Rockwell Automation 8520 9/Series CNC Lathe - Manual (Page 672)

Skip and Gauge Probing Cycles
Chapter 27
27-4
The format for any G37 skip blocks is:
G37 Z__ F__;
Where : Is :
G37 Corresponds to any of the G-codes in the G37 series. Use the one that is
configured to respond to the current skip signal device that is being used.
X, Z The axis on which the length offset measurement is to be taken is specified here
as either X or Z. Only one axis may be specified in a G37 block. The numeric
value following the axis name corresponds to the exact coordinate at which the
skip signal is expected to occur. This value is a signed value (+ or --) and
determines the initial direction of travel.
F The tool gauging external skip function feedrate. If no value is entered here, the
external skip function executes at either the currently active feedrate or at the
feedrate defined for it in AMP (based on whether the AMP parameter Use AMP
Skip Feedrate is set to ”NO”or ”YES”). A value entered here replaces the
currently active feedrate and supersedes the AMP-defined feedrate.
Important: The G37 series G-codes cannot be used to modify the tool tip
radius values. Only the tool length offset values can be modified.
The target offset value for these gauging operations is determined by the
currently active tool offset number
CAUTION: If modifying a tool length offset, the offset value
generated with this gauging operation is immediately loaded
into the offset table. Since this offset must be the currently
active offset, it becomes effective either immediately when the
next block is executed or delayed until the next block that
contains motion on the tool length axis is executed (when an
offset is activated is determined in AMP by the system
installer).
The G37 series of G-codes always produce linear motion regardless of the
current mode active at their execution. After their completion, the control
returns to the operating mode active before the skip block was read (G00,
G01, G02, G03).
The system installer determines (in AMP) a position tolerance for the G37
functions. This tolerance defines a legal range before and after the
coordinate position programmed with the axis word in the G37 block.
If the skip signal is received before the tool enters or after the tool exits the
position tolerance range, a PROBE ERROR occurs. This error appears on
the screen as a warning but does not place the control in E-Stop. Instead
the G37 block is aborted and program execution proceeds to the next
block. No modification of the tool offset table is performed.