Understanding ESCs for FPV Drones: How to Choose the Best Electronic Speed Controller

by Oscar
Flycolor Trinx G5 60a 4in1 Esc Silicone Coating Water Proof

In this article, we’ll explore the fundamentals of Electronic Speed Controllers (ESCs) and their role in FPV drones. This comprehensive guide aims to provide valuable information on voltage ratings, current ratings, different ESC types, and the anatomy of an ESC. Let’s get started!

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What is an ESC?

An ESC, or Electronic Speed Controller, is responsible for controlling the speed of motors in an FPV drone. The ESC receives throttle signals from the flight controller and drives the brushless motor at the desired speed. Using high-quality ESCs leads to a reliable and smooth flight experience, although many other factors also play a role in the overall performance.

ESCs are crucial to drone performance as they control the variable speed of motors. They are powered by direct current (DC) from your LiPo battery and take motor signals from the flight controller, providing three-phase alternating current to power the motor.

ESC Recommendations

How To Build Fpv Drone 2023 Fc Stack Nuts 2

I highly recommend opting for a complete FC/ESC stack because it can simplify the building process thanks to its plug-and-play nature. This approach minimizes the need to worry about wiring compatibility between different manufacturers. Check out my recommended flight controller stacks here: https://oscarliang.com/flight-controller/.

If you prefer purchasing your ESCs separately, I offer the following recommendations. When using a 4-in-1 ESC and flight controller from different brands, it’s crucial to verify the pinout before connecting them to prevent potential damage to the components. Always inspect and adjust the wires in the harness as needed before connecting.

Holybro Tekko32 F4 65A

Top of the Line

Holybro Tekko32 F4 Metal 65a 4in1 Esc Close Up Bottom

You can get the Tekko32 F4 ESC from these vendors:

The Holybro Tekko32 F4 65A is possibly the most robust and lowest noise ESC available, thanks to its impressive onboard noise filtering. You’ll be amazed by the clean power this ESC delivers. Utilizing one of the most powerful F4 processors in ESC, the Tekko32 is rated for 65A with an 85A burst current. It’s an absolute powerhouse for both 4S and 6S freestyle and racing builds. For more details, check out my review: https://oscarliang.com/holybro-kakute-h7-bt-fc-tekko32-f4-50a-65a-esc/.

XRotor Micro 60A

Tried and True

Hobbywing Xrotor G2 4in1 Esc 45a & 65a

You can find the XRotor G2 65A ESC from these vendors:

Purchase the XRotor G2 45A ESC here: 

The Hobbywing XRotor G2 45A/65A is one of the most recognizable 4-in-1 ESCs in the industry, endorsed by many top racing pilots. This feature-rich ESC offers DShot and dynamic 120kHz PWM frequency support, robust FETs, pin holes for soldering a low ESR capacitor, and the option to use either a connector for a plug-and-play setup or direct soldering to the flight controller. If budget isn’t a concern, this ESC is a strong contender. Read more here: https://oscarliang.com/hobbywing-xrotor-g2-4in1-esc-45a-65a/.

SpeedyBee BLHeli_S 55A

Cheapest Worth Having

Speedybee F405 V4 55a 4in1 Blheli S Esc Top

You can get the SpeedyBee 55A ESC from these vendors:

At just over $40, the SpeedyBee BLHeli_S 55A 4-in-1 is one of the most affordable 4-in-1 ESCs on the market, offering reliable and decent performance. I’ve personally tested this ESC and have been flying it for over a year. It’s still going strong and performing well. However, you should consider purchasing this ESC with the SpeedyBee F4 V4 FC as a stack. Together, they cost just under $70, making it one of the best value stacks available in 2024. For more details, see my review: https://oscarliang.com/speedybee-f405-v4/

Aikon AK32PRO 50A V2

Reliable 20x20mm ESC

You can get the Aikon AK32PRO 4in1 ESC from these vendors:

20x20mm ESCs are smaller and lighter but not as reliable as 30x30mm ESCs due to the larger MOSFETs on the latter. Additionally, soldering is easier on 30x30mm ESCs thanks to larger solder pads. Choose 30x30mm ESCs whenever possible; however, for lightweight racing drones or smaller drones, 20x20mm is a popular option.

