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Question about BEC setup on a Acro Naze32 board.

#1
I purchased a Suppo 3A External BEC since my ZTW Spider 20A OPTO ESC's don’t provide power. Since this is my first Quadcopter build, I want to make sure I understand how to connect the BEC correctly.

Could I take M1 ESC and pull the signal wire out and plug that single wire into the BEC and then plug the BEC into my Naze 32 board for M1? Then plug the rest rest of the 3 remaining ESC's to the following M2, M3 and M4 pins? See Picture diagram for an example. Any advice would be appreciated.

ESC to BEC setup.PNG

Thanks,
 

Craftydan

Hostage Taker of Quads
Staff member
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#2
yup.

If your ESCs and BEC all share the same power source (battery), they should all have the same ground and that should work just fine.
 
#4
Quick question(s): I am building a HMB235 with opto ESCs (DYS 20a). I notice they come with a signal and ground wire, but i've seen alot of setups with only a signal wire coming from the esc to the flight controller.
1. Are the ground wires really needed? You implied no earlier, but i'm confused as to why they would then all come with ground wires. It sounds like i can just unsolder the black wires twisted around the signal wires.
2. Can i solder wires directly to the pins on the naze32, or do i have to hook them up to a servo plug?

Specifically, these are are my ESCs:
DYS-ESC-SN20A.jpg

As always, thanks for any feedback!
 

Craftydan

Hostage Taker of Quads
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#5
1. Are the ground wires really needed? You implied no earlier, but i'm confused as to why they would then all come with ground wires. It sounds like i can just unsolder the black wires twisted around the signal wires.
Maaaaaybe.

The Opto ESCs can be a slightly odd creature, and it depends on what the manufacturer means by "opto".

The formal definition is "optically isolated" -- this is an term that crosses industries and means there is a electricity-to-light-to-electricity gap between the high voltage inner workings and the low voltage external control signals. it's used on bigger airframes to isolate noise, but the key to it is that in the process the grounds are isolated as well.

The marketing definition that some cheapo manufacturers have adopted is "Lacking a UBEC". It's done to save weight and cost, although the regulators built into most UBECs are a under $0.25/ea in quantity and weigh next to nothing -- under 10A it makes a big difference, but bigger ESCs this type of "opto" isn't much better.

There are far more of the latter on the market to lean that way by default, but the others are around. In either case, it's easy to check which one you have with a multimeter -- if you've got continuity between the battery ground and the signal ground, it's not isolated, and one wire will do. If you don't, it is isolated and you MUST connect both wires.

2. Can i solder wires directly to the pins on the naze32, or do i have to hook them up to a servo plug?
Must? No. Good idea? That's up to you. My personal experience is that the moment I hard solder something in, I need to reroute the cable, or replace a part, or retest a component, or . . . you get the idea. I won't say I've regretted that *EVERY* time, but I've regretted it enough that I've stopped doing it . . . well, stopped until I think myself clever enough it no longer applies and remind myself why I don't do it that way . . . again.
 
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#6
Thanks Dan - that was interesting information! I think i can summarize that by saying, "best to leave the grounds connected!".
 

sphinix

intermediate quad pilot
#7
Its easier, and safer to just backload it through the receiver. Most recivers have a spare plug for binding or for a battery. Which it specifically for this method. If it doesnt just put it in an unused set of positive and negitive ports or an unused channel. Then it should power the naze32 through the positive and negitive wires that run from the reciver to the naze. I do this on all my models. And i have several.
 
#8
Its easier, and safer to just backload it through the receiver. Most recivers have a spare plug for binding or for a battery. Which it specifically for this method. If it doesnt just put it in an unused set of positive and negitive ports or an unused channel. Then it should power the naze32 through the positive and negitive wires that run from the reciver to the naze. I do this on all my models. And i have several.
You do this with opto esc's? You still have to down-regulate voltage to 5v going into receiver though correct?

My original plan was to out a down regulator between Power Distribution Board and Naze32 and let receiver be powered form naze.
 

sphinix

intermediate quad pilot
#9
Oh of course. The reciver takes 5 volts just like the flight control. And most regulators come with a sevo plug set up and everything. If your using a pretty typical bec. The you even save a bit of soldering with this method. All positive and negitive pins are normaly on the same rail. So it spreads the power out evenly. Though if you plan to use some very strong servos you may want to consider your amp draw ill post a picture of my setups when i get home tonight. But i get off really late.
 
#10
I like the idea of doing it your way. I fried my voltage regulator because i got my voltage in and out backwards - your way seems like it would be easier to avoid that in the future.
This is what i was going for originally, but got my wires mixed when i unplugged them & replugged them.
Naz32 wired up with Pololu_zps3mdctqi9.jpg
I ordered a new pololu, but also a combined BEC/PDB
 

sphinix

intermediate quad pilot
#11
I mabey wouldnt put it in vbat. I dont know mutch about that port, but i dont think thats what its for. Unless you know what your doing
 
#12
hmb235 is my first quad build, and i'm doing it per their specs on the multiRC site. My understanding is that a voltage regulator is essentially just a BEC.
 

sphinix

intermediate quad pilot
#13
Yes. A bec is just a very common type of voltage regulator. It has property's that just makes it very useful and easy for rc
 

Craftydan

Hostage Taker of Quads
Staff member
Moderator
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#14
The VBat port is for a battery tap to the FCB to read the unregulated voltage from the battery. This allows it to alert on low voltage either on the buzzer or through telemetry (OSD or Radio).

As long as Vin and GND on the regulator are also connected directly to the battery, that wiring should work . . . just don't get 'em backwards again ;)
 

sphinix

intermediate quad pilot
#16
They can be great if the regulators actual work. I have that same board, but i never hat the chance to test it. But most cheap ones ive owned never seem to work. When i bought my reptile Mosquito, it came with a customized board rated to 6s. And 4s cooked the biultin bec. I replaced it with a hobbywing bec and it works now. My advices. If you biuld alot and your impatient like me. Buy a couple of cheap becs and keep them around to solve problems like that
 
#17
well, i got paranoid and set everything up with an UBEC (and didn't use the pololu voltage regulator or the combined PDB/BEC). Everything is working, and hopefully in the next few days i'll get to see if i did the cleanflight setup correctly.
 

sphinix

intermediate quad pilot
#18
Never hurts to test it. BECS. arnt like flood gates. If it fails it doesnt open the fury of your battery on the electronics. But more like a bridge if it fails it just stops giving power to your FC.

Im ment mine failed like burning out and never powering anything. 4s my have just been to much for mine