Siemens SINUMERIK 840D sl Function Manual page 1622

Detailed Description
2.1 Spindle modes
Spindle actual speed display and spindle behavior with G96, G961
DB31, ... DBX61.4 (axis/spindle stationary)
Machine data:
MD36060 $MA_STANDSTILL_VELO_TOL
defines the speed at which the spindle is considered "stationary".
The speed set in the machine data should be dimensioned
so that NC/PLC IS:
DB31, ... DBX61.4 (Axis/Spindle stationary) is sure to be
pending on standstill.
If the NC/PLC interface signal:
DB31,...DBX61.4 (Axis/Spindle stationary)
registers and no position control is active for the spindle then the actual speed is shown as
zero on the operator interface and is read as zero by the system variables $AA_S[n].
References:
/FB1/Descriptions of Functions, Basic Machine; Various Interface Signals and Functions (A2)
Spindle behavior with G96, G961
Constant cutting rate
• At the start of machining (transition from G0 to Gx) and after NC stop, G60 (exact stop,
reached the speed setpoint tolerance range before starting the path.
NC/PLC IS:
DB31, ... DBX83.5 (nAct = nSet)
is then set.
• NC PLC IS:
DB31, ... DBX83.5 (nAct = nSet)
and
DB31, ... DBX83.1 (Setpoint speed limited)
are also set to defined values even if severe speed changes are specified
(transverse axis travels towards position 0).
• If the speed drops below the minimum speed
or when NC/PLC IS:
DB31, ... DBX61.4 (Axle/Spindle stationary)
is detected, NC/PLC IS:
DB31, ... DBX83.5 (nAct = nSet)
• A path operation, which has started (G64, rounding), is not interrupted.
Machine data:
MD35500 $MA_SPIND_ON_SPEED_AT_IPO_START
can also influence spindle behavior significantly.
12
modal) and G09 (exact stop, non-modal) the system waits until the actual speed has
is reset (e.g., for an emergency machine strategy).
Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0