hsanchez

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Good Evening. I am assembling a Maxford Neptune Boat Plane for an upcoming Float Fly. This is the first time I have tried using an electric motor in this plane. The assembly instructions suggest that I should always use a cable extension between the motor and the ESC, if an extension is necessary, but to NEVER use a cable extension between the ESC and the battery. I may need to place the battery in the forward portion of the fuselage, which would require a 3-wire cable extension up through the carbon fiber tube to the elevated power pod where the motor would be. The ESC would most likely have to be in the fuselage as well. The cable wires would have to be 10 gauge. I don't know of any outfit that sells these cable extensions. Does anyone out there know where I could buy some? Please advise.

Thanks,
Harry Sanchez
[email protected]

rgburrill

Home Depot or Lowes. Power cable extensions don't look great, but you can hopefully hide them. I also suggest using 5mm bullet pairs for the connections. You will lose a slight amount of voltage but it's unlikely you will notice it.
BTW, you can use either a 3-wire cable or 3 separate wires. 3 separate wires take less space but can be a pain to work with.

RCoffroadracer

the reason they don't suggest an extension on the battery i'm thinking, is because you can fry a lipo battery with one short of the + and -. they would surely get 50% of ding dong customers wanting a new battery from them because they said to extend the leads and it caused them to hook it up backward or they let the wires touch. and getting 10awg wires to match the battery is harder to find than a 12awg and 16awg wire for the motors.

I would only suggest wires made for our hobby. not something from home depot. even the silicone wires on Amazon are better suited. the problem with amazon is you have to buy it in bulk usually.
my preferred wire would be ws deans ultra wire. https://www.wsdeans.com/collections/ultra-wire

ron_van_sommeren

It's because long battery wires create voltage spikes that are higher than battery voltage.
At same frequency as user selected Pulse Width Modulation frequency, 8, 16 or 32kHz.

Too long wires batteryside can kill ESC over time: causes, precautions, solutions & workarounds - RCG
Length of battery wire between packs counts too.

Keeping/tying/taping the plus and minus battery wires close together also helps reduce wire inductance (table).
You could take this a bit further by removing the insulation of one the two wires, reducing the distance between the copper cores even further.

Contents

• Two problems
  • Voltage spikes higher than battery voltage: transistor / powerFET / die breakdown.
  • Current through input capacitors too high: caps overheating/popping/exploding.
  • Nonsense Ron, I never had problems with long battery wires.
• Example: four costly controllers consecutively cremated
  
• Solution I: simply lengthen the motor wires instead
• Solution II: add extra capacitors, rules of thumb
  Calculation spreadsheet
• Capacitor type and polarity/orientation!
• How & where (not) to add extra capacitors
  All capacitors as close to or on controller, do not distribute along batterywires.
• DIY capacitor pack pictures
• Capacitor & pack suppliers
• Expert/manufacturer opinions & their rules of thumb
  They all say the same ... noise_reduction_101, switching_power_supply_design_101.
• Cause, explanation, water hammer/knock analogy&
  video
  , theory
  References
• Measurements & scope traces

Vriendelijke groeteen Ron
• Without a watt-meter you're in the dark ... until something starts to glow •
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