## Brushless motor stop at 58% of duty cylce

General topics and discussions about the VESC and its development.
macinblack
Posts: 2
Joined: 18 Oct 2017, 09:09
Location: Porto

### Brushless motor stop at 58% of duty cylce

Hello everyone, I use a VESC 4.12 and this motor: https://www.goldenmotor.com/hubmotors/hubmotor-imgs/HPM3000-Specs.jpg

In the BLDC Tool, I set the parameters of motor, test the hall sensors and it recognize all sensors and it works fine. When I set the duty cycle limit at 95% and turn on the motor with "up key" of my keyboard, the software increase the duty cycle but stops at 58%... I tried up the corrent and voltage, test again all sensors, but nothing works... Any help?

ThierryGTLTS
Posts: 86
Joined: 09 Aug 2017, 11:10

### Re: Brushless motor stop at 58% of duty cylce

Check first the maximum speed, but attention, electrical speed = ERPM

Erpm = (Mech.rpm) x (number of pole pair (magnets) of the motor).

You've a lot of magnets in that motor.

Have a Nice Day.

Thierry

macinblack
Posts: 2
Joined: 18 Oct 2017, 09:09
Location: Porto

### Re: Brushless motor stop at 58% of duty cylce

the question is, my motor can do 4000 RPM, but on software when I have 58% of duty cycle, I do a measure with a physical tachometer that show only 1700 RPM...

linsus
Posts: 35
Joined: 24 Apr 2016, 10:20

### Re: Brushless motor stop at 58% of duty cylce

Duty cycle doesn't have a linear behaviour with RPM from what I know?
Rather then a straight line between the axis X and Y (dutycycle vs. RPM) it should be more of a baloon shape.

rew
Posts: 943
Joined: 25 Mar 2016, 12:29
Location: Delft, Netherlands.

### Re: Brushless motor stop at 58% of duty cylce

No. RPM is linear with duty cycle. Especially at little or no load, or at a load that is proportional to the speed (RPM in this case).