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(4) Maintaining the reference position
(a) The absolute position detector (absolute pulse coder) maintains the set reference position after the
power is turned off.
2.3.15 Floating reference position return
A floating reference position is a position of the machine used as some reference for machine operation. This
position need not be a fixed position, but can change in some cases.
An example of using a floating reference position is introduced here. In general, a lathe allows its tool to be
exchanged at any position that does not interfere with a workpiece, tail stock, and so forth. For reduced cycle
time, however, tool exchange work should be done at a position as near as possible to a workpiece. For this
purpose, the tool exchange position needs to be changed, depending on the shape of each workpiece. Before
a workpiece is machined, the tool exchange position most suitable for the workpiece can be stored as a floating
reference position in the control unit; thus, it becomes much easier to return to the floating reference position
by using G30.1.
(a) Floating reference position return end signals (FRP1, FRP2, FRP3, ...)
[Classification]
Output signals
[Function] Report the completion of controlled axis return to a floating reference position.
[Output Condition]
A floating reference position return end signal goes high when:
i. Floating reference position return (G30.1) is completed, and the current position is in the
effective area
A floating reference position return end signal goes low when:
i. The tool is moved from the floating reference position
ii. Emergency stop occurs
iii. A servo alarm is issued