High-Pitched Noise Comes from Where?

[PoorInRichfield]

Warning! This is a dumb-@ss newbie question!

I got my first run of my new ARRMA Typhon 3S last night after finally getting batteries for it. I was running it very slowly in my basement as it was late and very cold outside. While running it, I was getting extremely annoyed by a high pitched noise that was made every time I started to apply the throttle. It sounds like it's a noise made by part of the electronics as the car is hardly moving when the noise starts. My guess is this is a common noise, but what is it coming from!??! The speed controller? The motor itself?

Granted, most people don't run their cars indoors so the high-pitched noise is probably not noticed by most, but whatever it is, it's sure annoying!

 

[jondilly1974]

Post a short video clip here. You can link to most social media sites. We don’t have direct video uploads here.

My guess is it’s the slipper clutch.

 

[PoorInRichfield]

My guess is it’s the slipper clutch.

I think you might be right. Noise sounds like it's coming from behind the motor. I've never owned a 4wd RC before, so this is new to me.

Video in my Google drive (be prepared for your ears to bleed... a little )
https://photos.app.goo.gl/LnaabhPTALLk4xyPA

 

[jondilly1974]

I think you might be right. Noise sounds like it's coming from behind the motor. I've never owned a 4wd RC before, so this is new to me.

Video in my Google drive (be prepared for your ears to bleed... a little )
https://photos.app.goo.gl/LnaabhPTALLk4xyPA

I don’t hear anything bad there. ??‍

 

[PoorInRichfield]

I don’t hear anything bad there. ??‍

I don't think there's anything "bad" or wrong with the car, I'm just wondering what the high-pitched noise is that starts as soon as the throttle is engaged (I'm assuming you're hearing that?) ? Once again, I'm a total newb... it's probably supposed to sound like it does.

 

[jondilly1974]

I don't think there's anything "bad" or wrong with the car, I'm just wondering what the high-pitched noise is that starts as soon as the throttle is engaged (I'm assuming you're hearing that?) ? Once again, I'm a total newb... it's probably supposed to sound like it does.

Yep that sounds like every 4x4 Arrma I’ve owned. You’re good to go. ????

 

[PoorInRichfield]

Yep that sounds like every 4x4 Arrma I’ve owned. You’re good to go. ????

Note to self: Do not buy 4x4 if running car indoors

 

[Camaroboy383]

It's a esc/motor whine.. any esc motor combo will make that noise..

Any particular reason your running nimh batteries? If that's what you plan to run be sure to set the esc up for that or your run times will be very very short..

 

[PoorInRichfield]

Any particular reason your running nimh batteries? If that's what you plan to run be sure to set the esc up for that or your run times will be very very short..

Reason: Fire ??? (or not wanting to see any... see my other thread)

I *think* I setup the ESC to use NiMH last night based on ARRMA's somewhat confusing owner's manual. I'm assuming the gray squares in the table below mean "factory settings" (even though the manual doesn't say that anywhere.) I changed Variable 1 to Setting 2. I'm assuming that's all I need to do(?)

 

[pomplemus]

That noise is the ESC PWM frequency (voltage modulation when driving the motor at less than full throttle), it comes from certain electronic driving components vibrating. I don't think you can do it on the BLX, but on other ESCs it's sometimes possible to change the PWM frequency if its particularly grating to your ears. Comes with the territory, very obvious especially on higher power brushless motors/ESCs.

The only subset of RC where I know significant steps are taken to eliminate/reduce it is in the crawler/scaler world, since they always move slow, and often in nice settings where you want to enjoy the sounds of nature. I believe they sometimes pad the inside of the body with sound dampening foam, or the ultimate solution is to use an ESC with FOC (field oriented control), basically an ESC with a more advanced commutation/control scheme that significantly reduces this noise, among other benefits.

Hobbywing actually has a motor/ESC all in one combo with FOC specifically for crawlers that cuts noise:

An example comparing the noise of FOC to traditional BLDC driving:

If anyone is interested in learning more about ESC PWM:

TL,DR: Its normal, and comes from the ESC.

 

[Camaroboy383]

Reason: Fire ??? (or not wanting to see any... see my other thread)

I *think* I setup the ESC to use NiMH last night based on ARRMA's somewhat confusing owner's manual. I'm assuming the gray squares in the table below mean "factory settings" (even though the manual doesn't say that anywhere.) I changed Variable 1 to Setting 2. I'm assuming that's all I need to do(?)

View attachment 105641

Yes, highlighted blocks are factory settings.. and yes variable 1, setting 2 is what you want.. ?

don't be scared of lipo's.. fire is quite rare, you typically have to puncture a cell for any of that to happen.. chances are you have had lipos on your person for years.. cell phones, vape pens, power banks, etc.. if they were as volatile as you think, there would not be warehouses full of them..?