Maximum Encoder Limit Frequency - Siemens SINUMERIK 840D sl Function Manual

S1: Spindles
16.8 Spindle monitoring
16.8.7

Maximum encoder limit frequency

Limit violation
The maximum encoder frequency limit of the actual spindle position encoder is monitored by
the control (the limit can be exceeded). It is the responsibility of the machine tool manufacturer
to ensure that the configuration of the spindle motor, gearbox, measuring gearbox, encoder
and machine data prevents the maximum speed of the actual spindle position encoder being
exceeded.
Maximum encoder frequency exceeded.
If the spindle speed reaches a speed (large S value programmed), which exceeds the
maximum encoder limit frequency (the maximum mechanical speed limit of the encoder must
not be exceeded), the synchronization is lost. The spindle continues to rotate, but with reduced
functionality.
With the following functions, the spindle speed is reduced until the active measurement system
is operating below the encoder limit frequency again:
● Thread cutting (G33, G34, G35)
● Tapping without compensating chuck (G331, G332)
● Revolutional feedrate (G95)
● Constant cutting rate (G96, G961, G97, G971)
● SPCON (position-controlled spindle operation)
When the encoder limit frequency is exceeded
NC/PLC IS:
DB31, ... DBX60.4 (referenced/synchronized 1)
or
DB31, ... DBX60.5 (referenced/synchronized 2)
are reset for the measurement system in question and NC/PLC IS:
DB31, ... DBX60.2 (encoder limit frequency 1 exceeded)
or
DB31, ... DBX60.3 (encoder limit frequency 2 exceeded)
are set.
If the spindle is in axis mode, the maximum encoder limit frequency must not be exceeded.
The maximum velocity (MD32000 $MA_MAX_AX_VELO) must lie below the maximum
encoder limit frequency; otherwise, alarm 21610 is output and the axis is brought to a standstill.
1290
CAUTION
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions