HEIDENHAIN TNC 306 Technical Manual - Manual (Page 225)

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TNC 406/TNC 306 13 Datum correction 4-125
13 Datum correction
The PLC datum correction function is used to shift the zero or datum point with the PLC program.
Datum corrections are required for machines that have swivel heads.
Each axis (X, Y, Z, 4) is assigned a double word (D528 to D540) for the correction value. If a value for
the appropriate axis is entered via the PLC program, strobe marker M2716 is to be set during a
M/S/T strobe to active datum correction. The correction is computed in the actual position display.
The display then indicates the shifted coordinate system.
Example:
Actual position display for X axis without correction = 50
Correction in D528 = +20
Strobe marker M2716 set, i.e. correction is active
New actual position display X= +70
The corrections can be transferred to double words, D528 to D540 as follows:
Enter values in MP4210.0 to MP4210.47 and they will also be in D768 to D956; now copy values via
PLC program into D528 to D544.
Marker Function Set Reset
M2716 Strobe marker for datum correction PLC NC
D528 Datum correction for X axis
D532 Datum correction for Y axis
D536 Datum correction for Z axis
D540 Datum correction for axis 4
D544 Datum correction for axis 5 1)
1) only TNC 406