04.97
Programming of Traversing Blocks
By means of the command "read out flying measuring value", the saved encoder actual value
can be read out.
The measuring-system displacement is maintained until it is deselected by G87 or an
operating-mode change. The existing displacement of the measuring system can be used in
different programs. The measuring system can be displaced anew, without deselecting an
existing measuring-system displacement. If the measuring system was displaced several times
without deselecting the displacement, the values will after deselection of the measuring-system
displacement refer to the original condition of the measuring system.
Special cases:
•
The block N20 only contains M-functions or a dwell time:
The axis is stopped via the brake ramp.
•
Block N20 is the program end:
The axis is stopped via the brake ramp.
Acquisition range of the fast input:
Within the gray area of the figure, a
positive edge causes a flying actual-
value setting. At the moment
➀
(breaking point), a block change
from N10 to N15 takes place. The
release for recognition of the "fast
input" is delayed until the position
100.000 is reached.
a a a a a
a a a a a
a a a a a
a a a a a
N15
a a a a a
a a a a a
a a a a a
a a a a a
N10
a a a
a a a
a a a
a a a
a a a
v
a a a a a a a a a
a a a a a a a a a
a a a a a a a a a
a a a a a a a a a
100.000
a a
a a
a a
a a
a a
s
a a a a
a a a a
a a a a
a a a a
➀
If the signal change of the fast input does not take place, the axis traverses
up to the limit switches.
The G-functions G87, G88 and G89 are only effective block by block and must be newly
selected if required.
Restrictions:
•
In a traversing block with G87, G88 or G89, only one axis may be programmed.
•
In the block following G88 or G89, too, only one axis may be programmed, and this must
be the same axis.
•
To obtain a flying block change (without stop of the axis) when changing from a traversing
block with G88/G89 to the following traversing block, G76 (chaining with quick traverse) or
G77 (chaining with axis velocity) and G64 (maximum loop-over) must be active.
•
Flying actual-value setting in synchronism is illegal.
•
Flying actual-value setting with roll feed is not possible.
©
Siemens AG 1997 All Rights Reserved 6ZB5 440-0VU02
4 – 37
WF 723 C (Programming Guide)
