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Cannot reach max speed of BLDC motor

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rousha42
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Cannot reach max speed of BLDC motor

I have the VESC 6 MkV, a 36V supply, and a 900W BLDC sensorless e-bike motor. Using a simple POT in the PPM input to control speed, mapping it as duty cycle no reverse or PID no reverse (both seem to work fine, duty cycle is a little smoother). I can only get the motor to run around 2700 rpm when it should be able to reach 5000 rpm. Are there any settings in the VESC Tool that I need to change? I set the max ERPM to allow it to go to 5000 rpm, shouldn't it just work? (9 pole-pairs, so ERPM max should be 45000) I don't believe I am limiting it in any other way in VESC Tool. Could there be something I'm missing?

lurch
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max duty cycle at 95% ?

a pot must be used on adc input ?

rousha42
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Pot works fine connected to the PPM on the vesc. And yes, the max duty cycle is set to 95%. 

spacewalker
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change duty cycle to 99.% - I think is max , however you loosing nearly half  of speed , so it will not fix issue  I think.

Did VESC see  100% load ? 

Martin

frank
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If you use a poti, you need to wire it to ADC. If you use a PWM tester, you can wire it into PPM. You should check if you get 100% input signal in the wizard. Max Duty shuld be 95%. Do not raise that bar higher, since 95% is the max you can achieve with this hardwarer and firmware. You should also test how things work out if you use the controls in the VESC-Tool mobile or VESC-Tool desktop version.