Yaskawa Varispeed 626M5 - Manual (Page 134)

7.6 Winding Selection Control Precautions
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7.6 Winding Selection Control Precautions
Refer to the following precautions when designing winding selection control.
D
If the signal wire breaks or the magnetic contactor for winding selection malfunctions, the Motor will
stop, and the operation program will not proceed. At this time, perform an overtime check after the
set time, notify the operators immediately, and stop the winding selection operation by judging it to
be defective (AL-20).
D
For automatic changing using motor speed detection, winding selection will be performed whenever
the changing speed S
CHW
is passed, so the frequency of magnetic contactor operations will be high.
D
If using the main shaft drive on the lathe, automatic winding selection will be performed when chang-
ing speed is reached even during cutting. As shown in the following diagram, during rough cutting,
considerable roughness will occur during changing, but as the cutting approaches completion, the dif-
ference will be lost. As this data also makes clear, there are several characteristics in actual use, but
if accuracy in particular is essential, check the accuracy of the cut surface.
Notch
width
Cutting surface accuracy
2 mm
(0.079
inches) 10µ 200µ
3 mm
(0.12
inches) 10µ 200µ
4 mm
(0.16
inches)
10µ 200µ
5 mm
(0.2
inches)
10µ 200µ
Notch
width
Notch
width
Notch
width
* Test conditions
Cut object: S45C (φ100 round bar)
Cutting tool: Ultra-hard cutting tool
Cutting speed: 150 m/min
Cutting feed: 0.2 mm (0.0079 inches)/revolution
Fig 7.10 Surface Accuracy Data During End Face Cutting Using a Lathe
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