Cheap 2-3S Brushless 120 Amp ESC?

[wintersdawn 176]

Anyone tried running one of these on 3S?  They are less than £20 delivered on Ebay, cheers.

 

[Silverado 281]

looks like a "clone" of Hobbywing Xerun 2.1 esc. https://www.eurorc.com/product/130/hobbywing-xerun-120a-brushless-esc-v21---blue-ftt

 

It may be really good, or it may burn the car... never been a fan of cheap esc´s. Some are fine and some ,well are something else.

 

I would suggest genuine hobbywing one, like the https://www.eurorc.com/product/14385/hobbywing-quicrun-10bl120-120a-nopeudensaadin---sensorillinen  -granted, more money then the clone.

 

or try the cheap one and let us know how it does.

[wintersdawn 176]

Cheers for the info. 

Will post back if I try one. I've only got 1 3S battery and find that 2S is plenty fast enough for bashing around forest tracks, not really into stunts and jumps.. Maybe these cheap ESC's would be ok for 2S.

[wintersdawn 176]

On 7/5/2021 at 8:26 AM, Silverado said:

looks like a "clone" of Hobbywing Xerun 2.1 esc. https://www.eurorc.com/product/130/hobbywing-xerun-120a-brushless-esc-v21---blue-ftt

If true, modelsport say this about the Hobbywing Xerun 2.1 ESC:

https://www.modelsport.co.uk/product/hobbywing-xerun-v2.1-bl-esc-120a-blue-376977

"Note:

For 4-6 cells NiMH/NiCd or 2S LiPo, the standard cooling fan needn't be changed.
For 7-9 cells NiMH/NiCd or 3S LiPo, the standard cooling fan need be changed to 12V high voltage fan."

Thanks Silverado, I think I'll skip both as I would like to buy something 3S ready.

[Falcon#5 594]

@wintersdawn, what motor are you running & in what car?

[wintersdawn 176]

1 hour ago, Falcon#5 said:

@wintersdawn, what motor are you running & in what car?

My r/c vehicle is a Maverick (by HPI) Timberwolf.  The original ESC was only rated for 2S (a fan modification was needed for 3S) but I tried 3S anyway as the vehicle was 2nd hand and I got it for a good price and I thought I could always upgrade the ESC if the original one failed.  It seemed to be ok but after a while the fan started to sound noisy, then I lost control of the vehicle and in the end it seemed to me that the ESC was telling the motor to run forward with the brake applied and subsequently the motor died, after it all got burning hot.  The original motor was a 4 pole 4000kv sensorless, brushless type.

The cheap ESC mentioned above comes sometimes as a combo with a 4 pole 3900kv motor.  I understand that as the voltage of the battery increases from 2S to 3S and above, the kv of the motor is reduced, possibly to prevent overheating so not sure a 3900kv motor is too high kv for 3S.

The Timberwolf is sort of a hybrid of an 8th scale size but due to its light-weight came with 1/10 scale electrics as standard.

 

 

[Falcon#5 594]

You might be pushing the limits of the ESC by running 3S through it?

If you want to stick with a cheap ESC, maybe look at something like 150A rated for up to 6S.

That will be able to run your 3S comfortably.

KV is a measure of how many RPM the motor will spin per Volt. More Volts = more RPM.

 

[wintersdawn 176]

9 hours ago, Falcon#5 said:

You might be pushing the limits of the ESC by running 3S through it?

If you want to stick with a cheap ESC, maybe look at something like 150A rated for up to 6S.

That will be able to run your 3S comfortably.

KV is a measure of how many RPM the motor will spin per Volt. More Volts = more RPM.

 

Cheers for the info.  Great to understand more about kv.

I have ordered a HPI Flux EMH-3S ESC, it is 80 amps (burst current 540 amps) with the following lipo specs:

2S LiPo or 6 Cell NiMH: On-Road 5.5T, Off-Road 6000 kV
3S LiPo or 9 Cell NiMH: On-Road 8.5T, Off-Road 4000 kV

As I would still like to run 2S for normal bashing with occasional 3S runs, hopefully it will do the job.  Also I have restricted space to mount the ESC and this one fits, plus the receiver box is right at the back but the channel 2 lead is long enough to route through the chassis without needing an extension.  I just have to choose the motor now, the matching one for this ESC is 4000kv and as 3S is supposed to be ok with a 4000kv motor it should be ok, but perhaps cut back on the speed runs!  My controller has a throttle control so I can restrict the power given to the motor and perhaps build it up slowly and monitor temperatures.  Also I was going to upgrade the pinion gear from 13T to 15T but understand that a lower number of teeth helps keep things cooler so will probably put the 13T in to start with.