Define acceleration (G08/G09/G900/G901)

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

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.