BEC 101 Video

[lightbulbjim]

My understanding was that the ESC needs to power its circuitry at ~5V (or at least something other than the flight pack voltage, which can vary a lot depending on how many cells you're running etc). If it's got an onboard BEC then it's got a 5V supply, otherwise it needs power from somewhere.

On my Hurricane 550 I'm using the Align 75A ESC and a SportBEC. I followed the directions on Dimension's site for connecting up an ESC with no internal BEC as it makes sense to me: http://www.dimensionengineering.com/...stallation.pdf

Hehe, I just noticed that this is also being discussed in Fireup's DIY BEC thread



PS: I'm NOT meaning to sound patronising here, apologies if that is so. I'm a bit of an electronics noob.

[Billybuck]

Thanks for the video Bob. Very informative.

[Sugarbaker]

so are there benefits for a set up that uses a separate RX battery (along with a regulator)? Or is it always better to use the main battery and a BEC?

[Finless]

Originally Posted by lightbulbjim

My understanding was that the ESC needs to power its circuitry at ~5V (or at least something other than the flight pack voltage, which can vary a lot depending on how many cells you're running etc). If it's got an onboard BEC then it's got a 5V supply, otherwise it needs power from somewhere.

On my Hurricane 550 I'm using the Align 75A ESC and a SportBEC. I followed the directions on Dimension's site for connecting up an ESC with no internal BEC as it makes sense to me: http://www.dimensionengineering.com/...stallation.pdf

Hehe, I just noticed that this is also being discussed in Fireup's DIY BEC thread



PS: I'm NOT meaning to sound patronising here, apologies if that is so. I'm a bit of an electronics noob.

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

[wrathofkhan]

hello

i had a jazz 80-6-18 on my swift, and i had was using a 4.8volt battery pack (the receiver was getting power from both). it flew fine without any problems, actually the instruction sheet which came with the Jazz actually suggested it.

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 ?

look forward to your feedback ... khan

[lightbulbjim]

Originally Posted by Finless

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]

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

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]

Originally Posted by Finless

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?)

[HeathH]

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]

Originally Posted by dogfart

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.