BEC 101 Video

[dogfart]

Originally Posted by dogfart

Will the name of this thread still include the word "New" years from now?

I guess not. That's an improvement!

[CHOPPER PATROL]

After watching the video and reading this thread I think I understand the whole BEC thing. Is it possible that an ESC would run not as hot with an external BEC rather than using it's internal BEC (assuming it has one), and would this be an advantage also? TIA

[Hansolo]

Finally got to watch the vids, man... info overload. All good though. A big Thank You "finless" for a wealth of information.

[Jim Wilson]

Originally Posted by Finless

OK I got asked to do a overview of what BEC is vs a regulator and what a BEC is and how it gets hooked up.

So I whipped this up real quick.

BEC 101 - What's a BEC and how do you hook it up (47 Megs)

Enjoy
Bob

I have the Align RCE-B3X, Do I still need to take the red wire off the speed controller?

[srhadden]

BOB, another excellent video! I'm learning so much from your videos and helifreak in general. Absolutely SUPERB.

The reason I watched this, is I just bought a blade 400 as a "warm up" heli for my trex 450. First hover of the B400 in hot weather and the damn thing appears to overheat and drop power. So I heard there is a BEC "patch" out there for $25 to alleviate this issue. If I decide to do it, jeez, I know exactly what to do and why it works. Amazing.

They should call it a RTU (ready to upgrade), not RTF.

[oded mazor]

I understand the whole BEC thing, no problem.

just don't get why the TREX 600 package is delivered with a lipo 2S pack and regulators instead of a healthy external BEC to replace the whole electronic mess they supply...

[Andyk1]

Ok So what do you do with the TREX 600ESP which comes with both. A 100amp ESC which runs on 6s lipo's and a separate 7.4 volt BEC with a 5.1 volt stepdown?. Now I'm really confused.

[Pinecone]

You run the 6S pack to th ESC fo rmotor power, and the BEC (sic) off a 2S pack to power the electronics.

IMO, that is NOT a BEC, it is a VR. BEC means Battery Eliminator Circuit, so if you have to power it with a separate battery, it isn't eliminating a battery. That makes it a Voltage Regulator.

That regulator converts the 7.4 volt (nominal) 2S lipo voltage down to 5.8 volts for the Rx and servos. The step down geos to the tail where most tail servos are happier with more like 5.1 - 5.2 volts.

If you build the Fireup BEC you can hook that too your 6S flight pack and truely eliminate the extra battery. Or you can buy any number of comercial BECs that are rated to 6S or higher.

[kluson]

Hi Bob,

great video many thanks
I have a Spektrum 6100E which hs 6 channel inputs and a batt input. Will it be OK to put the BEC into the batt input on the receiver thus saving me from having to go into the 401 yellow wire plug?

kind regards and sorry if this is a dumb newbie question.
many thanks

[Finless]

Yes you are perfectly OK doing that. That is what the BATT connection is for!

Bob

[kluson]

thought it would be OK just wanted to be sure thanks a lot, sorry for the newbie questions

[Harold Roberts]

Originally Posted by Pinecone

You run the 6S pack to th ESC fo rmotor power, and the BEC (sic) off a 2S pack to power the electronics.

IMO, that is NOT a BEC, it is a VR. BEC means Battery Eliminator Circuit, so if you have to power it with a separate battery, it isn't eliminating a battery. That makes it a Voltage Regulator.

That regulator converts the 7.4 volt (nominal) 2S lipo voltage down to 5.8 volts for the Rx and servos. The step down geos to the tail where most tail servos are happier with more like 5.1 - 5.2 volts.

If you build the Fireup BEC you can hook that too your 6S flight pack and truely eliminate the extra battery. Or you can buy any number of comercial BECs that are rated to 6S or higher.

I am running my T600E with the 2s pack. However I've had recommendations to power the electronics off of the main 6s pack by using the balancing connectors to get 2s from the main pack. This would reduce the heli weight and prevent a source of failure that in my case has caused a crash. I don't like having to monitor two battery packs and strap 2 packs on for changing packs. The power draw of the electronics is so low, I don't think it would really impact the duration of the main pack.

Is this crazy?

Hal

[Finless]

I have heard of people doing that and have to say it's not the first time i have thought about it!

I say TRY it and see how bad the packs balance while charging! I have not tried it myself but thought about trying it many times. I cant believe one flight load of electronics would but 2 cells out of balance that bad!

Bob

[ENDO1]

Originally Posted by Pinecone

You run the 6S pack to th ESC fo rmotor power, and the BEC (sic) off a 2S pack to power the electronics.

IMO, that is NOT a BEC, it is a VR. BEC means Battery Eliminator Circuit, so if you have to power it with a separate battery, it isn't eliminating a battery. That makes it a Voltage Regulator.

That regulator converts the 7.4 volt (nominal) 2S lipo voltage down to 5.8 volts for the Rx and servos. The step down geos to the tail where most tail servos are happier with more like 5.1 - 5.2 volts.

If you build the Fireup BEC you can hook that too your 6S flight pack and truely eliminate the extra battery. Or you can buy any number of comercial BECs that are rated to 6S or higher.

Halle-freakin-lujah..

I'm putting together a 600ESP and scouring this board trying to make sure that I understood what a BEC is, and why my kit came with a "BEC" ( Align REC-B6X) and the schematic clearly shows another battery driving the thing...

Jeesh..

Thanks much PC!

[VORTEX25]

Originally Posted by fireup

He's just saying that some BEC has an input for your ESC and it disconnects the red wire for you and feed the control signal through... Personally I like to plug my ESC direct to the Rx so it's more reliable.

HEY Bob thanks for those videos you the man sweet.

[zbarry]

Bob,
I am running a 6 channel reciever. Can I plug my BEC into the BATT/BIND section?
Thanks

[Finless]

Yes... as I said in the video ALL connectors share a common positive and negative buss bar. so to power the RX and everything else ANY plug on the RX can do that.

Bob

[NorwegianEagle]

I have understood that if I'm running digital servos I should have an extra BEC, but why do I need an extra BEC when my ESC already has one? Is the BEC in the ESC also hooked up to my motor, or is it just to weak to tolerate modern digital servos pulling a couple of amps?

Im going to get one when I'm buying a new heli that is around logo 400/ t-rex 500 size, I just don't understand why the BEC in the ESC cant do it.

Thanks.
Max

[Finless]

It has nothing to do with running digital servos. It has to do with AMP draw from your servos and what the AMP output capability of the BEC is that is built in the ESC. Some ESCs have a BEC with only 2-3 amps max. If you put in servos that can draw more than this then that is when you need a external BEC with a higher AMP capacity.

You dont say what ESC and servos your using and in what heli so it is impossible for me to say in the built in BEC in your ESC will handle what you need.

Bob

[frogs84ss]

wow im just a noob with lots of rc car history and thought what can there be to know about a bec! i'm shocked and awed. great video you covered everthing and answered every queston i had while i was whatching as if you could hear what i was saying . thanks for the lesson it has been learned and will be used