Technical Manual TNC 360 - heidenhain - DR. JOHANNES ...

A different gear range from that which is selected by the NC can be activated by the PLC setting
Markers M2104 – M2106 and Marker M2814. Marker M2814 is reset by the NC after the gear
change.
Check that the spindle speed selected by the PLC is within the spindle speed limits of the selected
gear range.
The PLC program must transfer the gear code to the machine. The NC waits for the
acknowledgment signal "Gear change completed" (M2480) before continuing the program . As soon
as marker M2480 is set by the PLC the NC resets the strobe signal M2043. The marker M2480 may
only be set in one PLC cycle.
Set Reset
M2043 Gear-code change signal NC NC
M2480 Acknowledgment PLC PLC
“Gear change completed”
M2104 1st bit gear code for S analog (lsb) PLC PLC
M2105 2nd bit gear code for S analog PLC PLC
M2106 3rd bit gear code for S analog (msb) PLC PLC
M2814 Activation of a gear range and spindle speed PLC NC
via PLC
D356 Programmed spindle speed NC
D756 Set spindle speed from the PLC; NC, PLC
programmed spindle speed
W256 G code for S analog NC
An alternating S-analog voltage can be produced for changing gear. For this purpose the marker
M2490 and the marker M2491 must be alternately set and reset by the PLC. This may be achieved
by interrogating a particular timer in the PLC program. The markers M2490 and M2491 are reset to
stop the spindle. The output voltage is defined by MP3240.2.
MP3240.2 Jog voltage for gear change
Input value 0 to 9.999 [V]
Set Reset
M2490 Spindle rotation left (for gear change) PLC PLC
M2491 Spindle rotation right (for gear change) PLC PLC
The direction of spindle rotation after the gear change is determined by the PLC program with the
markers M2485 to M2487 (see "Direction of spindle rotation").
Machine parameter MP3030 can be used to determine whether an axis halt should occur on a TOOL
CALL with only a spindle speed output.
4-86 TNC 360 4 Spindle 8/95