Siemens SINUMERIK 828D Function Manual page 1394

V1: Feedrates
17.4 Feedrate control
Spindle-specific override
One enable signal and one byte for the spindle override factor are available in the NC/PLC interface for each
spindle.
DB31, ... DBX1.7 (override effective)
DB31, ... DBB19 (spindle override)
The override factor can be specified from the PLC either in the binary or gray-coded format. This format being
used is communicated to the NC via the following machine data:
MD12060 $MN_OVR_SPIND_IS_GRAY_CODE (spindle-override switch is gray-coded)
The following permanent assignment applies to binary code:
Binary code
00000000
00000001
00000010
00000011
00000100
...
01100100
...
11001000
For gray coding, the override factors corresponding to the switch position should be entered in machine data:
MD12070 $MN_OVR_FACTOR_SPIND_SPEED [n] (evaluation of spindle override switch).
Thread cutting
The spindle override is active for: G33, G34, G35, G331, G332
The spindle override is inactive for: G63
Limiting the override factor
For binary-coded override factors, the maximum possible overrides for path feedrate, axis feedrate and spindle
speed can be limited:
MD12100 $MN_OVR_FACTOR_LIMIT_BIN (limit for binary coded override switch)
Override active
For overrides that have been enabled, the specified override values entered via the machine control panel
become immediately active in all operating modes and machine functions.
1394
Decimal
0
1
2
3
4
...
100
...
200
Override factor
0,00 ≙ 0%
0,01 ≙ 1%
0,02 ≙ 2%
0,03 ≙ 3%
0,04 ≙ 4%
...
1,00 ≙ 100%
...
2,00 ≙ 200%
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions