FMS ESC delay

[zusto]

I have FMS p39, think I have issue with esc.
When I move a throttle stick from 0, throttle starts rotating but delays to follow the stick, after 1-2 seconds prop starts rotating it is in full alignment with throttle stick. I have programmed ESC to Soft Acceleration Start ups with a linear throttle response, calibrated throttle stick but there is no change.

Any ides how to correct the delay

[OV10]

RE: FMS ESC delay

Hello zusto and welcome to this forum,
FMS ESC's usually have three acceleration settings.
A soft acceleration start setting provides initial slow 1 sec ramp-up from start to full rpm. This setting is recommended for fixed wing aircraft with gear drives or heli's.
Since you are flying the P-39, it requires the normal starting acceleration because of it's direct drive motor.
Reprogram the ESC to the "start" acceleration(forget about "very soft" and "soft" settings unless your flying a helo) and you should be good to go.
Best regards,

[zusto]

RE: FMS ESC delay

OV 10 thank you for your response, i did before and repeated today ESC setting as you mention in your comment, but it didn't help.

[Konrad]

RE: FMS ESC delay

I wonder if you are noticing the ESC's routine used to find the motor's rotor position. Sensor-less ESC have to find the rotor position before they can start the commutation process. This is done by sending an electrical pulse down the field windings and looking for the voltage feed back on the other two field winging (remember that cutting a magnetic field with a wire will induce a voltage in that wire). This tells the ESC where the rotor magnets are and which field winding to energize for the correct rotor rotation. This pulse often causes the rotor to rock or even rotate a bit before the ESC starts to run the motor in ernest.

I have to ask if once the engine is spinning does the motor respond to the throttle stick in a timely fashion (2 or 3 millisecond)? If your delay is just at start up this is normal. Motors with fewer winding (higher Kv ratings) in the coil can show a more marked delay.