RC car guy here, I actually look at max C ratings and max amp ratings more than average. The reason being, driving wheels on the ground (grass, dirt, asphalt), you will have far more resistance than a prop moving air. A good battery manufacturer/builder has both continuous and max C rating, this is where I start. Batteries are more volatile, so I make sure the battery can handle the load first. I find ESC's not carrying a max amp rating a little disappointing, but I tend to try to overbuild a little, just to have a little cushion. On motor, i just look at KV to be honest, that is the only thing I care about. I simply match the KV to my voltage requirements and look at gearing charts to see if I can make it work. if I can, great, if not i look elsewhere for the motor. Me personally, I like higher Voltage/low KV setups Vs low voltage/high KV motors, so I lean towards lower KV motors and higher volt setups
Hi! Can you share some experiences about gearing changes when upgraded to a higher KV motor? Is there any rule of thumb such as higher Kv need higher gearing or it's just trial-and-error?
@@tuananhphamcong344 The higher the KV the higher the RPM per volt, For example a 500KV motor vs a 1200 KV say both have a max RPM of 50K, A 1200 kv can run 11s safely (technically) at 48K RPM, but the 500 KV can safely (technically) 49,950 RPM. I say technically, because they are both approaching the max RPM before something catastrophic happens (Like a Rotor exploding, or bearing failure). Me myself, I like to run my motors at half max to the highest rated RPM Available, so in this case 25k max. si i run the calculations to match 25K as close as possible. In this case the 1200 KV would be 6s max (26,640 RPM), yes it's a little faser than my max of 25K, but it's easier to buy 6s packs than 5s pack, the 500 kv would require a 14 s pack to match in RPM (25,900). as for gearing i use this scriptasylum.com/rc_speed/top_speed.html it's a gearing calculator a friend developed, it has many older vehicle specs, but if yours is not available you can just enter then in yourself, it can cover anything from geared transmissions to driect drive, so even your car isn't covered you can still use it by filling in the blanks with your numbers, it even can cover volyages Like the high V Lipo's and max volt of almost any type of battery. Of course you could just fill the numbers in yourself as well. But this is what i use on a project for estimating gearing. BTW as far as adjusting the gearing, I always went by this, "Cool motor hot esc, under geared (go up to fix) , hot motor cool esc over geared (go down to fix), both about the same temp and within specs, happy setup"
@@crazylarryjr Thank you for the clear explanation. One thing I just want to make sure is when you say "under gear", you mean the gearing is too low and should go up in pinion teeth to fix, right? and "over gear" is the opposite.
@@tuananhphamcong344 Correct Undergeared means you are running the setup at a lower or slower max speed, it is easier for the motor/esc to accelerate. The reason that is bad is the esc while most efficient at full throttle it heats up if bottomed out (the setup is at max RPM/speed). gearing up allows the esc to work properly at max with none of the issues of the bottoming out. Overgearing is the opposite effect, it's harder for the setup to accelerate. in this situation the esc is comfortable because it's working without issues, however the motor is being overworked. What you want is a compromise between, so good acceleration with good speed, yet both pieces being happy. I use a temp gun to determine temps, I usually aim for a similar temp for both the esc and the motor, you hit that you get the best compromise of everything. As far as batteries go, they can heat up as well in either situation (over/under geared). I just try to match the best battery to the setup I can, the higher the C rating the better, within your budget of course
Hi, thank you for the video. Could you please tell me how to measure the current drawn by a brushless motor (DJI M3508)? Like the wiring diagram and the current chip you would suggest. Thank you very much.
I'm wanting to design my own ESC as a personal project and planning on using mosfets to drive the circuit, is the current the motor is drawing at one time through one lead or the two leads that are providing the push/pull relationship? Trying to figure that out so I can properly size the MOSFETs.
Thanks for all your excellent and informative videos. How does spreading the work done over multiple ESCs and motors effect this equation given we still only use the one power source? Obviously faster draw down could be a factor but it could also reduce draw down given the system would likely be more efficient. I’m designing a cable cam system and I can’t for the life of me work out a mathematical formula to give me an idea of how much work the cable is doing. I’m thinking it will reduce much of the work the motor, esc and battery needs to do because it’s angularity is constant, linear and repeatable. Cable resistance, wind and payload are really the only environmental factors impinging upon the system. My dilemma is striking the balance between slow controlled movement v chasing fast moving subjects.
I linked here from your article about current and amp draw. On that page you suggest the only way to accurately know how much current is being drawn in any given RC car is to fit a data logger or analyzer to the car, could you recommend one..? I can't find anything, i was searching for something that could do the job when i found your article...
You can use telemetry sensors from the brand of your rc radio. I have used an eagle tree data logger but they may not be around any longer. There's some power meters that work well for airplane use but won't be ideal for an rc car.
Hey, great video! Would you answer me a question? Suppose my motor draws 100A max and I have a 150 amp regulator - this would be ok so far. But! - my lipo has 2000 mAh and a c-rate of 20/30. It can therefore deliver a maximum of 60A. Is the engine satisfied with what it gets from the lipo or does it want more and does it destroy/harm the lipo? I would be very grateful if you could answer this question. Greetings Stan
The motor will draw the current that it requires to rotate the load that is placed on it. Small load small current. Big load big current. Too big of a load and you will burn out the weakest link in the system. This would be your battery.
Hi. I'm trying to work out whether i can safely use a 4C battery in my RC Boat. I have a cheap RC Boat. Volantex SR65 Brushless. There isn't much information on the motor from the manufacturer, other than 2218/2700KV. The boat has a EP-20M 20A ESC controller which says it can take 2S - 4S batteries. I'm basically trying to figure out if i can run a 4C battery safely as there isn't much info about how much amps or wattage the motor or ESC can use at full load before burning out. I did the formula for 2700KV X 11.4V = 30780 rpm per volt but i've only ever used 3C batteries. Can someone please help, tell me if i can use 4C 14.8V batteries through this ESC and this 2700KV motor safely ?
I would not recommend running a 4 cell battery on a 2700Kv motor. More rpm will force you to reduce the propeller size to avoid over heating your power system.
Hi, can someone tell me. I have a small DC motor that runs on 28 volts DC. If testing using a DC power supply, I know to set my volts to 28 but what do I dial in my Amps to on the power supply?? I believe it drawas .2amps on no load. I don't want to send too much amperage to motor.
hello, i have a question on pairing esc-brushless. will this esc+motor fit on 3s correctly, or you see any problem? ESC: hobbyking.com/es_es/hobbykingr-tm-x-car-beast-series-esc-1-8-scale-150a.html or hobbyking.com/es_es/trackstar-150a-genii-1-8th-scale-sensored-brushless-car-esc-pc-programmable.html BRUSHLESS: hobbyking.com/es_es/turnigy-xk-3650-5400kv-brushless-inrunner.html?wrh_pdp=7 If you have a better option than one of these i can consider it. Thanks :) I will use it on 1/10 rwd touring
![[#2024MAMA] BIGBANG (빅뱅) - 뱅뱅뱅 (BANG BANG BANG) + FANTASTIC BABY | Mnet 241123 방송](http://i.ytimg.com/vi/EQsYfiPR9uM/mqdefault.jpg)
Thank you once again for an outstanding explanation of how "things " work. You are a pro at making the academic side understandable by the layman.
Thank You George for your comment, very much appreciate it!
I'm sorry I just have to say that you are a legend man you don't even know how much people appreciate you
Thanks for the awesome comment Ryan Shaw, means a lot to me!
Before I even watch the video, congrats on 10k subs Ryan, I'm really happy for you!
Thanks a ton!
Congratulations on a 10k subscription !!!! It's nice to see that your channel is growing!
Thank you so much 😀
Comgrats on the 10k!!!
Thank you!!
RC car guy here, I actually look at max C ratings and max amp ratings more than average. The reason being, driving wheels on the ground (grass, dirt, asphalt), you will have far more resistance than a prop moving air. A good battery manufacturer/builder has both continuous and max C rating, this is where I start. Batteries are more volatile, so I make sure the battery can handle the load first. I find ESC's not carrying a max amp rating a little disappointing, but I tend to try to overbuild a little, just to have a little cushion. On motor, i just look at KV to be honest, that is the only thing I care about. I simply match the KV to my voltage requirements and look at gearing charts to see if I can make it work. if I can, great, if not i look elsewhere for the motor.
Me personally, I like higher Voltage/low KV setups Vs low voltage/high KV motors, so I lean towards lower KV motors and higher volt setups
Hi! Can you share some experiences about gearing changes when upgraded to a higher KV motor? Is there any rule of thumb such as higher Kv need higher gearing or it's just trial-and-error?
@@tuananhphamcong344 The higher the KV the higher the RPM per volt, For example a 500KV motor vs a 1200 KV say both have a max RPM of 50K, A 1200 kv can run 11s safely (technically) at 48K RPM, but the 500 KV can safely (technically) 49,950 RPM. I say technically, because they are both approaching the max RPM before something catastrophic happens (Like a Rotor exploding, or bearing failure). Me myself, I like to run my motors at half max to the highest rated RPM Available, so in this case 25k max. si i run the calculations to match 25K as close as possible. In this case the 1200 KV would be 6s max (26,640 RPM), yes it's a little faser than my max of 25K, but it's easier to buy 6s packs than 5s pack, the 500 kv would require a 14 s pack to match in RPM (25,900). as for gearing i use this scriptasylum.com/rc_speed/top_speed.html
it's a gearing calculator a friend developed, it has many older vehicle specs, but if yours is not available you can just enter then in yourself, it can cover anything from geared transmissions to driect drive, so even your car isn't covered you can still use it by filling in the blanks with your numbers, it even can cover volyages Like the high V Lipo's and max volt of almost any type of battery. Of course you could just fill the numbers in yourself as well. But this is what i use on a project for estimating gearing. BTW as far as adjusting the gearing, I always went by this, "Cool motor hot esc, under geared (go up to fix) , hot motor cool esc over geared (go down to fix), both about the same temp and within specs, happy setup"
@@crazylarryjr Thank you for the clear explanation. One thing I just want to make sure is when you say "under gear", you mean the gearing is too low and should go up in pinion teeth to fix, right? and "over gear" is the opposite.
@@tuananhphamcong344 Correct Undergeared means you are running the setup at a lower or slower max speed, it is easier for the motor/esc to accelerate. The reason that is bad is the esc while most efficient at full throttle it heats up if bottomed out (the setup is at max RPM/speed). gearing up allows the esc to work properly at max with none of the issues of the bottoming out. Overgearing is the opposite effect, it's harder for the setup to accelerate. in this situation the esc is comfortable because it's working without issues, however the motor is being overworked. What you want is a compromise between, so good acceleration with good speed, yet both pieces being happy. I use a temp gun to determine temps, I usually aim for a similar temp for both the esc and the motor, you hit that you get the best compromise of everything. As far as batteries go, they can heat up as well in either situation (over/under geared). I just try to match the best battery to the setup I can, the higher the C rating the better, within your budget of course
Congratulations Bro! Well deserved! Keep up the great work!
Thanks! Will do!
Always informative! Congrats on your 10k subs
Thank you so much 😀
Grats on 10K subs!
Thanks Colin!
Hi, thank you for the video. Could you please tell me how to measure the current drawn by a brushless motor (DJI M3508)? Like the wiring diagram and the current chip you would suggest. Thank you very much.
Nice explanation, thank you so much
Glad it was helpful!
You deserve way more than 10k
Thanks Fraser
Very clear, thanks!!. Would it be possible to know where to find your brushless motor dyno where you show torque, RPM, thrust, power/ESC current??
I think they are called RC benchmark or something similar to that.
I'm wanting to design my own ESC as a personal project and planning on using mosfets to drive the circuit, is the current the motor is drawing at one time through one lead or the two leads that are providing the push/pull relationship? Trying to figure that out so I can properly size the MOSFETs.
Straight up awesome 😎
Hi can i put my 4500kv motor in my 3560kv esc
Congratulations!
