Siemens SINUMERIK 840D sl Function Manual page 367

5.4.2 Measuring system error compensation (MSEC)
Function
The leadscrew error compensation function is part of the measuring system error
compensation system.
With "measuring system error compensation" (referred to below as MSEC), the base and
compensation axes are always identical. It is therefore an axial compensation for which a
definition of the base axis and compensation axis in the compensation table is not
necessary.
The principle of the MSEC is to modify the axis-specific position actual value by the assigned
compensation value in the interpolation cycle and to apply this value to the machine axis for
immediate traversal. A positive compensation value causes the corresponding machine axis
to move in the negative direction.
The magnitude of the compensation value is not limited and is not monitored. In order to
avoid impermissibly high velocities and accelerations caused by compensation, small
compensation values must be selected. Large compensation values can cause other axis
monitoring functions to output alarms (e.g. contour monitoring, velocity setpoint limitation).
If the axis to be compensated has a 2nd position measuring system, a separate
compensation table must be created and activated for each measuring system. The correct
table is automatically used when switching between measuring systems.
Activation
The "MSEC" does not become active until the following conditions are fulfilled:
● The compensation values are stored in the NC user memory and active (after power ON).
● The function has been activated for the relevant machine axis (MD32700
● The axis has been referenced
As soon as these conditions have been fulfilled, the axis-specific actual value is altered by
the compensation value in all modes and traversed by the machine axis immediately.
If the reference is then lost, e.g. because the encoder frequency has been exceeded (DB31,
... DBX60.4 or 60.5 = 0), compensation processing is deactivated.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
$MA_ENC_COMP_ENABLE [e] = 1 (interpolatory compensation)).
If a 2nd position measuring system is to be compensated, this must also be enabled with
the above machine data (e = 0: 1st measuring system; e = 1: 2nd measuring system).
DB31, ... DBX60.4 or 60.5 =1 (referenced/synchronized 1 or 2)
Compensations (K3)
Interpolatory compensation
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