Speedracerntrixie, do you work for Dualsky??
I have been running electric F3A models since 2010, have had no issues with previous setups and NO motor failures until I tried Dualsky.
I currently run a Plettenberg with the same size prop on another model without any sign of failure and have been for 4years.
Previous to this I was running a Hacker Q80 from 2010-2017 no issues either.
I run a delay on the throttle channel so large current spikes or draw are not experienced.
Below is a direct extract from an email by Dualsky.
You mentioned that you used PT 20x13, but if it's 3-blade propeller. The load was too much for XM6250DA-220KV. This maybe the reason.
The right setup is : 20x13EL(3-blade), XM6355DA-13 200KV.
Good day.Hobbyservices 2
I have admitted that the XM6250DA-220KV was my fault if you read the previous emails.
I then purchased "
The right setup is : 20x13EL(3-blade), XM6355DA-13 200KV" from Dualsky which lasted for 16 flights before the magnets have moved.
If you can't trust the manufacturer who can you trust? This was their advice.
The failure
After landing the motor is 52Deg C, however when the magnets came loose the motor registered 91Deg C probably due to the extra friction caused by the magnets dragging on the internals.
Motor previous to failure never got hot, also my batteries didn't even get warm enough to measure on the indicator strips.
Burst current for motor is 93A for 15secs
Peak power 3430W for 15secs equates to 81.7A
Cruising power 1890W for 30mins equates to 45A
Firstly when I fly I hardly get to full throttle, if I do it's only for about 1-2secs max.
Most of the schedule is at 1/2 throttle or idle with the exception of some verticals which is covered above. Most verticals done at 3/4 throttle.
My cruising power is slightly higher than the quoted figure about 50A however the flight is over within 8mins so everything as a whole is within tolerance.
As for air flow, setup has
- Falcon carbon fibre cooling spinner
- Custom mount cutouts to suit Dualsky mounting
- Vents next to motor opening behind mount mount
- Vent cut into chin cowl with air deflector
- Large exhaust holes to let the warm air out
I don't profess to be an expert in electrics and mistakes are made as I said earlier. When this happens I take full responsibility.
The fact is the motor failed when it shouldn't have.
Dualsky now claim the setup is incorrect after putting it in writing "
The right setup is : 20x13EL(3-blade), XM6355DA-13 200KV", who's mistake is it?
Even though they have said they will replace the rotor on this occasion, I doubt I will ever see it.
Going to modify this model to fit a proper F3A motor in it, OS Belt Drive Unit
