Zero Point Offset - Siemens SIMATIC S5 Manual

the coordinates of the software end limit switch (end of range) plus the tool length offset
must be less than or equal to + 99.999999 m and
the coordinates of the software start limit switch (start of range) plus the tool length offset
must be greater than or equal to -99.999999 m.
Remember that the tool length offset has a sign.
The tool length offset assigned in the machine data can be called in machining programs with
to an already existing tool length offset or subtracted from it. This can be repeated. At each call,
the system checks whether the new tool length offset will exceed the limits outlined above, If
either of these limits would be exceeded, the machining program is stopped and an error mes-
sage output.
Using G40 ("clear tool length offset"), you can clear all the active tool length offsets in the whole
machining program.
An active tool length offset means that the tip of the tool approaches the specified position, inac-
tive tool length offset means that the tool holder (e.g. drill chuck) approaches the required posi-
tion,
An overall positive value for tool length offset means that the positioning module reduces the set-
point by such an amount that the position is reached with the length of the tool. When the soft-
ware limit switches are checked, the tool length offset is, however, not taken into account, i.e. the
tool holder can use the same traversing range as without an offset, (=> Section 4.3.8 "Tool
Length Offset".)
A total of four zero point offsets can be assigned in the machine data record and can be called in
machining programs using the G-functions (=> Section 2,6.6 "The G-Functions"). These can
have values throughout the whole traversing range (+/- 99.999999 m).
If a zero offset is executed, all coordinates (software limit switches, reference point coordinates
and actual value) are corrected by the amount of the offset.
When the machine data are entered, the IP247 checks whether one of the four assigned offsets
exceeds the permitted traversing range of +/- 99.999999 m. Such offsets are not executed, and
cause an error message.
Machine Data and their Structure
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