Siemens SIMATIC FM 453, Manual

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10-7
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
This changes blocks on-the-fly from N10 to N15, with G89 causing move-
ment in a positive direction and G88 causing movement in a negative direc-
tion at the speed programmed in N15.
The axis now travels in the specified direction until a positive edge change
occurs at the digital input. This triggers the following responses:
S
Block change on-the-fly and immediate processing of block N20
S
Set actual value on-the-fly to the block position from N15 (50 in the ex-
ample), and resulting shift of the coordinate system
S
Save current actual value.
The programmed position in block N20 refers to the shifted coordinate sys-
tem.
At the block change from N20 to N25, G87 cancels the shift of the coordinate
system and causes reference-measure programming to the block position
of N25.
The saved actual value can be read out with “Actual value block change.”
The shift of the coordinate system is maintained until it is canceled by G87
or by a mode change. It is possible to use the existing shift of the coordinate
system in different programs. The coordinate system can be shifted again
without previously canceling an existing coordinate system shift.
G88, G89 can be programmed multiple times. The shift in each case refers
to the original state. The software limit switches are always shifted concur-
rently.
If the signal change of the digital input does not occur, the axis runs until it
reaches the limit switch.
Note
The G functions G87, G88 and G89 take effect only on a block-by-block
basis and must be reselected if necessary.
Notes to the
Example of Set
Actual Value
On-the-fly
Writing Traversing Programs