Siemens SINUMERIK 840D sl Function Manual page 1337

No rapid traverse override switch available
If there is no dedicated rapid traverse override switch, you can choose between rapid traverse
override and feedrate override. The override to be active can be selected via the PLC or
operator panel front. When rapid traverse override is active, the feedrate override values are
limited to 100%.
● When the rapid traverse override is activated via the operator panel front, the basic PLC
program:
– Transfers the selection of the feedrate override for rapid traverse on the activation signal
– Transfers the feedrate override value in the rapid traverse override value:
● When the rapid traverse override is selected via the PLC, the PLC user program:
– Must set the activation signal for the rapid traverse override:
– Must transfer the feedrate override value in the rapid traverse override value:
Effectiveness of the channel-specific feedrate and rapid traverse override:
● With active G33, G34, G35:
● With active G63:
● With active G331, G332:
Reference velocity for path feedrate override
The reference velocity for the "Path feedrate override via machine control panel" can be set
differently to the standard feedrate (= programmed feedrate).
MD12082 $MN_OVR_REFERENCE_IS_MIN_FEED
Axis-specific feedrate override
An enable signal and a byte for the feedrate override factor are in the NC/PLC interface for
each positioning axis.
DB31, ... DBX1.7 (override effective)
DB31, ... DBB0 (feedrate override)
The override factor can be specified from the PLC either in the binary or gray-coded format.
The format is communicated to the NC via the following machine data:
MD12000 $MN_OVR_AX_IS_GRAY_CODE (axis feedrate override switch gray-coded)
The following permanent assignment applies to binary code:
Basic Functions
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
for the rapid traverse override:
DB21, ... DBX6.6 = DB21, ... DBX25.3
DB21, ... DBB5 = DB21, ... DBB4
DB21, ... DBX6.6 = 1
DB21, ... DBB5 = DB21, ... DBB4
Binary code
00000000
00000001
Not effective
Not effective
Not effective
Decimal
0
1
V1: Feedrates
17.4 Feedrate control
Override factor
0.00 ≙ 0%
0.01 ≙ 1%
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