Wuhan Huazhong Numerical Control Co., Ltd HNC-18iT, Руководство по программированию

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5. Coordinate System
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5.1 5.1 5.1 5.1 Reference Reference Reference Reference Position Position Position Position Return Return Return Return (G28) (G28) (G28) (G28)
Programming Programming Programming Programming
G28 X(U)_ Z(W)_
Explanation
Explanation Explanation
Explanation of
of of
of the
the the
the parameters
parameters parameters
parameters
X, Z Coordinate values of the intermediate point in absolute command
U,W Coordinate values of the intermediate point with reference to the starting point in
incremental command
Function Function Function Function
The tool is moved to the intermediate point rapidly, and then returned to the reference point.
Z
Z
Z Z
X X X X
Reference position
Intermediate position
Figure 5.1 Reference Position Return
Note:
Note: Note:
Note:
1) In general, G28 is used to change tools or cancel the mechanical error. Tool radius
compensation and tool length compensation should be cancelled when G28 is
executed.
2) G28 can not only make the tool move to the reference point, but also can save the
intermediate position to be used in G29.
3) When the power is on and manual reference position return is not available, G28 is
same as the maunaul reference position return. The direction of this reference
position return (G28) is set by the axis parameter – reference approach direction.
4)
G28 is one-shot G code.