Despite their compact form factor, these Aikon ESCs offer performance similar to some 30x30mm boards, with a 50A current rating per motor output and support for up to 6S. They’re small enough to fit in 3″ builds. If you ever need a 20x20mm 4-in-1 ESC for even a lightweight 5″ build, this is an excellent choice as well.

Aikon AK32 35A ESC

Reliable Single ESC

You can find the Aikon AK32 35A ESC from these vendors:

While I personally prefer 4in1 ESCs due to their ease of use, you may have reasons to choose individual ESCs. In that case, I recommend the AK32 35A ESC by Aikon. I’ve used these ESCs on a build for a couple of years without any issues, and they offer excellent reliability and performance. These are straightforward BLHeli_32 ESCs without fancy RGB LEDs, rated for 2S to 6S voltage, with a burst current rating of up to 45A.


ESC Types

There are two main types of ESCs: 4-in-1 ESC and single ESC.

4in1 ESC

A 4-in-1 ESC integrates four individual ESCs onto a single circuit board, each controlling a separate motor. Typically, a 4in1 ESC board is the same size as the flight controller board, which allows for easy stacking and streamlined installation. With fewer solder joints, they require less soldering and wiring. The 4in1 ESC usually sits beneath the flight controller and connects via a wire harness. However, if one ESC is damaged, you’ll need to replace the entire board—a trade-off between risk and convenience. However, 4in1 ESC nowadays are highly reliable so it’s generally not something to be concerned about.

Additionally, 4-in-1 ESCs offer better weight distribution due to their centralized mass inside an FPV drone frame, enhancing the drone’s responsiveness.

Two mounting patterns are available in 4-in-1 ESC boards: 30x30mm and 20x20mm. You should choose one that matches your flight controller for easy installation. However, note that larger ESCs are typically more durable and powerful, thanks to their larger FETs. For 5″ FPV drones or larger, a 30x30mm ESC is the preferred size.

It’s also becoming popular to integrate 4in1 ESC into the flight controller on a single board with 25.5×25.5mm mounting pattern. These boards are designed for smaller FPV drones, specifically 3″ or smaller cinewhoops and ultralight (aka toothpicks) that don’t generally pull a lot of amps.

Single ESC

Single ESCs control only one motor and were more popular in the past, but they have become less common in recent years as the market is dominated by 4in1 ESC.

The primary benefit of single ESCs is their ease of use and cost-effectiveness when it comes to replacement, as they can be swapped individually if damaged. However, this has become less of an advantage since ESCs are generally quite reliable these days and rarely need replacing.

Another advantage is that they get more airflow and have better cooling capabilities since they’re usually mounted on the arms.

When using individual ESCs, they typically need to be connected to a single power distribution board (PDB) or a flight controller with an integrated PDB for easy power supply.

However, individual ESCs do have some drawbacks, such as requiring more soldering and wiring, which can result in a slightly heavier drone due to the added weight of wires and the power distribution board. Additionally, the mass of the ESCs is further away from the center of the drone, which increases the drone’s moment of inertia and potentially reduces its responsiveness.


How to Choose ESC?

To select the appropriate ESC for your FPV drone, ensure you understand the requirements: the ESC should be compatible with your battery’s voltage and should handle the current draw of your chosen motor and propeller combo at 100% throttle.

Voltage Ratings

Esc Buyers Guide Voltage Rating Product Page Tekko32

Verify that your ESCs support the voltage of your battery. Using a battery voltage that’s too high for your ESC can cause damage. The majority of the ESCs these days support input voltages from a 6S LiPo battery, while some only support up to 4S (or even lower). The terms 6S and 4S refer to the cell count in your LiPo battery. If you’re unfamiliar with these terms, please refer to my LiPo battery beginner guide: https://oscarliang.com/lipo-battery-guide/#Cell-Count.

Current Ratings

Esc Buyers Guide Current Rating Product Page Xrotor Micro

The ESC current rating (or “amp rating”) indicates the maximum current an ESC can handle without damage. Keep in mind that this is NOT the amount of current pushed to the motors, it’s just a limit, so don’t worry about it being “too large”. An amp rating can never be too high, only too low.

For the typical FPV drone pilot, the current rating on most ESCs is more than sufficient. If you are building a specialized racing drone that requires extreme performance or high-speed runs, you will need to pay close attention to the ESC amp rating, along with other factors. However, under normal use, most pilots do not push their batteries hard enough to exceed the current rating of their ESCs.

