Define acceleration (G08/G09/G900/G901)

Notice

notice

Acceleration definition operations are only effective in connection with the linear slope.

G08

Acceleration at block start

(modal, initial state)

G09

Deceleration at block end

(non-modal, effect dependent on G901/G900)

G901

Deceleration after block end; can be cancelled blockwise by G09

(modal)

G900

Deceleration at block end independent of
G09 modal active

(modal)

If two consecutive NC blocks are programmed at different feedrates, a "soft" adaptation occurs at the block limit. As specified by G08, an acceleration takes place only at block start. G09 specifies that a deceleration to the feedrate of the next block should already occur at the end of the current block.

G09 is the default setting at program start. The G901 function defines the default setting for deceleration only after block end. The inverse G function G900 is a change-back function and is equivalent to the channel default setting.

Attention

attention

During transition from G00 to G01, G02 or G03, G09 is always active, i.e. deceleration at block end down to the velocity of the following block.

If the path velocity limit is already achieved while G901 is active, the velocity of the following block is reached at block end, i.e. then G901 is not effective.

Programing Example

prg_example

Define acceleration (G08/G09/G900/G901)

Acceleration at block transition in initial state (equiv. to G08).

N10 G01 X500 F400

N20     X900 F1000

Acceleration at block transition in the default state (corresp. to G08)
Acceleration at block transition in the default state (corresp. to G08)

Programing Example

prg_example

Define acceleration (G900/G901)

Deceleration at block transition with G901 and G900

N10 G01 G901 X500 F1000

N20          X900 F400

Deceleration at block transition with G901 and G900
Deceleration at block transition with G901 and G900

N10 G01 G900 X500 F1000

N20          X900 F400

Deceleration at block transition with G901 and G900
Deceleration at block transition with G901 and G900

Programing Example

prg_example

Define acceleration (G900/G901)

Combination of G09 with G901 and G900.

N10 G01 G901 X200 F2000

N20     G09  X400 F1600

N30          X600 F1200

N40     G900 X800 F800

N50          X1000 F400

:

Combination of G09 with G901 and G900
Combination of G09 with G901 and G900