Siemens SINUMERIK 840Di Function Manual page 1117

2.12.22 FC 17: YDelta star/delta changeover
Description of functions
The block for star/delta changeover controls the timing of the defined switching logic such
that the changeover can be performed in either direction even when the spindle is running.
This block may be used only for digital main spindle drives and must be called separately for
each spindle.
The changeover operation is implemented via 2 separate contactors in a sequence involving
4 steps:
Step 1:
Step 2:
Step 3:
Step 4:
Fig. 2-29
Power Line Basic PLC Program (P3)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Delete the "Motor selection in progress" interface signal in the relevant axis DB (DB
31, ... DBX21.5) and connect the changeover process using "Motor selection" A (DB
31, ... DBX21.5).
As soon as the "Pulses enabled" = 0 (DB 31, ... DBX93.7) checkback signal and the
acknowledgment of the announced motor selection from the drive have appeared, the
currently energized contactor drops out.
The other contactor is energized after the time period set by the user in parameter
"TimeVal" has elapsed.
After a further delay, the changeover is signaled to the drive with "Motor selection in
progress" (DB31, ... DBX21.5).
Timing with interface signals with a delay of 500 ms set in FC 17
Detailed description
2.12 Block descriptions
2-205