Great video! The subject is explained at depth and with just the right amount of detail. Thank you.

@RCexplained

2 жыл бұрын

Thanks for the kind words Peter!

Excellent info! Thanks for sharing your knowledge 😀

@RCexplained

3 жыл бұрын

Thanks for the comment Mike!

Your explanations are very clear Thanks for the Video !

@RCexplained

2 жыл бұрын

Thanks for the kind words.

Can't thank you enough for your video. It helped explain a lot

@RCexplained

2 жыл бұрын

Glad to hear it!

Great vid ryan!

@RCexplained

4 жыл бұрын

Thank you Colin

A great explainer, thanks!

@RCexplained

Жыл бұрын

Glad it was helpful!

Solid vid thanks!

@RCexplained

3 жыл бұрын

No problem!

great explanation thanks sounds like 8k for my 4 pole boat and 12k for my 6 pole boat cheers from NZ I would love to see a test set up on a scope to show the wave forms between a cheep esc and a good one.

Good vid! Very theoretical with real world applications. Please correct me if I'm wrong but these are what i picked up: Lower PWM, hotter motor, more possible to cog. Higher pwm, cooler motorr, less cogging, hotter esc. Most of the time stock pwm doesnt need to be changed. If you do change it, compute it first. To make it short: don't change the pwm. 😁 Thanks for this vid.

@RCexplained

4 жыл бұрын

Hey James, sounds like you got it! The only thing I would say is change cog to smoothness and responsiveness issues. Generally speaking a motor would typically not have a problem with higher PWM settings at the cost of heat output from the ESC. Higher PWM settings can improve smoothness and responsiveness in the motor. Running the formula is a good way to start if considering changing the settings. This gives you an immediate baseline as to where the setting should be.

@AJ-js1yw

4 жыл бұрын

@@RCexplained oooh, so (if you increase pwm) its not necessarily a cooler motor, its the usual temperature, but a relatively higher temp esc. Also, if you lower the pwm, its not a cooler esc, just the usual temp esc, but with a relatively hotter motor. ? Okay so smoothness and responsiveness got it.

Finally. I get the answer to the questions around ESC after spending hours on Google. Awesome video. One question: How is the torque controlled? Or in other words how does the torque affect the motor RPM? Is it similar to a brushed DC motor?

@RCexplained

2 жыл бұрын

Torque is not controlled. Speed is. As the motor is loaded RPM comes down.

Hello Ryan, first of all thanks for your videos, really interesting and very well explained. Small question on this one: on the whiteboard you drew a voltage curve that is ramping up and down. Isn't this achieved using shorter PWM pulses in reality (i.e. using pulse length to get to a lower average voltage)? Or are the FETs really sending a lower voltage to the motor?

Thanks good video! I bought the castle link to adjust my esc. Do you have a video on making changes to esc settings? Praying you do lol. Anyway please stay safe and Thanks again for the great vids 💯😁

@RCexplained

4 жыл бұрын

Hey Thanks! I do not have a video going through the settings of the ESC. This is a video that will be done in time. Its possible it would be a few months out.

@furiouswolf777voodoo4

4 жыл бұрын

Ok good news. Thank you 🙂🙂

Hello For my rc tank i can change the khz with my custom elmod board Since the tank is very heavy and needs to drive slow and have a lot of torque what would be the best ? A high or a low khz ? The motor is non brushless

i have a pixhawk cube FC for my Hexacopter. i was running 200 amp madX escs' , when i switched to 500 amp Flier model escs" they wouldn't receive a signal. i checked the escs' by running a direct wire from futaba receiver to one esc and it worked fine. Why don't the bigger flier model escs receive signal from the pixhawk, but the madX escs do? any info is greatly appreciated. thanks.

Nice

Hi, Can you make a video on how to programm an esc without a program card and without a radio controller. Because I'm puzzled on how the esc is taking inputs, in the manul its given to move the throttle up later power up esc and wait for some time it will end up in program mode, but the same procedure I did it with a servo tester, for an esc it should not matter if it's a transmitter or a servo driver has long has its receiving the inputs, but for some reason my esc never went to program mode so just puzzled, it would be great if you helped me out.

how can we measure a throttle pwm signal without an osciliscope?

