BEC 101 Video

[lightbulbjim]

Well yes an no..... Some Opto Isolated ESCs do need power. But this is not the norm. The Align 75 ESC is not opto isolated and thus does not need power from the RX. Test yourself (Kevin just did it) and pull the red wire from the ESC. The ESC will still work. It has it's own little regulator on the PCB for the processor using the main battery for power.

Bob
Ah ok. Since the Align 75A ESC is designed to be used with either a seperate BEC or a receiver pack I take it that the red wire goes nowhere anyway? As in there's no advantage or disadvantage in leaving it as is?

If the red wire was connected to something in the ESC then I guess it could be another source of switching noise in the receiver, but with a BEC-less ESC I would think the red wire would just be dead anyway.

I'm just curious about these things is all :o

[Pinecone]

OK, one person here had a problem with their Gaui 50A by hooking up a SportBEC in line as the ESC didn't do anything. Hooking them both up to the Rx allowed the ESC to get power from the BEC and it worked.

I ahve an Optoisolated ESC that needs BEC power to operate also.

I will test a few this weekend. But unless the ESC has some form of BEC in it, it needs electronics power from somewhere. I doubt that they run the electronics at 25 - 50 volts. :)

[Finless]

Interesting... My Gaui ESC the red wire goes no where! Under the clear heat shrink it is not soldered to anything. I know they had a few changes with those so they must have made it OPTO or something to stop the issues people were having.

Anyway it is clear some ESC's need power from the RX but most of the BEC-less ESC's I have used did not.

Ah ok. Since the Align 75A ESC is designed to be used with either a seperate BEC or a receiver pack I take it that the red wire goes nowhere anyway? As in there's no advantage or disadvantage in leaving it as is?

Yep the red wire goes no where! Leave it as it is.....

my question is isn't this similar to having ESC with BEC, and separate BEC powering the same RX? from what i understood from this post, this was discouraged. i am wondering why ?

If the voltage is the same from the separate BEC and the ESCs BEC then fine you should be OK. BUT if they are not the same you dont want to do that!
Also one of the reasons some people went to a stand alone BEC was to help fix RF noise on FM radios. This was befor Spektrum of course. So they didnt want noisy power coming into the RX.

Bob

[diveman123]

I have to watch this stuff many times before I can attempt it. Thanks for the time you put in man.

[dogfart]

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) (http://video.helifreak.com/?subpath=finless/generic&filename=bec101.wmv)

Enjoy
Bob

Help! I can't run the vid. Is anyone else having a prob. with it? (I really want to see it too, because I just had an Align 100A ESC burn up on me!)

[dogfart]

Huh? The ESC doesnt need power other than from the main pack BEC or no BEC. The only thing the ESC needs from the RX is a throttle signal.

A real BEC (not a regulator) gets it's power from the main battery and converts it to 6V or 5V to power the RX.

Bob


Please tell me if the following is correct:
75A ALIGN ESC
This unit has a built-in BEC, so there is no need to attach a separate battery, or an external BEC, to power the reciever. This unit will power the receiver, just by plugging it into the "Throttle" output. Right?

100A ALIGN ESC
This unit does NOT have a built-in BEC, so you must power the receiver with a separate battery, or an external BEC. Right?

If you use an external BEC, you must sever the red (+) and black (-) "power wires," leaving only the white "signal wire" intact on the wire harness that plugs into the Throttle output in the receiver. Right? (Do I have the wire colors correct?)

(Do you need to sever the 2 Power Wires even if you use a separate battery to power the receiver?)

[hamslice]

the align 75amp does not have a bec built in.
when using an external bec you must remove the red wire from the esc. keep the black(ground) and the white(signal) wires. you need to keep the ground so the esc and receiver share a common ground.

[Finless]

Niether of those ESC have a BEC at all... THis is why in the 600 kits they also supply a regulator.

Bob

[dogfart]

Sorry, I meant the 35A versus the 75 & 100A. My questions should have been:

Please tell me if the following is correct:
35A ALIGN ESC
This unit has a built-in BEC, so there is no need to attach a separate battery, or an external BEC, to power the reciever. This unit will power the receiver, just by plugging it into the "Throttle" output. Right?

75A, and 100A ALIGN ESC
These units do NOT have a built-in BEC, so you must power the receiver with a separate battery, or an external BEC. Right?

If you use an external BEC, you must sever the red (+) and black (-) "power wires," leaving only the white "signal wire" intact on the wire harness that plugs into the Throttle output in the receiver. Right? (Do I have the wire colors correct?)

(Do you need to sever the 2 Power Wires even if you use a separate battery to power the receiver?)

[Finless]

Yes... now you are correct.

Bob

[dogfart]

Thank you. By the way, I just got your BEC vid to work!

[dogfart]

Also, since the Align 75 & 100A ESCs have no BECs, then why do they have the pos. feed wire to the receiver?

[Finless]

Because they get the connectors with wires on them and it's too expensive to remove the red wire so they just leave it unconnected inside the ESC.

Bob

[dogfart]

Holy Moly. In that case, why is it nec. to sever the wire?

[fireup]

Holy Moly. In that case, why is it nec. to sever the wire?

On ESC that don't have BEC, you don't have to cut the red/middle wire. On ESC that do have an onboard BEC you should cut the wire or else that voltage will conflict with your external BEC specially if you want to run 6V on your external BEC and your onboard is putting out 5V.

[dogfart]

On ESC that don't have BEC, you don't have to cut the red/middle wire. On ESC that do have an onboard BEC you should cut the wire or else that voltage will conflict with your external BEC specially if you want to run 6V on your external BEC and your onboard is putting out 5V.

Okay, that makes sense. Do you know how many Volts the BEC contained within the Align 35A ESC (for the Trex 450) puts out?

[Finless]

Align has 2 versions of the 35. The 35G which puts out 5V. It has a GOLD colored heat sink. The Align 35X which puts out 6V and has a blue heat sink.

Dogfart dude... this is documented on the Align web site and the instructions you get with the ESC! Not to harass you man but have you READ the freakin instructions that came with yours?

Bob

[HeliBurns]

Wow, this BEC thread is gaining momentum....:)

[Finless]

Wow, this BEC thread is gaining momentum....:)

Yea I am kind of surprised too... I had no idea that this BEC / ESC stuff was that confusing to people???? I shot this video kind of ADHOC on a request and I may have to do it again to cover all the questions!

Interesting for sure....

Bob

[HeliBurns]

Bob, I think it is a good thing....I think it's a subject that has been overlooked
for a long time.....

Our servo manufacturers are very vague on what max(or even average) current might be needed...and perhaps rightly so, as they can't predict what load is appropriate for everyone.....

I just wish they could spec at least the stall current so that we can "guesstimate" what we need from a BEC depending on what servos we are using...I tend to want to overspec by at least 50% just for piece of mind, even though it might not be necessary...but that's just me...:)

What is surprising to me is that linear regulators are even used at all, given the state of the tech. art of today's switchers....but again, who am I to judge...:)

I'm a happy camper.....just received my TR500...:)
Can't believe what a small box it is.......

[HeliBurns]

Bob, I also forgot to add this....

Perhaps a video could be made....that discussed ESD precautions that we must be careful of when handing sensitive circuitry.....I don't mean to burden you with
extra work, but you be the man...and people will listen to you......:)

[Finless]

Well me being a field rep for years and understanding ESD I would agree BUT I think you might be a bit over zealous on this one. You cant expect most guys to go out and buy a freaking ESD wrist strap and pad to work on their helis!
Honestly I have worked with CMOS for a lot of years and handled 100,000 circuit boards in my 30 years or so... In fact I have probably modified 10,000 astro CCD cameras and never had a failure due to ESD.
Look at this web page and what i was doing for a long time before I gt back into RC helis:
http://home.socal.rr.com/hotweb/vesta/vesta.html
The home page is here too if you want to look
http://home.socal.rr.com

Anyway I am NOT disagreeing that ESD is a problem I am just saying that I think some people are way to paranoid about it!

I don;t see an ESD video in my list of videos to do anytime soon... If you think it is that important go for it... These are consumer devices and as a consumer I SHOULDN'T need a class on ESD to use them... Sorry dude...

Bob

[dogfart]

Align has 2 versions of the 35. The 35G which puts out 5V. It has a GOLD colored heat sink. The Align 35X which puts out 6V and has a blue heat sink.

Dogfart dude... this is documented on the Align web site and the instructions you get with the ESC! Not to harass you man but have you READ the freakin instructions that came with yours?

Bob


Call me a 'tard. I am pretty sure that I had read the instructions, but I did not see the answer there. It did not occur to me to try the website though.

EDIT: By the way, thanks for the answer though.

[HeliBurns]

Bob, while you're experience in the handling of CCD devices over your distiguished career is outstanding.......having said that, I am totally amazed
that you make such statements that discount any ESD effects....

If your point of view is such that it's too much of a hassle for the average person
to take care with respect to ESD..then you are inadvertently doing people a diservice...one can simply ground themselves with a PC power cord......

Bob, you go ahead and handle circuitry in the manner that you are familiar with....
but please don't discount how your mishandling of such circuitry is of no consequence to the end user...

'Nuff said

[da.tsun]

Can anybody tell me how to download videos I click and all I can see message from members

Thanks