Thank you!
can i run a 1100kv firma spektrum motor with a traxxas Velineon VXL-8S ESC, without setting the esc on fire?
get the resistance of the first phase coil. now you have given voltage and resistance you can get the initial current.
Gratz 😎
Thank You!
Thanks for all your excellent and informative videos. How does spreading the work done over multiple ESCs and motors effect this equation given we still only use the one power source? Obviously faster draw down could be a factor but it could also reduce draw down given the system would likely be more efficient. I’m designing a cable cam system and I can’t for the life of me work out a mathematical formula to give me an idea of how much work the cable is doing. I’m thinking it will reduce much of the work the motor, esc and battery needs to do because it’s angularity is constant, linear and repeatable. Cable resistance, wind and payload are really the only environmental factors impinging upon the system. My dilemma is striking the balance between slow controlled movement v chasing fast moving subjects.
I linked here from your article about current and amp draw. On that page you suggest the only way to accurately know how much current is being drawn in any given RC car is to fit a data logger or analyzer to the car, could you recommend one..? I can't find anything, i was searching for something that could do the job when i found your article...
Use a castle creations esc
@@RCexplained Any other way apart from buying another esc?
You can use telemetry sensors from the brand of your rc radio.
I have used an eagle tree data logger but they may not be around any longer.
There's some power meters that work well for airplane use but won't be ideal for an rc car.
Hey,
great video!
Would you answer me a question?
Suppose my motor draws 100A max and I have a 150 amp regulator - this would be ok so far.
But! - my lipo has 2000 mAh and a c-rate of 20/30. It can therefore deliver a maximum of 60A.
Is the engine satisfied with what it gets from the lipo or does it want more and does it destroy/harm the lipo?
I would be very grateful if you could answer this question.
Greetings
Stan
The motor will draw the current that it requires to rotate the load that is placed on it. Small load small current. Big load big current. Too big of a load and you will burn out the weakest link in the system. This would be your battery.
@@RCexplained Thank you 👍.
Great video about load of motor. Have you done a video on how gears, differential fluid and wear in car can effect this?
No I have not.
Hi. I'm trying to work out whether i can safely use a 4C battery in my RC Boat. I have a cheap RC Boat. Volantex SR65 Brushless. There isn't much information on the motor from the manufacturer, other than 2218/2700KV. The boat has a EP-20M 20A ESC controller which says it can take 2S - 4S batteries.
I'm basically trying to figure out if i can run a 4C battery safely as there isn't much info about how much amps or wattage the motor or ESC can use at full load before burning out. I did the formula for 2700KV X 11.4V = 30780 rpm per volt but i've only ever used 3C batteries. Can someone please help, tell me if i can use 4C 14.8V batteries through this ESC and this 2700KV motor safely ?
I would not recommend running a 4 cell battery on a 2700Kv motor. More rpm will force you to reduce the propeller size to avoid over heating your power system.
Hi, can someone tell me. I have a small DC motor that runs on 28 volts DC. If testing using a DC power supply, I know to set my volts to 28 but what do I dial in my Amps to on the power supply?? I believe it drawas .2amps on no load. I don't want to send too much amperage to motor.
The motor will take only what it needs.
@@RCexplained If it stalls under load and nothing is jamming it, am I looking for a motor that can draw more amps or higher voltage beyond. 28 volts?
More torque requires more amps. More RPM requires more voltage
thanks
No problem
hello, i have a question on pairing esc-brushless. will this esc+motor fit on 3s correctly, or you see any problem?
ESC: hobbyking.com/es_es/hobbykingr-tm-x-car-beast-series-esc-1-8-scale-150a.html or hobbyking.com/es_es/trackstar-150a-genii-1-8th-scale-sensored-brushless-car-esc-pc-programmable.html
BRUSHLESS: hobbyking.com/es_es/turnigy-xk-3650-5400kv-brushless-inrunner.html?wrh_pdp=7
If you have a better option than one of these i can consider it. Thanks :)
I will use it on 1/10 rwd touring
Where are said calculators?