Hey Ryan thank you for making such informative videos I have a question though, Does motor winding type come into play when selecting PWM timing?

@RCexplained

3 жыл бұрын

Hi, thanks for the comment. Motor winding type a variable that changes the kv value. It is already captured.

So if we set the esc frequency to a lower value than it should be, what kind of troubles will we get?

Hello Ryan, really enjoyed watching your videos... I just wanna ask, does this apply too in brushed ESC...?

@RCexplained

Жыл бұрын

Yes, it's a bit different but concept is identical

Thank you for the great video! If the ESC controls only the "average" voltage (since pwn is rapid on/off) to the motor, and current is not "controlled" by the ESC but instead determined by load of the motor, then can I say that ESC does NOT directly control the power of motor nor the speed of it? BTW kv is only accurate as per voltage when there is no load, and with higher load the motor can meet the power limit sooner than reaching its kv-denoted highest speed right?

@RCexplained

4 жыл бұрын

The ESC controls the speed of the motor. kv accuracy is not required in order to control speed. The controller simply provides an on/off duty cycle, it's not a closed loop system checking and confirming that 10,000RPM was reached. A higher load could result in a slower speed at the same duty cycle.

@syncprism6283

4 жыл бұрын

@@RCexplained Understood. Thank you so much!

Thank you for another rc schooling, wondering if you mite do a comparison video between a well used motor and a new motor. Magnet strength, voltages' ability to travel intra motor when new compared to used, power feedback through the wires, how and why used motors seem to have a more static/ longer neutral point than a motor that is new. There's alot of used motors on the market for half the price of new, but the 'wear n tear' factor is not often looked at. If anybody can explain things like magnet strength depletion, a falling power curve and loss of rpm it's you ! Thanks!

@RCexplained

3 жыл бұрын

Hey Mike. Very interesting. I have always assumed that electrically the motors don't really wear.(including the magnet) Mechanically, bearings can age and wear out. How many hours of usage would be considered a "well used motor?"

I calculated from your formula 3770 x 14.8 x 4) = 11,159 Hz and having issues at 12 kHz. Is it too close to 12kHz?

Does that 12 default apply to brushless motor or also to dc motor?

@RCexplained

3 жыл бұрын

12kHz is the PWM frequency of the ESC to the brushless motor. I don't use brushed DC motors/ESC;s too often these days to comment on them.

Hi ,my motor states drive frequency is 8khz and 15 timing,my esc has 12 or 18 timing and it says pwm 8khz up to 16khz,my question is what should I set timing to 12 or 18 and is pwm frequency same as the motor drive frequency, please help

@RCexplained

3 жыл бұрын

drive frequency would be PWM frequency. Try a timing of 12 and measure performance. do the same with 18. select best

Hi Ryan, great video. I'd love to have your opinion: Just finished a new quadcopter build. I'm using Blheli32 ESCs and 935kv brushless motors. When testing the system, 3 of the motors seems to be ok but the 4th is just jumping back and forth not getting into smooth rotation to either direction. Any idea? Settings / esc problem / motor problem (all components are new). Thanks!

@RCexplained

3 жыл бұрын

Test another working motor connected to that ESC to see if it is the motor acting up. Also test another working ESC to see if it is able to spin up the hesitating motor. This should provide you with some insight to see what the problem could be. Motor vs ESC

@RechlerDudi

3 жыл бұрын

@@RCexplained That's the plan for tomorrow as it is almost midnight here 😉. Can it be a sync issue? Should I change anything on the blheli32 suit for that esc (in case it causes the same effect on a different motor?) And thanks for the fast response!

@RCexplained

3 жыл бұрын

I would not do anything until cross checked with known working equipment. If you didn't have to change anything on the 3 other setups, the fourth should be no different.

@RechlerDudi

3 жыл бұрын

@@RCexplained ok, you were right. Swapped motors and seems like it's the motor's fault. Another motor with the original esc works fine. I also tried to play with the esc parameters to get the faulty motor to work and managed to get it spinning at half throttle for a while but there were lots of vibrations and it got warm so I stopped. Do you think there is anything I can do with that motor? (Brand new, though an EMAX so not an impressive quality...)

