain plug to get power from the BEC to the receiver.

I have a few 6 channel receivers that I will have to start using again.

[helicopter1]

Should i use the ferite ring on the external bec or the esc or both because i have some
glitching problems?

[madison0348]

that was what i call HELP i could not find anything obout ubec online so thanks alot Bob

[low.level.3d]

Hey bob,

thanks a lot for all your work here! Just great!!



I am thinking about my power supply in my new velocity90N
8917hv or bls351 on the swash
gy 701 gyro governor with bls251
throttle not yet decided



Would you rather use a BEC (which one and why) or a Regulator (e.g. Reactor X2) to power the electronics?

All my equipment is rated for 2S direct power.. (except taill servo bls251)


I dont care if the receiver, gyro unit and throttle run at 7.4 or at 5.2.V. I will just choose the throttle servo accoringly and maybe need a step down for the tailservo.
for sure I want direct 2S-power on the swash!

Just wondering whats the safest setup?


can you tell me something about the maximum current drawn by a 90 size nitro heli?

So is a 5A BEC/Regulator enough or do I need one that can handle 10,15 or even 20A?

cheers,

and thank you very much for your answer.

cyril


what about these things?

http://shop.rc-electronic.com/e-vend...=6&c=541&p=541

[Finless]

You dont say what RX your running? If Spektrum/JR then the RX can handle the 8V directly and so you can run all your servos except the tail direct from the lipo. You will need to step down the tail (and gyro) with a small 6V BEC. Do not use one of the step down Align gizmo's as they only drop .7V.
Another choice would be to get the AR7100 or 7100R (7100R has built in rev limiter which I like). The 7100 has a built in regulator for the tail and throttle servo and your cyclics can run at 8V.

Bob

[low.level.3d]

hi ,


thanks for the answer.

I will be running Futaba 8fg and 6108sb receiver. Just got an answer from futaba that all their receivers are rated fo 8A continuous and 10A burst overall!!

So, will this be enough for servos like 8917hv 8717hv? Not sure!!

If you are running direct 2S. How do you connect the battery to the rx? (1wire, 2 wires, how thick are the wires and do you use a switch, or no switch?? (which one?)

I am just thinking about the safest and most reliable rx power setup I can install!


thanks!

cyril

[panz]

Hi Bob,

Great video! I just ordered my 450 sport super combo kit with AR6110e (6-channel Rx). Does it mean I need to join the BEC's black wire that goes into the Rx together with the ESC's black wire? if so I how do I solder them together? any suggestion? Cheers

[Finless]

You are not using the Align ESC with the combo? You don't need a separate BEC if you use the Align ESC as it has one built in.

Bob

[panz]

Originally Posted by Finless

You are not using the Align ESC with the combo? You don't need a separate BEC if you use the Align ESC as it has one built in.

Bob

I am, but most would suggest to run a separate BEC (5v) to tackle the issue with DS410M servos. what are you thoughts on this?

[Finless]

Been running stock with stock ESC since day one. No issues here.

Bob

[mejmea]

It appears that most people who use a BEC solder it to the battery leads on the ESC. For a relatively small/small servo current heli like a 450 Pro, would there be any real downside to instead powering the BEC via the balance connector for the battery? (i.e. attach a connector to the BEC that is compatible with the balance connector for your pack, just using the two appropriate pins to get full pack voltage). I realize that the balance leads are much smaller wire gauge than the main leads, but I believe they are typically capable of at least 3 amps and it doesn't appear that you'd pull even that much unless you are really flying hard (not to mention that the stock BEC in the 35X ESC is only capable of 2A).

It seems to me that this would have the advantage of 1) being relatively easy to do, 2) You could move the BEC easily between aircraft (although they're relatively cheap so that may not be a real issue) and 3) most importantly, you could easily hook up the BEC to set up servos etc. without having the ESC powered and thus add one more layer of safety in avoiding unintentional spool-up.

Thoughts?

[Finless]

It should work OK. Some guys are doing it today on 12S systems. They are running the BEC off of one 6S pack balance port. The only comment some have about it, is it's another point of failure. e.g another connection that could fail and if it does, loss of control.

Bob

[mejmea]

Originally Posted by Finless

It should work OK. Some guys are doing it today on 12S systems. They are running the BEC off of one 6S pack balance port. The only comment some have about it, is it's another point of failure. e.g another connection that could fail and if it does, loss of control.

Bob

Good point, thank you Bob. I can see where connecting/disconnecting each flight does offer the possibility of a problem although one does the same thing each time you balance charge a battery. Do you happen to know if having that connection fail in flight is something people truly have had problems with or is it simply a "theoretical" possibility? If you solder the BEC leads to the connector on the ESC don't you also have the possibility of the wires getting flexed over time as you connect/disconnect the battery and thus have the possibility of a "connection" failure in flight also? (I suppose one could solder where the leads actually attach to the ESC to avoid this problem.)

I'm not trying to argue or anything, just trying to understand what people's actual experiences have been in order to understand the potential probabilities/risks.

[Finless]

No it's just a theoretical statement.

Bob

[heathy]

Guys, just trying to get a take on this situation myself, new to larger helis so go easy.

I'm getting a 6hv running on 2 x 6s packs. Also a skookum 720 with powerbus.

Some are using a 2s lipo and external bec to powerbus then 720.

I am trying to get away with the xtra weight of a 2s and was looking for a 12s bec.
Seems the answer was in the last few posts.

So to confirm, external bec with balance board plug soldered on, which then gets plugged into 1 of the 2 6s packs.

Thus eliminating the need for a 2s pack, right?

Cheers...

[Finless]

Yes... or you can get the Western Robotics BEC that can handle 12S. That is what most people with a 6HV are getting based on posts I see.

Bob

[heathy]

Perfect, thanks Bob