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--- mycnc:mycnc_pulse_width_setup [2019/04/17 12:37] – ivan
+++ mycnc:mycnc_pulse_width_setup [2019/04/17 12:56] – ivan
@@ Line 1: / Line 1: @@
--===== MyCNC Pulse Width Setup ======
+===== MyCNC Pulse Width Setup ======
-==== MyCNC Pulse Width  elements ====
   *In myCNC software, navigate to **Settings**
   *Open the **Hardware** tab
@@ Line 9: / Line 8: @@
-====To Select Appropriate Pulse Width for your motor====
+====Selecting the Appropriate Pulse Width for your motor====
-A common issue with CNC machines is selecting the appropriate pulse width for the signal going from the controller to the step/servo motor on the CNC machine. The pulse impulse sent from the controller has a width that cannot be higher than the frequency at which the signals are sent to the motor, due to the signal overlap that occurs otherwise. As seen in the following instructions from Panasonic's MINAS A5-series AC Servo Motor & Driver, the pulses also have to have a minimum width for the machine to register the signal, for example, 0.25 μs for t1 of the 4Mpps input and 2.5 μs for t1 of the 500 kpps input:
+A common issue is selecting the appropriate pulse width for the signal going from the controller to the step/servo motor on the CNC machine. The pulse impulses sent from the controller to the motor have a certain width (as seen below), that cannot be too large due to the signal overlap that occurs otherwise because of each individual signal interfering with the next one. However, as seen in the following instructions from Panasonic's MINAS A5-series AC Servo Motor & Driver, the pulses also have to have a minimum width for the machine to register the signal, for example, 0.25 μs for t1 of the 4 Mpps input and 2.5 μs for t1 of the 500 kpps input:
 {{:mycnc:pulse-width:panasonic3-2.png}}
 {{:mycnc:pulse-width:panasonic3-36.png}}
-As another example, the Yaskawa's E-7-Series AC Servo Drive also imposes a similar constraint on the minimum and maximum pulse widths:
+As another example, the Yaskawa's E-7-Series AC Servo Drive also imposes a similar constraint on the minimum widths:
 {{:mycnc:pulse-width:yaskawa1.png}}
-In order to select the appropriate pulse width:
+Therefore, the pulses have to have both a minimum width, such that the motor (or the particular setting of that motor, as with the Panasonic MINAS A5-series) is able to register pulses that are sent to it, and a maximum width, such that the pulses do not overlap.
-  *Choose the speed at which your machine will move in **[meters/second]**
+**In order to select such an appropriate pulse width:**
-  *Convert the **[meters/minute]** speed with which the machine moves to the number of **[revolutions/second]** of the screw/belt/etc based on the **[meters/revolution]** value of the screw/belt on your machine
+  *Choose the speed at which your machine will move in **[meters / minute]**
-     *For example, if the desired **[meters/minute]** speed is equal to 5 meters/minute, and the **[meters/revolution]** value of the screw/belt is 5 millimeters/revolution, the **[revolutions/second]** value will be 16 revolutions/second
-  *Locate the minimum **[seconds/step]** value of your step/servo motor (the minimum time it takes the motor to process each individual impulse)
+  *Convert the **[meters / minute]** speed with which the machine moves to the number of **[revolutions / second]** of the screw/belt/etc based on the **[meters / revolution]** value of the screw/belt on your machine
+     *For example, if the desired **[meters / minute]** speed is equal to 5 meters/minute, and the **[meters / revolution]** value of the screw/belt is 5 millimeters/revolution, the **[revolutions / second]** value will be 16 revolutions/second
+  *Locate the minimum **[seconds / step]** value of your step/servo motor (the minimum time it takes the motor to process each individual impulse)
-  *Using the **[revolutions/second]** value and the minimum allowed **[seconds/step]** value of the motor, calculate how many **[steps/revolution]** the stepper driver will have to make. The value selected on the stepper motor must be equal or smaller than the number of **[steps/revolution]** obtained from this step for the motor to function properly.
-      *For example, if the **[steps/revolution]** value has been calculated to be 7800 steps/revolution, then if the stepper driver allows for 3200, 6400, and 12800 steps/revolution, 6400 steps/revolution will be selected.
-  *Using the **[revolutions/second]** value and the updated stepper driver **[steps/revolution]** value, calculate the actual **[seconds/step]** value of the motor. This value will always be equal or higher than the minimum allowable **[seconds/step]** value of the motor.
+  *Using the **[revolutions / second]** value and the minimum allowed **[seconds / step]** value of the motor, calculate how many **[steps / revolution]** the stepper driver will have to make. The value selected on the stepper motor must be equal or smaller than the number of **[steps / revolution]** obtained from this step for the motor to function properly.
-      *For example, if the **[revolutions/second]** value was equal to 16 revolutions/second and the stepper driver **[steps/revolution]** value was equal to 6400 steps/revolution, the actual **[seconds/step]** value of the motor will be equal to 9.76 μs/step.
+      *For example, if the **[steps / revolution]** value has been calculated to be 7800 steps/revolution, then if the stepper driver allows for 3200, 6400, and 12800 steps/revolution, 6400 steps/revolution will be selected.
-   *The value for the **Pulse Width** in myCNC software must be equal or higher than the actual **[seconds/step]** value of the motor.
+  *Using the **[revolutions / second]** value and the updated stepper driver **[steps / revolution]** value, calculate the actual **[seconds / step]** value of the motor. This value will always be equal or higher than the minimum allowable **[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 **[revolutions / second]** value was equal to 16 revolutions/second and the stepper driver **[steps / revolution]** value was equal to 6400 steps/revolution, the actual **[seconds / step]** value of the motor will be equal to 9.76 μs/step.
+   *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.
 {{:mycnc:pulse-width:pulse-width-chart2.png}}
       *The 12 μs corresponds to Setting 7 in the chart, thus the **Pulse width** value should be set to 7.