Large frame ESC placement

[Flydigital]

I have a 110cm octo frame which I am about to rig with motors and ESCs. I was planning to put the escs right on the very end of the frame as per the picture here.

I read elsewhere that having long wires to the ESCs is not good. Distance from ESC to power and controller etc. would be 50cm. It will be PPM controlled if that makes any difference.This looks like the best place to put them as it leaves more space in the centre for other stuff. Thanks for any advice on this.<script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/c04dba10/background/helpers/prefilterHelper.js"></script>

 

[Hexacrafter]

This has been a HOT topic on the forum many times. If you do some research, I think you will find that extending the +/- input power to the ESC will VOID the warranty and any manufacturer support of that product. All of the Electronics Manufacturers we have close relationships with would not support the proposed configuration, but rather using long wires from the ESC to the motor. None of those we work with even will support or recommend ANY lengthening of the ESC +/- inputs beyong that provided on the ESC.
I suggest you ask this question directly to the ESC manufacturer that you are planning.
There are most likely "Many" that will disagree with my responses, but our directions to our clients come directly from the manufacturers we recommend.

 

[Flydigital]

I'm using Turnigy multistar ESCs. I can't see anything saying you can't extend in the PDF but will go with what you advise! Thanks for the help.<script type="text/javascript" src="safari-extension://com.ebay.safari.myebaymanager-QYHMMGCMJR/c04dba10/background/helpers/prefilterHelper.js"></script>

 

[mathias_popsel]

Hi, i am building an octo with the same ESCs, i placed them also under the props. yesterday i put power on the ESCs and unfortunately i fried 1 ESC immediately ... the other 7 are OK. i think it has nothing to do with the lenght of the wires, probably a production fault...

 

[gtranquilla]

Hi, i am building an octo with the same ESCs, i placed them also under the props. yesterday i put power on the ESCs and unfortunately i fried 1 ESC immediately ... the other 7 are OK. i think it has nothing to do with the lenght of the wires, probably a production fault...

Yes a production fault IMHO.
I had one of my Turnigy 45 amp OPT ESCs fry the first time I powered it up for the intial bench test...... (that was one in approximately 20 that I have used over the past couple of years).
I always test new electronic components as soon as they arrive......... adivsed HobbyKing and they agreed to replace it at no charge.....

As far as ESCs placed out under the motors....... DJI has been doing that for a long time......there are no impedance issues on the DC side..... but there may still be a slight increased risk of FET switching noise reflecting back into the PDB such that one problem motor/esc could affect others.

 

[jdennings]

Many people do it, it can be done right if not blindly. Besides possible void warranties, it requires replacing/beefing up escs capacitors. Googling something like "esc long power wire capacitor " will return plenty of hits.
You can also look up user redemptioner for a large octo build doing this on, hmm, another forum.

 

[FerdinandK]

Copter big enough?

All of my copter are build with ESC on the booms some of them are really big. Never had a problem (that does not imply that anybody else will be safe).
Big copter are big because of the propellers used, if the layout is somehow correct the bigger the copter the more efficient it will work, so e.g a 25kg 28" X8 has an average amps draw of 12,5A per motor on 8S, (so not really much). Also if there are two motors on a boom it is a good idea to "bridge" the capacitors (connect the two ESCs directly, as they will share ), and not to use two seperate power lines to the center. Also on the centers no fancy power-distribution, just make it as simple as possible, and as short as possible, with as few as possible connectors and solder in between battery and ESC (there should be at most one connector between battery and ESC). When you solder, try to mechanically connect copper and fix this with solder, not bridge a distance between copper-parts with solder.

best regards
Ferdinand

 

[gtranquilla]

Yes.... seen much of your coax work before from Austria including GPS waypoint missions etc.
Are you aiming for super long flight time or designing for heavy payloads?

Copter big enough?

All of my copter are build with ESC on the booms some of them are really big. Never had a problem (that does not imply that anybody else will be safe).
Big copter are big because of the propellers used, if the layout is somehow correct the bigger the copter the more efficient it will work, so e.g a 25kg 28" X8 has an average amps draw of 12,5A per motor on 8S, (so not really much). Also if there are two motors on a boom it is a good idea to "bridge" the capacitors (connect the two ESCs directly, as they will share ), and not to use two seperate power lines to the center. Also on the centers no fancy power-distribution, just make it as simple as possible, and as short as possible, with as few as possible connectors and solder in between battery and ESC (there should be at most one connector between battery and ESC). When you solder, try to mechanically connect copper and fix this with solder, not bridge a distance between copper-parts with solder.

best regards
Ferdinand

 

[FerdinandK]

I am just experimenting, sometime flighttime, sometimes payload and sometimes both is the result. But typically the aim is to carry some payload for some distance and some time. The more one of the numbers grow the more difficult it becomes. So to drop an number, 30min with 8kg payload and 40-50km/h speed is already on the market (and results in a 25kg AUW copter).

best regards
Ferdinand