There are two current ratings for an ESC: continuous and burst. The continuous current rating signifies the constant current the ESC can safely manage, while the burst current rating represents the maximum current the ESC can handle for short periods, typically less than 10 seconds.

Understanding Battery Limitations

I will try to explain why I said you don’t have to worry about current ratings in most cases.

For instance, here’s a 55A 4in1 ESC (continuous current rating).

Speedybee F405 V4 55a 4in1 Blheli S Esc Top

The 55A amp rating is for each motor, which means this 4in1 ESC is able to handle a total current of up to 220A (assuming each motor draws equal amps at 100% throttle). If you’re only pulling 100A in total, each motor is only drawing around 25A, well within the amp limit of 55A. In fact, pulling 100A is a significant load for a 5″ FPV drone, and it’s close to the limit of most LiPo batteries out there, which means they won’t sustain such high current draw long enough to actually damage your ESC. Additionally, the ESC’s burst limit is typically higher than its continuous current limit, allowing a 55A-rated ESC to handle bursts of 70A or even 80A for a few seconds. For this reason, choosing one of the recommended ESCs on our page should suffice for most 5″ FPV drones without much concern.

Durability and Weight Considerations

Modern ESCs are often marketed with higher amp ratings to indicate increased durability and resistance to voltage spikes. Although your drone may not require 50A or 60A during normal use, a higher-rated ESC may still be desirable for its increased robustness. Lower-rated ESCs, such as 30A ones, may be more susceptible to damage during crashes, despite being adequate for typical use. However, beware of the increased weight. If you are building a lightweight drone, you probably want to avoid going overboard.


ESC Firmware

In this section, I will provide an overview of the most popular ESC firmware. For a complete and up-to-date list of ESC firmware, visit: https://oscarliang.com/esc-firmware-protocols/

SimonK and BLHeli

Two of the oldest open-source ESC firmware for multirotors are SimonK and BLHeli. These are now obsolete and no longer used in modern ESCs, but they deserve an honorable mention for laying the foundation for FPV drones.

BLHeli_S and Bluejay

BLHeli_S firmware is the second generation of the BLHeli firmware, developed specifically for ESCs with faster 8-bit “Busybee” processors. This post explains how to connect, flash, and configure BLHeli_S ESCs: https://oscarliang.com/connect-flash-blheli-s-esc/

While the official BLHeli_S firmware is no longer being updated (as development focus shifted to the newer BLHeli_32), custom firmware has emerged to support hardware that comes with BLHeli_S, offering cutting-edge features and performance comparable to the latest and more expensive BLHeli_32 ESCs. A notable example is Bluejay, and I highly recommend updating your BLHeli_S ESC with Bluejay for optimal performance. Here’s a comprehensive tutorial on how to flash Bluejay: https://oscarliang.com/bluejay-blheli-s/

BLHeli_32

BLHeli_32 ESC firmware is the third and most recent generation of BLHeli. Designed specifically for 32-bit processor, it has become closed-source in this iteration. While BLHeli_32 ESC offers certain advantages and unique features to the older BLHeli_S, it is considerably more expensive and does not offer significant improvement in performance, therefore many pilots still prefer buying the cheaper BLHeli_S ESC and flash them to Bluejay.

This post explains how to connect, flash, and configure BLHeli_32 ESCs: https://oscarliang.com/connect-flash-blheli-32-esc/.

BLHeli_32 has many settings that can be confusing, which I explain here: https://oscarliang.com/best-blheli-32-settings/.

AM32

AM32 is a relatively new open-source firmware that competes with BLHeli_32. Some new ESCs are already shipped with AM32 firmware. There are pros and cons to AM32 and BLHeli_32, which you can learn about here: https://oscarliang.com/am32-esc-firmware-an-open-source-alternative-to-blheli32/.

Which ESC Firmware Should You Choose?

The performance difference between BLHeli_S ESC (flashed with Bluejay) and BLHeli_32 ESC is minimal, so you can’t go wrong with either option. Both firmware now support Bi-directional DShot, which means you can enable RPM filtering in Betaflight with either type of ESC.

BLHeli_32, as the newer generation, offers advanced features that BLHeli_S lacks, such as ESC telemetry and RGB LED support. However, these features do not impact flight performance and are thus not essential. Choose BLHeli_32 if you want a more future-proof ESC, or go for BLHeli_S if you prefer value for money.


