Advanced Setup

Further details of the F-Series ESC setup including recommended prop/motor combination, tuning, firmware updates, and audible tones.



Regular checks and maintenance should be performed on the ESCs, especially after crashes. This includes:

  • Inspect for any broken or chipped components on both the top and bottom sides.

  • Power on using a smoke stopper or low-voltage battery to ensure electronics are not damaged or getting hot quickly.

  • The no-load current draw of the 120A ESC is 40mA. This can easily be checked by de-soldering the ESC from any PDB or wiring harness, and powering on using a 3S Li-Po. If the ESC draws less than 35mA or more than 45mA, there is a damaged component on the board.

  • Capacitors that are swelling or bulging should be replaced immediately. Excessive heat and high-current loads will reduce the capacitor's life. The performance drops over time, so the capacitors should be replaced every 20-30 flights, even if no visible degradation exists.

Protection Mechanisms

The F-Series ESCs contain the following factory configured protection mechanisms to ensure maximum product lifetime:

Phase Current Limiting

The motor phase current is limited to the maximum burst rating for each F-Series ESC. These are as follows:

  • 40F3 ESC: 100A Limit

  • 100F3 ESC: 180A Limit

  • 120F3 ESC: 200A Limit

  • 200F3 ESC: 300A Limit

Over Temperature Protection

All ESCs are set to 110°C, at which point the maximum throttle is limited to a 50% duty cycle.

Over Voltage Protection

All ESCs will reduce regenerative braking response when a voltage rise is detected on the bus while braking.

Motor and Prop Size

Correct motor and propeller selection is very important to reduce the load on the ESC and to reduce motor saturation. Incompatible combinations can result in reduced overall performance, reduced system lifetimes due to excess heat and even ESCs burning out. If the prop and motor combination draw more than the ESC's nominal current rating at a static load, they are not recommended. For reference, a system running a 120F3 and a MAS 13x12x3 propeller should have the following motor Kv:

Cell Count

Recommended Kv









In order to use larger propellers, either the motor Kv or battery cell count should be reduced.


For tuning the flight controller with BetaFlight, we recommend the MPU6000 series accelerometers. ICM gyros are low-power and more susceptible to noise.

PID Tips

If increasing frame size by X%, then increase your P-value by X%.

If increasing prop size or rpm by X%, then reduce your P-value by X%. Start with a lower I and D value, and gradually increase them.


On larger frames filters play a large role in the effectiveness of PID set-points. The lower the filter values, the better the system performs.

The ESCs update loop-time is much higher than the frequency of the vibrations that pass through the arms of larger machines. As a result, the vibrations will be equally seen at the flight controller as they are at the motors, resulting in the need to filter them out.

Firmware Updates

Note: All APD ESCs supplied in black satchel bag type packaging contain combined DShot + PWM firmware, and will no longer require flashing to switch.

The ESCs are updated through a USB to UART bridge using APD supplied firmware from our Shop Page. Each ESC has the firmware versions available for download under the Firmware tab (downloads require an account to be created through the site). A USB to UART adapter can be purchased from APD.

All FTDI and SiLabs bridges are supported and known to work. The 200F3 ESCs have a Micro USB port, so a UART bridge is not necessary. The UART PADS are located at the bottom edge of the PCB, along with the boot loader short points. Due to a 1K Pull-down resistor on the signal input (for noise suppression), a pass-through system cannot be used.

To flash new firmware onto your ESC, ST's flasher tool is used. The steps to flash new firmware onto the ESC are as follows:

  • First, connect the boot loader pins together, which are either next to the UART pins or the USB port (ESC model dependent).

The F Series ESCs have different UART pin-outs, see below images for reference.

Pin-out for 40F3 ESC
Pin-out for 80F3[X] ESC
Pin-out for 100F3[X] ESC
Pin-out for 120F3[X] ESC
Pin-out for 200F3[X] ESC
  • Once the pins are connected, connect the ESC to your computer.

  • Startup ST Flasher, and make sure the correct COM port is connected. If your COM port does not appear here, make sure all the device drivers are installed.

First Menu on ST Flasher
  • Click Next and wait for a connection to be established. If the program times out, check the boot loader pins are connected, re-plug the ESC to the PC and try again.

Second Menu on ST Flasher
  • The Target readable screen occurs when the connection was successful, click Next.

  • Click Next on the following screen too, no further changes need to be made.

Third Menu on ST Flasher
  • Once the following screen is reached, make sure you click the Download to Device option, and select the firmware file that was previously downloaded. Don't change any other options here.

Do not click global erase as this will completely erase your ESC and require APD re-flashing.

  • Click Next, and once the Flash has been completed, the ESC can be disconnected. The connected boot loader pins can now be disconnected.


Once the ESC is connected to a motor and powered on, the following sequences of tones give statuses and errors as they occur. The tones occur in either high or low beeps (high and low frequency).

Power Up Tones

Tone Sequence


3 High, 1 High, 1 Low

PWM or ProShot detected + Armed

2 Low, 1 High

DShot detected + Armed

6 Fast High Tones (5-second repeat)

An Incorrect signal detected on power-up, throttle too high for arming

1 Low Tone (2-second repeat) or white LED

Waiting for valid signal input

After Arming Tones

Tone Sequence


1 High (5-second repeat)

Normal operation, waiting for throttle

3 Low (5-second repeat)

Thermal limit exceeded last flight

As always, reach out if there's any issues or questions, we try to respond as soon as we can. Contact options can be found under Help.