@RCexplained

3 жыл бұрын

Spin the motor up with a drill and measure the back EMF of each phase. If they are not the same within a close tolerance, there's not much you can do. Look up my Determining Kv with a Drill Video from a couple years ago if you are unfamiliar with this process.

Hi Ryan, thanks but i think you should divide by 120 not 20. f=(RPM*p)/120, this the formula we've always used at the university. The time needed for a slot to face another pole of the same type = (60/RPM)/(p/2)= 120/(p*RPM)=120/(p*KV*V). You invert it and you obtain the frequency

@RCexplained

3 жыл бұрын

Hi Jean, in the formula that you have used, you have not used the commutation steps per electrical revolution. As a result, when calculating your PWM frequency, it will result in a lower frequency then the commutation frequency. This is the opposite relationship that you want. There is not much really to lose with a higher PWM frequency but that is not the case with a lower PWM frequency.

Hi I have a pwm signal controller. It has a digital display(that's necessary for my project). It has a frequency choice and duty cycle (I get confused between these two). Can I attach the pwm signal to the ESC controller for brushless motor? The PWM controller has a +- voltage output. I need it for a mini blower fan. The ESC 3 wires connect to the brushless motor, but not sure how I should connect the pwm signal to the ESC

@RCexplained

3 жыл бұрын

In the video we were talking about the output PWM frequency that the ESC uses to drive the motor. I don't remember touching on the input to the ESC as it seems you are interested in. Generally the input requirement is about a 4-6V peak to peak square wave pulse. Pulse length or duration is 0.9mS to 2.1mS. The pulse refreshes at 50Hz or 20mS.

@vahagnmelikyan2906

3 жыл бұрын

@@RCexplained so what would happen if I connect 5v dc input into the ESC speed controller without pwm, or any frequency. Wouldn't the esc still work to control the motor?

@RCexplained

3 жыл бұрын

@@vahagnmelikyan2906 to control the esc you would have to supply the correct signal through the 3 lead radio wire of the esc.

Not sure if you still answer old video questions. My esc came set at 1000 hz. I'm running a 3300 kv 4 pole on 3s it came to 7326 so should I change it to 8 kHz?

@RCexplained

2 жыл бұрын

I dont get to all the questions. Confirm that the 1000Hz is the pwm frequency. I haven't seen one being so low before. Most escs are at atleast 8000hz or 12000hz. Change to 8khz if confirmed.

@revee1000

2 жыл бұрын

@@RCexplained thank you . On my program sheat the adjustability is from 1 thru 8 starts at 16KHz to 125 Hz . It is a cheap 80 amp esc. I don't have any equipment to test it

@RCexplained

2 жыл бұрын

@@revee1000 16KHz will be fine.

From where do we get that constant (20) that you use to divide the PWM frequency formula? If I plug in your formula for a 4S (14.8V) whoop and a 4500 kV motor I get 46.6 kHz optimal PWM Frequency. So for whoops, 48kHz is the right frequency?! Not all ESCs support this.

Awesome! I thought that ESC were controlled using PPM instead of PWM signals. Is PWM the correct type of signal to input in the signal cable of the ESC?

@RCexplained

3 жыл бұрын

Note that the PWM frequency mentioned in the video is for the output to the motor.

Can you turn this theory into practice using a RC dyno with different motors for comparisons? 👍

@RCexplained

4 жыл бұрын

Hey Greg, that's the plan for many of the videos that have been posted. I want to demonstrate these theoretical approaches using the appropriate motors etc. I have some limitations to work through until I can get there. A major limitation is equipment. A good example is even this particular video. I do not have a setup that actually requires a higher PWM setting then factory.

HEY NICE VIDEO !! I HAVE A DOUBT IF WE HAVE 24 VOLT BATTERY , DOES 100% THROTTLE MEAN 100% DUTY CYCLE MEANING 24 VOLTS APPLIED ?

@RCexplained

4 жыл бұрын

24v is always the applied voltage from the ESC if the battery is 24v, however the motor will "see" the average based on the duty cycle. At full throttle, duty cycle is 100%, motor sees source voltage.