ESC Protocols

Oneshot ESC protocol principle

Oneshot protocol

ESC protocols determine the speed of the motor signal between the FC (flight controller) and the ESC. Here is a list of ESC protocols commonly used in FPV drones, arranged from the oldest to the most recent:

Without delving too deep into technicalities, just know that DShot is currently the standard ESC protocol in FPV drones. You should always use DShot in Betaflight for optimal performance.

DShot has various speeds, indicated by the number at the end of the names. The speed you choose depends on the PID Loop Frequency set in Betaflight.

  • For 2KHz/1.6KHz, use DShot150.
  • For 4KHz/3.2KHz, use DShot300.
  • For 8KHz, use DShot600.

How to Connect ESC?

An ESC is powered directly from a LiPo battery, and the motor speed is controlled by a signal from the flight controller.

The motors are connected to the ESC through three wires. The order in which you connect the motor wires to the ESC does not matter. Swapping any two of the three wires will simply reverse the motor direction. You can also reverse motor rotation in the ESC settings, saving you from soldering. I have a step-by-step guide on how to do that: https://oscarliang.com/change-motor-spin-direction-quadcopter/.

Single ESC Wiring:

4in1 ESC Wiring:

Often, you will see a large number of capacitors on an ESC board. These are for noise filtering generated by the motors and FETs. However, regardless of the amount of filtration available on the ESC, you should always solder an additional capacitor to the power pads of your ESC. This will reduce the chance of getting a noisy FPV feed and improve flight performance. Take a look at this tutorial, where I explain why and which capacitors you should use: https://oscarliang.com/capacitors-mini-quad/.


ESC Anatomy

Now that we’ve covered ESC types, software, and requirements, let’s discuss the anatomy and components of an ESC. The essential components on an ESC are:

  • Microcontroller unit (MCU)
  • Gate driver
  • MOSFET
  • Low dropout voltage regulator (LDO)
  • Current sensor
  • Filtering capacitors

These components work together to control the speed of the motor and ensure efficient operation. I will explain what these components do in more detail below.

A 4in1 ESC basically has four ESCs integrated on the same piece of PCB. These ESCs might share the same components (such as the processor, filtering capacitors, voltage regulators, etc.), making the 4in1 ESC smaller, lighter, and overall more cost-efficient.

LDO

A low dropout voltage regulator, or LDO, is a voltage regulator used for converting battery voltage down to an acceptable level to power the microcontroller and other components.

Micro Controller

The microcontroller, MCU, or processor is the brain of an ESC, and it’s also where the ESC firmware is stored.

Gate Driver

Gate drivers are used to drive the MOSFETs in our ESC. They’re connected to the gate of a MOSFET, hence the name “gate driver.” Older ESCs use simple transistors to drive the MOSFETs. Using dedicated gate drivers improves active braking effectiveness. Instead of having separate gate drivers for the three motor phases, modern BLHeli_32 ESCs use the FD6288 IC chip by Fortior. One of these chips contains three independent MOSFET gate drivers in a single chip.

MOSFET

MOSFETs are like switches; they switch the power on and off thousands of times per second, which is how the motors are driven. Bigger MOSFETs usually mean the ESC can handle higher voltage and current, making the ESC more robust and capable of withstanding abuse. MOSFET size is especially important for high voltage rigs, such as 6S, due to the higher voltage spikes.

I have a tutorial explaining how MOSFET work: https://oscarliang.com/how-to-use-mosfet-beginner-tutorial/

Current Sensor

The current sensor measures the current that goes through the ESC and sends that information to the flight controller. This is helpful as you can display the drone’s current draw on screen in real time and see how much battery capacity has been consumed.


ESC Processor

Multirotor ESCs on the market primarily use microcontroller from ATMEL, Silabs, and ARM Cortex. Each type of MCU has unique specifications, features, and firmware support:

  • ATMEL 8-bit: Compatible with both SimonK and BLHeli ESC firmware
  • SILABS 8-bit: Supported by BLHeli or BLHeli_S
  • ARM Cortex 32-bit (e.g., STM32 F0, F3, L4): Can run BLHeli_32

ATMEL 8-bit ESCs running SimonK were more common until Silabs-based ESCs gained popularity due to the rise of BLHeli_S. In 2016, 32-bit ARM Core MCUs were introduced to ESCs, running BLHeli_32 firmware.

