Rockwell Automation 8520-MUM 9/Series CNC Mill Operation and Programming Manual Documentation Set - Manual (Page 412)

Axis Motion
Chapter 14
14-36
In the G93 (inverse time feed) and G94 (feed per minute) modes, G04
suspends execution of the commands in the next block for a programmed
length of time in seconds.
G94G04 P__; X__; U__;
Specify the required dwell time by either a P, X, or U word in units of
seconds. It does not matter which of these three words are used, as long as
only one appears in the same block. The allowable dwell time is 0.001 -
99999.999 seconds.
When programming a dwell in seconds the system installer has the option
of writing PAL to allow a portion of the dwell to be skipped. If this feature
is used, when the appropriate signal is sent to PAL (from a switch or other
device) the control will automatically skip any portion of the dwell that has
not been executed and proceed on to the next block in the program. The
position of the axes when the skip signal is sent to PAL is recorded and
stored as system parameters #5071 - #5076 (see specifics on the G31 skip
cycles for details).
In the G95 mode (feed per revolution) G04 suspends execution of
commands in the next block for the time it takes the controlling spindle to
turn a designated number of revolutions.
G95G04 P__; X__; U__;
Specify the required dwell length by either a P, X, or U word in units of
spindle revolutions. It does not matter which of these three words are
used, as long as only one appears in the same block. The allowable range
is 0.001 - 99999.999 revolutions.
The programmable mirror image feature is used to mirror (duplicate yet
reversed) axis motion commands about some defined plane. This feature is
activated using the G51.1 code and cancelled using the G50.1 code.
Mirroring takes place about the axis position specified in the G51.1 code, it
is independent of the plane selected using G17, G18, or G19.
The format for the G51.1 code is as follows:
G51.1X__Y__Z__ ;
The axis motion commands in any following blocks are executed with the
motion direction reversed (including incremental moves) as if a mirror was
placed on the designated point parallel with the axis. The G51.1 code is
modal and remains in effect until cancelled by a G50.1 command.
14.4.1
Dwell - Seconds
14.4.2
Dwell - Number of Spindle
Revolutions
14.5
Programmable Mirror Image
(G50.1 - G51.5)