@abhijeetdhillon9591

4 жыл бұрын

@@RCexplained SO 50% THROTTLE MEANS 12 VOLTS TO MOTOR?

Why the division by 20 in the formula for frequency?

@RCexplained

4 жыл бұрын

I can't remember the formula off the top of my head, however, its the amount of commutation cycles with a factor to get the PWM frequency away from this value.

I have an edf motor that is a bit puzzling. 2250kv, 6s 22.2v, 12 poles. Would this require an esc that can to 32k?

@RCexplained

2 жыл бұрын

Yes most high performance motors used in high powered EDFs are inrunners with a 4 pole rotor.

@96vmax4

2 жыл бұрын

@@RCexplained my edf units use a 12 pole out runner

@96vmax4

2 жыл бұрын

@@RCexplained they are jp 70mm 6s edf units. For some reason jp says they require certain esc to run. Is that due to and the extremely high switching rate?

Sooooo.... What I got from this is I could use brushed ESC to drive a DC induction 12v automotive fuel pump with PWM, so long as I converted a pressure signal to PWM? What frequency is the output signal of the receivers typically? (I could do brushless but I'm not a baller like that, the point is to be able to run a fat, cheap, single pump in the factory bucket, without it drawing 20+amps all friggen day...) Could also step up the voltage based on this. Essentially replicate what most modern fuel systems do for pressure control, but still have a regulator on the return. (it would just be set slightly higher than the pump's control pressure, as a default, where in the pump would be running wide open. Car would run rich enough it would be obvious something isn't right, but wouldn't fry a piston, and would be driveable to get to a safe place. Or could have a relay that just kills the pump. Is this a reasonable application for an old ESC? curious how reliable they would be. Haven't had a change to scope a few OEM FPCMs to see what they like for input to kick on.

@RCexplained

2 жыл бұрын

The video discusses the output from esc to motor. Not receiver to esc. A simple servo tester can control an esc.

This seems to apply to planes and cars not necessarily quadcopters. My micro quads use 24khz or 48khz. In fact the higher 48khz is MORE efficient for very small, very high kv setups.

@RCexplained

3 жыл бұрын

What did you calculate using the formula?

Please confirm, My helicopter motor is 520KV , Magnet Poles 10 , 12s lipo 44.4V. So 44.4 X 520 X 10 = 230 880 / 20 = 11.544, so my PWM should be 12Khz? Align T-Rex 800MX Brushless Motor(520KV) + Castle Phoenix Edge HV 120 Brushless ESC

What's the point in all the other settings then if they don't do anything, surely the manufacturer wouldn't let you change them if they made no difference?

@RCexplained

4 жыл бұрын

Hey Lawrence, from my own (limited) experience, I have not come across a setup that requires a different PWM setting on the ESC. Surely there are many setups that require different settings, however, it will be a low percentage overall. I ran through the calculation in the video of a couple of my own setups, but I'm sure I can find values that will theoretically require a different setting. Have you ever required to change the PWM setting?

@LawrenceTimme

4 жыл бұрын

@@RCexplained I don't think any of my escs have it as a changeable setting, but on computers I know you can change the pwm frequency for the VRM which powers the cpu. When overclocking it can increase the stability a lot under higher current and voltage. The VRM on the motherboard does run warmer because of this. I have seen some more race oriented escs you can change the pwm frequency separately on both the brake and normal forward driving of the car.

@shadow7037932

4 жыл бұрын

​@@RCexplained For RC cars, PWM frequency doesn't really matter much like you said. But for RC quads, especially racing quads where very fast and small changes are made by the flight controller, a higher PWM setting can help depending on motor, ESC, flight controller combination.

@RCexplained

4 жыл бұрын

@@shadow7037932 yes, formula would help out with the high RPM and Pole count that are commonly found in quads.

This formula for the PWM frequency says nothing else than you should have at least 1 pwm pulse within 1 PM pole N-S transit along of 1 stator pole. I personally would rather work with at least 2 or 4 pulses within 1 PM pole N-S transit to get a smoother motor behavior.