Siemens SINUMERIK 840C - Manual (Page 254)

09.95 6 NC Machine Data (NC MD), NC Setting Data (NC SD)
6.5 Spindle-specific MD (spindle data)
On an oriented spindle stop (M19), the spindle is included in the position control loop. The
gain factor is defined by the steepness of the approach to the cutoff position.
If "0" is entered, the position controller loop is broken.
Notes:
The ”actual” gain factor of the gear obtained on the machine depends on several factors :
• Gain factor set for the gear
• Maximum rev/min for the gear speed
• Multgain factor (MD 468*)
• Setting of speed controller and drive
Positional tolerance for M19 443*
Default value Lower input limit Upper input limit Units
2 000 +0 720 000 units (MS)
Active on
NC Stop
On an oriented spindle stop (M19), the "SPINDLE POSITION REACHED" signal is output to
the PLC over the interface (DB31 DLk bit 4) as soon as the positional deviation is within this
tolerance. The positional tolerance is given in terms of position control resolution.
MD 443* has no effect on the positioning accuracy, because the control, in spite of the
"Spindle position reached" signal, attempts to approach the specified position with the highest
possible accuracy, unless the PLC or the NC aborts the positioning operation prematurely.
The position control for the spindle remains active until the "Acknowledge M19" signal (DB31
DRK+2) has been generated or the "Spindle controller enable" signal is revoked. For position
control cancellation, see also NC MD 520* bits 5 and 6. Position control is not cancelled by
setting the "Spindle stop" signal (see also Section entitled ”Axis (Analog) and Spindle
Installation”).
Note:
As from SW 4, for 8 gear stages
Spindle speed tolerance 444*
Default value Lower input limit Upper input limit Units
10 +0 100 %
Active on
NC Stop
In systems with analog spindle speed and spindle encoder, the difference between actual
speed and set speed is determined.
The actual speed is measured by means of the spindle encoders. The PLC is informed over
the interface (DB31) of deviations exceeding the tolerance limit of the programmed spindle
speed by removal of the "Spindle in set range" signal (DB31 DLk bit 5). This monitoring of the
tolerance limit is always in force when a specified setpoint speed causes the spindle to start
rotating, i.e. the tolerance is monitored and reported to the PLC even during the acceleration
and deceleration phases.
The tolerance (rev/min) results from the tolerance (%) entered for the setpoint speed.
(Setpoint speed - tolerance) < actual speed < (setpoint speed + tolerance)
Monitoring is discontinued at 100 %.
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50 6–69
SINUMERIK 840C (IA)