BLHeli_32 ESC Processors

BLHeli_32 ESCs use STM32 processors, similar to those found in flight controllers. The common processors used in ESCs are F0, F3, and F4.

Manufacturers started using more powerful F3 and F4 MCUs on BLHeli_32 ESCs since 2021, primarily due to the global chip shortage, not for their processing power. These more powerful ESCs don’t offer significant benefits over the original BLHeli_32 ESCs based on the F0 processor or older BLHeli_S ESCs (non-STM32 MCUs). The high PWM frequency (e.g., 128kHz) offered by these faster processors is mainly useful for certain type of FPV drones, for instances, cinematic flying and micro drones, where smoother motors and better efficiency are desired. This high PWM frequency doesn’t provide optimal acceleration and torque at low RPM for powerful and fast FPV drones.

To take full advantage of “variable PWM frequency by RPM” feature in BLHeli_32, smaller aircraft can benefit from the higher PWM frequency of the faster F4 processor (up to 128KHz) because they typically have much higher RPM and higher-frequency harmonics. For larger drones, such as 5″, the RPM is lower, and 96KHz or even 48KHz should suffice, making higher PWM frequency less important.

SILABS F330 and F39X Processors

F390 BLHeli-S ESC

DYS XM20A – F390

These processors are used in BLHeli_S ESCs.

SiLabs-based ESCs feature various processors with different performance levels, such as the F330 and F39X (F390/F396).

The F330 has a lower clock speed than the F39X and may struggle with high KV motors. The F39X doesn’t have these issues and supports Multishot ESC protocol and Oneshot42 seamlessly. Well-known examples include the Littlebee 20A (F330) and DYS XM20A (F39X).

Busybee (EFM8BB) Processors

BLHeli_S ESC

Aikon SEFM 20A – BusyBee

These are BLHeli_S ESC Processors.

Busybee MCUs are an upgrade to the F330 and F39X. If you currently have a BLHeli_S ESC, it probably  uses a BusyBee chip. There are two BusyBee chips:

  • BB1 – EFM8BB10F8
  • BB2 – EFM8BB21F16
  • BB51 – EFMBB51F16

Rather than using software PWM (pulse width modulation), Busybee MCUs have dedicated hardware for generating a PWM signal synced with the processor’s duty cycle, resulting in smoother throttle response. They also support DShot ESC Protocol, making them a cost-effective and efficient solution for today’s standards

Examples of ESCs that use these MCUs include the Aikon SEFM 30A and DYS XS30A.

The overall performance ratings within 8-bit processors are (from the best to the worst): BB5/BB2 > BB1 > F39X > F330 > Atmel-8-bit.

How Does ESC Work?

The ESC controls the motor by alternating currents to the motor’s stator poles in a specific sequence, creating a magnetic field that pushes and pulls on the motor’s magnets, causing it to spin. This process is called commutation, and it must be precisely timed.

User can adjust the timing to fine tune the performance of their drone, it’s called motor timing in the ESC settings.

For the motor to spin correctly, the ESC’s timing must align perfectly with the motor’s rotational speed and position. Any disruption in this timing can cause a desync, where the ESC and motor lose “communication,” leading the motor to stutter or stop completely. This is called ESC desync: https://oscarliang.com/fix-esc-desync/.

Conclusion

Armed with the essential information about ESC types, electrical ratings, protocols, and anatomy, you’re well-prepared to select the perfect ESC for your FPV drone build. Keep in mind that the majority of the latest ESCs on the market perform at a similar level, making it challenging to go wrong with any of the options mentioned in this tutorial. Focus on understanding your specific needs and preferences to find the best match for your build.

Edit History

  • 2016 – Article created
  • 2017 – updated article with info about BLHeli_32 and 32-bit processors
  • 2020 – Updated info, added ESC anatomy and connection diagrams, Added info about BLHeli_32 ESC processor
  • 2023 – Tutorial revised, updated ESC recommendations
  • May 2024 – Updated guide and product links

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40 comments

Lars 12th July 2024 - 10:36 pm

Hi,
building an y6 and i have question. Im using two 4in1 esc from t motor. i soldered 4 motor to the first esc und two motors to the second esc. the esc has numbers on it for the motor. i soldered motor 5 to second esc 1 and motor 6 to second esc 3. i did the motor reconfiguration and every motor did spin except for motor 6. do i need to solder motor 6 to second esc 2 or can i tell the esc with betaflight to use esc 3 for motor 6? I hope you got my problem. my english is not so good :D.

