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--- mycnc:mycnc_pulse_width_setup [2019/04/17 13:31] – ivan
+++ mycnc:mycnc_pulse_width_setup [2019/04/23 09:57] – ivan
@@ Line 9: / Line 9: @@
 ====Selecting the Appropriate Pulse Width for your motor====
-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:
+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. 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:panasonic-2-1-v2.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 widths:
+As another example, the Yaskawa's E-7-Series AC Servo Drive also imposes a similar constraint on the minimum widths. The τ in the graph corresponds to the width of the impulse itself, while the T corresponds to the entire period of the signal. The manual advises a minimum τ-T of 0.125-0.5 μs, depending on the pulse train setup:
-{{:mycnc:pulse-width:yaskawa1.png}}
+{{:mycnc:pulse-width:yaskawa-2-1.png}}
-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.
+A step motor also requires a minimum pulse width, which is considerably higher than that of a servo motor (around ten to twenty times higher higher when comparing the specs for the Leadshine step motor below to the Yaskawa servo drive:
+{{:mycnc:pulse-width:step-2-1.png}}
+As such, the pulse impulses sent from the controller to the motor have to have a certain minimum width for the motor to register them. However, that signal width also cannot be too large due to the signal overlap that would occur otherwise because of each individual signal interfering with the next one. This is done by ensuring the controllers sends impulse signals at a rate that is lower than the period of the impulse at its maximum frequency, resulting in impulse signals that do not interfere with one another.
+These constraints on the minimum and the maximum pulse width create a permissible range of pulse widths for each motor depending on its hardware specifications and the particular speeds it is operated at.
 **In order to select such an appropriate pulse width:**