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--- mycnc:mycnc_pulse_width_setup [2019/04/17 12:56] – ivan
+++ mycnc:mycnc_pulse_width_setup [2019/04/17 13:31] – ivan
@@ Line 9: / Line 9: @@
 ====Selecting the Appropriate Pulse Width for your motor====
-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:
+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. 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 would occur 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}}
@@ Line 18: / Line 18: @@
 {{:mycnc:pulse-width:yaskawa1.png}}
-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.
+As such, 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.
 **In order to select such an appropriate pulse width:**
@@ Line 30: / Line 30: @@
-  *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.
+  *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.
+     *For example, if the minimum allowable pulse width on the motor is 8 μs/step, and the machine will produce 16 revolutions/second, then the maximum value for the **[steps / revolution]** will be around 7800.
+  *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 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 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.
-      *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 **[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 9.8 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.
+      *For example, if the **[seconds / step]** value was equal to 9.8 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 9.8 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.
+         *NOTE: The first value in the **Pulse Width** line refers to the first four axes of the controller (for example, the horizontal X and Y axes), while the second value refers to the other two axes of the controller (for example, the vertical Z axis). These values are set to be different if the controller used on the vertical axis is separate from that used on the horizontal, and are left the same if only one controller is used.
 {{:mycnc:pulse-width:pulse-width-chart3.png}}
     *The pulse width setup is now complete.