Reply
Oscar 13th July 2024 - 7:10 pm

You need to wire the FC’s motor 6 signal to the 2nd ESC 3, and that’s it. Maybe you didn’t change the wiring, and motor 6 is still connected to 2nd ESC 2?

Reply
Lars 15th July 2024 - 8:13 am

Thank you for your quick response. If i get you right. I need to reconfigure the communication cables between the esc and fc. The esc2, motor 3 signal needs to be wired to the fc signal input for motor 2?

Reply
Oscar 15th July 2024 - 3:33 pm

Yes.

Reply
William Melia 10th May 2024 - 5:23 pm

Hello.
The question I have is can you use an older ESC that runs on Simon K firmware to be controlled by a modern flight controller?
Thanks, Bill.

Reply
Oscar 13th May 2024 - 5:05 pm

Yes, just use an ESC protocol that is supported by the SimonK ESC, such as PWM. (I believe they also support Oneshot but it’s been so long I don’t remember exactly)

Reply
Brad 7th May 2024 - 4:44 pm

what flight controllers are the best to use with single ESCs?

Reply
Filipe 7th May 2024 - 7:48 am

Awesome post. On the speedybee esc part there’s a duplicate paragraph. Just a small thing 🙂

Reply
BACON_FPV 27th February 2024 - 7:23 pm

Great article Oscar! Just a quick potential note for your next update: I’ve been seeing the the Busy Bee 5 Family of MCUs showing up on some of the newer whoop/toothpick AIOs [specifically the EFMBB51F16 (AKA BB5)]. Side note, I haven’t had time to compare their data sheets and have absolutely no idea if there’s an actuAl benefit to using them over the BB2. I figured I’d drop a note here just in case someone has some more details or resources to share.

Thank you for everything you’ve done and continue doing! Your site is such a great resource and huge benefit to the community!

Reply
Oscar 28th February 2024 - 3:57 pm

thanks so much! I will look into that when I am doing my next update :)

Reply
Zib 26th July 2023 - 2:00 am

I enjoyed the highest recommended here Tekko32 F4 metal 65A ESC until this afternoon when I simply plugged in the same battery as usual and it exploded, releasing magic smoke and brief fire tongues. Last flight was uneventful, perfect landing, no changes to wiring. I checked and all wiring was OK, no idea what the reason was. Thankfully the FC and motors didn’t get damaged. I saw now too that similar has happened to other owners, see race day quads reviews for example. Oh well, onto a forced “upgrade” :)

Reply
Craig 29th June 2023 - 12:15 am

Hi Oscar, Another great article, but unfortunately still some of your readers (ahem) are dense enough to be a little confused.
As I understand/read it the ESC protocol is a comms protocol between the FC and ESC. Then the ESC _generates a PWM signal_ that is used to switch the battery voltage using MOSFETs, and drive the motor. As the ESC protocol can itself be encoded as PWM (e.g. for Powershot), or by some other method you have 2 sequences of modulation; FC to ESC then ESC to motor. The value going from the FC to ESC does not include the PWM encoding for the motor; the latter is calculated in the ESC. The FC just sends (“throttle is 8 out of 10 and also here’s some other relevant info”).
My questions
1. Will a motor “see” the same PWM signal arriving irrespective of ESC protocol in use? (For a constant motor speed – understood that some ESC protocols can communicate changes with less latency). If the PWM signal to the motor does vary then that means the ESC Protocol is not just a comms protocol to the FC but also a different way of generating the motor PWM?
2. Same as (1) but for Firmware – will different firmwares generate different PWMs to the motor for the same inbound FC signal? Or is the “competition” between firmwares more about additional features and compatibility etc rather than their PWM motor output.
3. If neither the ESC protocol nor the firmware make any difference to the PWM experienced by the motor (except in terms of latency from a change in input), does any thing else do so? Or is there a fixed/optimal PWM pattern to drive a motor with a given speed requirement coming from the FC.

Cheers!

