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mycnc:mycnc_pulse_width_setup [2019/04/24 13:47]
ivan
mycnc:mycnc_pulse_width_setup [2019/04/24 13:58] (current)
ivan
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 A common procedure required for proper motor operation is selecting the appropriate pulse width for the signal going from the controller to the step/servo motor on the CNC machine. A minimum pulse width is usually noted by the motor manufacturer so as to ensure that the motor can register the signals going to it from the controller (if the pulse width is lower, then the motor cannot "​see"​ the impulse being sent from the controller to the machine). A common procedure required for proper motor operation is selecting the appropriate pulse width for the signal going from the controller to the step/servo motor on the CNC machine. A minimum pulse width is usually noted by the motor manufacturer so as to ensure that the motor can register the signals going to it from the controller (if the pulse width is lower, then the motor cannot "​see"​ the impulse being sent from the controller to the machine).
  
-As seen in the following instructions from Panasonic'​s MINAS A5-series AC Servo Motor & Driver, the pulses have to have a minimum width for the machine to register the signal, ​noted to be 0.5 μs for the 4 Mpps input and 5 μs for the 500 kpps input:+As seen in the following instructions from Panasonic'​s MINAS A5-series AC Servo Motor & Driver, the pulses have to have a minimum width for the machine to register the signal, ​ranging from 0.25 to 0.5 μs for the pulse width of the 4 Mpps input and from to 10 μs for the 500 kpps input (obtained as being double of t1 in the charts):
  
 {{:​mycnc:​pulse-width:​panasonic-2-1-v2.png|}} {{:​mycnc:​pulse-width:​panasonic-2-1-v2.png|}}
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 The value for the number of [steps / revolution] will be equal to 7812.5 steps/​revolution The value for the number of [steps / revolution] will be equal to 7812.5 steps/​revolution
 </​code>​ </​code>​
- 
  
   *As discussed earlier, the value selected on the stepper motor must be equal or smaller than the number of **[steps / revolution]** obtained from the previous step for the motor to register the signal and function properly.   *As discussed earlier, the value selected on the stepper motor must be equal or smaller than the number of **[steps / revolution]** obtained from the previous step for the motor to register the signal and function properly.
-      *//For example, if the **[steps / revolution]** value has been calculated to be 7812.5 steps/​revolution,​ then if the stepper driver allows for 3200, 6400, and 12800 steps/​revolution,​ 6400 steps/​revolution will be selected as it is the closest value that's equal to or lower than 7812.5//+      *//For example, if the **[steps / revolution]** value has been calculated to be 7812.5 steps/​revolution,​ then if the stepper driver allows for 3200, 6400, and 12800 steps/​revolution,​ 6400 steps/​revolution will be selected as it is the closest value that's equal to or lower than 7812.5 ​steps/​revolution//
  
   *Using the **[revolutions / second]** value and the updated stepper driver **[steps / revolution]** value, calculate the actual **[seconds / step]** value of the motor. This actual **[seconds / step]** value will always be equal or higher than the minimum allowable **[seconds / step]** value of the motor due to selecting a lower **[steps / revolution]** value in the previous steps.   *Using the **[revolutions / second]** value and the updated stepper driver **[steps / revolution]** value, calculate the actual **[seconds / step]** value of the motor. This actual **[seconds / step]** value will always be equal or higher than the minimum allowable **[seconds / step]** value of the motor due to selecting a lower **[steps / revolution]** value in the previous steps.
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 </​code>​ </​code>​
  
- +   *The value for the **Pulse Width** in myCNC software must be set to be equal or to the next closest value that is higher than the actual **[seconds / step]** value of the motor.
-   *The value for the **Pulse Width** in myCNC software must be equal or higher than the actual **[seconds / step]** value of the motor.+
       *//For example, if the **[seconds / step]** value was equal to 9.76 μs/step, and an ET6 or an ET7 board was used, 12 μs would be selected from the chart in the **Common Hardware Settings** tab as it is the closest value that's higher than 9.76 μs//       *//For example, if the **[seconds / step]** value was equal to 9.76 μs/step, and an ET6 or an ET7 board was used, 12 μs would be selected from the chart in the **Common Hardware Settings** tab as it is the closest value that's higher than 9.76 μs//
 {{:​mycnc:​pulse-width:​pulse-width-chart2.png}} {{:​mycnc:​pulse-width:​pulse-width-chart2.png}}
mycnc/mycnc_pulse_width_setup.txt · Last modified: 2019/04/24 13:58 by ivan