Siemens SINUMERIK 840D sl, Function Manual

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Detailed description
2.3 Feedrate control
Basic logic functions: Feeds (V1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
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Limiting the override factor
On a binary-coded interface, the maximum possible override factors for path feedrate, axis
feedrate and spindle speed can be further limited with machine data:
MD12100 OVR_FACTOR_LIMIT_BIN (limit of binary-coded override switch)
Override active DB21, ...DBX6.6 / DB21, ... DBX6.7 / DB31, ... DBX1.7
The override values set with the selector switch on the machine control panel are
immediately active for all operating modes and machine functions, provided that IS "Rapid
traverse override active", (DB21, ... DBX6.6) "Feedrate overide active" (DB21, ... DBX6.7)
and "Override active" (DB31, ... DBX1.7) are set.
An override factor of 0% acts as a feedrate disable.
Override inactive
When the override is inactive (i.e., the above interface signals are set to “0”), the override
factor “1” is used internally on the NC (i.e., the override is 100%). In this case, the value
entered in the PLC interface has no effect.
Exceptions are the zero setting for a binary interface and the 1st switch setting for a Gray-
coded interface. In these cases, the override factors entered in the PLC interface are used.
With a binary interface, the override factor = 0. With a Graycoded interface, the value
entered in the machine data for the 1st switch setting is output as the override value. This
should be initialized with "0" .
An override factor of 0% acts as a feedrate disable.
Spindle override reference
An entry is made in machine data:
MD12080 OVR_REFERENCE_IS_PROG_FEED (override reference velocity)
to indicate whether the spindle override relates to the speed limited using MD or SD or to the
programmed speed.