8. COORDINATE SYSTEM
The point that is specific to a machine and serves as the reference of the
machine is referred to as the machine zero point. A machine tool builder
sets a machine zero point for each machine.
A coordinate system with a machine zero point set as its origin is referred
to as a machine coordinate system.
A machine coordinate system is set by performing manual reference
position return after power–on (see III–3.1). A machine coordinate
system, once set, remains unchanged until the power is turned off.
G53 _ ;
_; Absolute dimension word
When a position has been specified as a set of machine coordinates, the
tool moves to that position by means of rapid traverse. G53, used for
selecting the machine coordinate system, is a one–shot G code. Any
commands based on the selected machine coordinate system are thus
effective only in the block containing G53. The G53 command must be
specified using absolute values. If incremental values are specified, the
G53 command is ignored. When the tool is to be moved to a
machine–specific position such as a tool change position, program the
movement in a machine coordinate system based on G53.
When the G53 command is specified, cancel the tool nose radius
compensation and tool offset.
Since the machine coordinate system must be set before the G53
command is specified, at least one manual reference position return or
automatic reference position return by the G28 command must be
performed after the power is turned on. This is not necessary when an
absolute–position detector is attached.
When manual reference position return is performed after power–on, a
machine coordinate system is set so that the reference position is at the
coordinate values of (
α, β) set using parameter No.1240.
Machine coordinate system
D Selecting a machine
coordinate system (G53)
D Cancel of the
D G53 specification