Siemens SINUMERIK 840D sl Programming Manual page 920

Work preparation
3.16 Axis couplings
grouping is interpreted as
when the grouping is switched on, the following axis traverses to its defined synchronized
position.
Variant 3:
The parameters correspond to those of variant 2 plus:
Approach mode:
Variant 3 only affects modulo following axes that are coupled to modulo leading axes. Time
optimization takes account of velocity limits of the following axis.
Further information
Description of the switch-in versions
Variant 1:
The positions of the leading axes and following axis at the instant the grouping is switched on
are stored as "Synchronized positions". The "Synchronized positions" can be read with the
system variable $AA_EG_SYN.
Variant 2:
If modulo axes are contained in the coupling group, their position values are modulo-reduced.
This ensures that the next possible synchronized position is approached (so-called
synchronization : e.g. the next tooth gap). The synchronized position is only approached if
"Enable following axis override" interface signal DB(30 + axis number), DBX 26 bit 4 is issued
for the following axis. Instead, the program stops at the EGONSYN block and self-clearing
alarm 16771 is output until the above mentioned signal is set.
Variant 3:
The tooth distance (deg.) is calculated like this: 360 * Zi/Ni. If the following axis is stopped at the
time of calling, path optimization returns responds identically to time optimization.
If the following axis is already in motion, NTGP will synchronize at the next tooth gap
irrespective of the current velocity of the following axis. If the following axis is already in motion,
NTGT will synchronize at the next tooth gap depending on the current velocity of the following
axis. The axis is also decelerated, if necessary.
920
synchronous . If the electronic gear is not in the synchronized state
The following modes can be used:
Approach next tooth gap time-optimized
"NTGT"
Approach next tooth gap path-optimized
"NTGP"
Traverse rotary axis in negative direction absolute
"ACN"
Traverse rotary axis in positive direction absolute
"ACP"
Time-optimized for programmed synchronous position
"DCT"
Distance-optimized to the programmed synchronous position
"DCP"
Programming Manual, 12/2019, 6FC5398-2EP40-0BA0
relative
NC programming