Siemens SINUMERIK 840D Function Manual page 472

M3: Coupled axes
14.4 Electronic gear (EG)
IS "Enable following axis override" DB31, ... DBX26.4
In the case of the commands EGON() and EGONSYNE(), the "Enable following axis override"
signal must be present for the gear to synchronize to the specified synchronization position for
the following axis. If it is not present, alarm 16771 "Override movement not enabled" is issued.
If the signal is present, the following axis travels to the synchronized position with the calculated
acceleration and at the velocity set for the approach mode.
Further monitoring signals
Machine data MD37550 $MA_EG_VEL_WARNING allows a percentage of the speeds and
accelerations to be specified in the following machine data MD32000 $MA_MAX_AX_VELO
and MD32300 $MA_MAX_AX_ACCEL, with reference to the following axis, which results in the
generation of the following interface signals:
IS "Speed warning threshold" DB31, ... DBX98.5
IS "Acceleration warning threshold" DB31, ... DBX98.6
Machine data MD37560 $MA_EG_ACC_TOL allows a percentage with reference to machine
data MD32300 $MA_MAX_AX_ACCEL of the following axis to be defined, and the IS signal
"axis accelerates" DB31, ... DBX99.3 to be generated.
Request synchronism difference
1. The result of the synchronism difference calculation can be read as an amount in the part
program with system variable $VA_EG_SYNCDIFF. The relevant value with sign is
available in the system variables $VA_EG_SYNCDIFF_S. The following meanings apply:
● Negative value (in positive traverse direction for lead and following axis): The following axis
lags behind its calculated setpoint position.
● Positive value (in positive traverse direction for lead and following axis): The following axis
leads before its calculated setpoint position (overswing).
The amount of the synchronism difference with sign corresponds to the system variables
without sign from $VA_EG_SYNCDIFF.
$VA_EG_SYNCDIFF[ax] = ABS($VA_EG_SYNCDIFF_S[ax])
Block change mode
1. When an EG axis group is activated, it is possible to specify the conditions under which a
part program block change is to be executed:
2. The specification is made with a string parameter with the following meaning:
3. "NOC": Immediate block change
4. "FINE": Block change if "Fine synchronism" is present
5. "COARSE": Block change if "Coarse synchronism" is present
6. "IPOSTOP": Block change if "Setpoint synchronism" is present
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Axes and spindles
Function Manual, 06/2019, A5E47437747B AA