Reply
DPatrick 21st May 2023 - 3:03 pm

Hi Oscar, Thank you for the article, and keep it updated.
I have the FC AIO hakrc f4126 but cannot connect the BLHeliSuite32.
Although I have upgraded it to the latest Betaflight version.
I tried different USB ports (with Lipo connected) and computers with the same result.
“ESC#1 Bootloader d #100 seems not valid for BLHeli_32”
This is a new FC, Is that an issue with the FC?
Thank you and very much.

Reply
Marc Frank 30th March 2023 - 7:38 am

No mention of AM32 and the Skystars KM55A?

Reply
Oscar 30th March 2023 - 10:12 am

In the complete list of ESC firmware article I linked to, I mentioned AM32. But it’s worth noting that this firmware is more advanced and typically not necessary for beginners to focus on.

Reply
Michael wood 1st November 2022 - 12:09 pm

Can u plse recomend a ecs for my bugs mini plse thank u

Reply
Odysseus 14th April 2022 - 8:17 am

Hi Oscar, can’t seem to get help elsewhere. I use a 60A 6s stack and run 4s. I read your article on motor output limit and decided to use my 6s batteries. My quad capacitor and FC burns after hovering for a few seconds. I thought maybe it wasn’t truly rated for 6s. I got another FC (xilo stax) and it worked fine on 4s. As soon as I pug in a 6s battery FC goes dark. Burned up again. Using a 1000uf 50v capacitor. Why is my ESC having this issue on 6s?

Reply
Radek Rezny 17th August 2021 - 8:16 pm

Hi does anyone know what is capacitance of ceramic capacitors on mamba esc Mamba f405 stack MK2, the ESC which is rated 40A. they are brown small ceramic capacitors just need to replace some but I do not know what is capacitenc woltage should be 35 or 50 v thanks

Reply
Nico 16th May 2021 - 3:45 pm

Can someone tell me if my ESC (Mamba F40HV ESC) is compatible with BLHeli_32? Cannot find any information regarding the MCU that is built in.

Reply
Oscar 16th May 2021 - 4:21 pm

No they are not compatible with BLHeli_32, only BLHeli_S.

Reply
Luca Bonucci 8th December 2020 - 11:38 am

Hi Oscar,
I have 1404 4533KV tiny trainer motors and it suggest to use 3S batteries. It also suggest a specific Betafpv AIO FC+ESC with 20A.
If the website of Betafpv now shows a similar AIO FC+ESC with 35A, would it be dangerous intall that one and try to do the build with 4S batteries? How does the choice of FC, ESC and Batteries reflect on the motors? Do the motors anyway decide how much current to withdraw? Or is that something that comes from the FC (hence me giving input to the sticks) and consequently the motors rotate faster and could even burn-out?

Reply
Hopkin 4th September 2020 - 3:34 pm

How do you tell if your 4n1 ESC has an integrated PDB? Can I assume that all 4n1 ESC has integrated PDB or is there some spec to look for. I’m building my first quad.. don’t know very much.
This is the one I have: rotorvillage.ca/aikon-ak32pin-25a-6s-4-in-1-blheli_32-esc-20×20

Reply
Oscar 4th September 2020 - 3:44 pm

All 4in1 ESC acts like PDB.

Reply
Bodie 2nd February 2020 - 9:51 am

There is one mistake in MCU names, it is not Atmel ARM 32bit MCU (these are called SAM), but only ARM 32bit Cortex MCU. ARM is vendor of core and other companies, like ST Microelectronics, NXP, Microchip (they bought Atmel) etc, add some pheripheries and build MCUs

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jack murray 24th January 2020 - 3:45 pm

hello, thanks for the great info. The latest HW30A esc has a 20-pin SSOP processor chip on it with the markings scratched out. These are like $4 from china now. I am trying to figure out what processor chip it is. Does anyone have an idea? It looks like it has 4 pads to load firmware to it.
Appreciate any info!

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Kevin Dahlquist 10th June 2019 - 6:48 am

I built a large quad intending to use two 2s batteries in parallel as I was getting a good 20+minutes of run time on old generic 30A pwm ESC’s and 2210 1000kv motors on an old CC3d FC. Now I went and upgraded to an F4 with integrated VTX, which I like overall, but I also “upgraded” ESC’s to 50A (which is overkill but it was affordable and I wanted that 8mm wide form factor).
I’ve yet to solve the mystery of why but I can now only fly if I run this setup with batteries in series for 4s (which is causes the motors to eventually overheat). I guess that’s ok if I’m going to replace the motors but things were all rated starting at 2s- it still tries to fly but lacks the power. (but I know it CAN fly this way because it did so on the original generic FC/ESC’s). I wonder if this is a variable I can limit in betaflight or Blheli32? (or on the Taranis somewhere- using an X8R Rx). Anyway thanks for any insights. I will probably change motors if I can’t figure this out. Here are the ESC’s, btw: amazon.com/iFlight-SucceX-50A-Slick-2-6S/dp/B07PBMQM6K

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Yuriy 9th April 2019 - 8:38 am

Hello! Is there any difference between f. e. 2306 2600kV with 5″ props (20Amps @ 4s) and 5010 300kV with 18″ props (20a @6s), when I chose the ESC, f. e. 30A 3-6S blheli?

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Oscar 23rd April 2019 - 4:52 pm

No, as long as the ESC meets the current requirement.

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Lucas 30th July 2018 - 3:19 pm

Hello my friend, nice post…
I have a question, when you find a 4×1 esc that says it is 20 amp… is it means that is 4 x 20 amp or 4 x 5 amp that the total is 20 amp ?

Thank you!

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Oscar 31st July 2018 - 9:30 pm

the amp rating is normally referring to each individual ESC… so it should be 4x20A

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Daniel Heeps 29th June 2018 - 6:28 am

HI,
I am building 5″ quad and would like to have a decent freestyle quad. So I ordered my FC (HGLRC F440, 4in1 esc 40amp rated) and my 1300mah 90c 4s tattu r-line batts but I couldn’t order the motors I wanted (3B 2207 2650kv motors) because they were out of stock. So while I have being waiting for them to come into stock I was researching other motors and found results that opened up another whole range of motors I could choose and now I’m lost again to which motors I should pick.
Wanted to know if you assist me picking them.
(sitting on a budget of around $130 AUD any lower for good quality would be awesome)
Thanks
Daniel.

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Oscar 30th June 2018 - 1:41 pm

Check out the Brotherhobby R6 2207 or 2306 :) I tried them and they are awesome!

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Ryan J 18th March 2018 - 2:34 pm

You should do a write up, how to make a small raspberry pi, with beta flight on it with touch screen for a in the field pocket computer you can keep in you backpack.

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Gerrit 31st October 2018 - 12:42 pm

There’s speedy bee for Android! Just need a OTG USB cable ;)

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Jim 24th May 2023 - 12:28 am

Don’t do that. Buy a speedybee adapter for ~$35 and use that with your quads instead. You can ro all the same stuff that you would with actual betaflight, but on your phone.

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Aurobindo Sangiri 31st January 2018 - 5:46 am

KDE esc’s are also there used for bigger multi copters..

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Matt 25th August 2017 - 10:43 pm

I built a quad using those emax bullet 30A esc’s and even though I was not overloading them (roughly 108A total peak) I had 4 of them catch fire. They were arm mounted (thankfully), and one even caught fire upon plug in, still in my hand. Needless to say the unburnt ones I have will remain in the drawer….

On another note I have become such a huge fan of 4-in-1’s now. I wasn’t expecting as much but they have all been super hardy (one of mine even went in the Pacific!) and fly great. I am slowly transitioning the flock over.

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Harshit Pesala 15th February 2017 - 7:12 pm

Hello I have Racestar BR2212 1000kv motor, 4 of them . I’m confused which esc to buy.Can anyone pls recommend? It would be a great help if you do so.

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Casey 8th January 2017 - 12:46 am

Hello I am a beginner builder of a zmr250. First time build. I have ordered an open flight cc3d fc. My question is, can i power my cc3d with my cc3d pbd via jumping through a 5v bec off my pdb directly? Or should I just power fc via 20amp esc with built in 5v bec. I’m trying to avoid the esc route due to weight and money saving.

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Todd 13th May 2017 - 1:46 am

On that fob there should be a 5v output that you can use to power the cc3d. I have the mini cc3d on my one and that is how I power mine. My other quad has the skyline acro and I have to run a hot wire from the pdb up under it to a 5v in on that bc it don’t have pins like most do, kinda makes it like the tower ones. Hope that helps

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