
7. Feed Functions
7.5 Inverse Time Feed; G93
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Detailed description
(1) Inverse time feed (G93) is a modal command. Once commanded, it is valid until feed per
minute (G94) or feed per revolution (G95) is commanded, or until a reset (M02, M30, etc.) is
executed.
(2) Command method of F command values in inverse time feed
Metric command (G21)
Inch command (G20)
During linear
mode
(G01)
Cutting point feedrate (mm/min)
Line segment length (mm)
Cutting point feedrate (inch/min)
Line segment length (inch)
During arc mode
(G02, G03)
(G02.1, G03.1)
Cutting point feedrate (mm/min)
Start point arc radius (mm)
Cutting point feedrate (inch/min)
Start point arc radius (inch)
B
0.001 to 999999.999(1/min)
C
0.0001 to 999999.9999(1/min)
D
0.00001 to 999999.99999(1/min)
Command
range
E
0.000001 to 999999.999999(1/min)
(3) The initial modal after a restart is G94 (feed per minute) or G95 (feed per revolution).
(4) The feedrate of the block inserted in tool radius compensation and corner R/C is the same
speed as the feedrate of the block immediately before it.
(5) The feedrate of the block inserted in C axis normal line control (normal line control type II) is the
same speed as the feedrate of the movement block after turning.
Precautions
(1) The initial modal after a restart is G94 (feed per minute) or G95 (feed per revolution).
(2) The F command in G93 modal is unmodal. Issue an F command for each block. The program
error (P62) will occur in blocks with no F command.
(3) The program error (P62) will occur when F0 is commanded.
(4) An F command is necessary when changing from G93 to G94/G95. The program error
(P62) will occur if there is no F command.
(5) The feed function is clamped at the maximum cutting speed. Consequently, the feed may be
slower than the commanded speed.
(6) If an extremely slow speed such as F0.001 is designated, an error will occur in the machining
time.