12 Functional Descriptions 08.96
12.3 Endlessly rotating axis (SW 4 and higher)
12.3 Endlessly rotating axis (SW 4 and higher)12.3.1 Corresponding data
• NC MD 330 (dead time compensation for dwell)
• NC MD 5024 Bit 1 (G200 after G [..] 105, G [..] 119)
• NC MD 5025 Bit 1 (axis-specific G functions to PLC)
• NC MD 5025 Bit 6 (activation of endlessly rotating axis)
• NC MD 521* Bit 2 (power-up as C axis)
• NC MD 584* Bit 0 (initial position of simultaneous axis)
• NC MD 1152* (speed tolerance of an endlessly rotating axis)
• Alarm 1300* (programmed axis is not a rotary axis)
• Alarm 1304* (axis rotates endlessly)
• Alarm 1308* (simultaneous axis incorrectly programmed)
• Alarm 1312* (simultaneous axis incorrectly programmed)
General
With SW 4 and higher, a rotary axis can also be operated as an endlessly rotating
axis (ERA) 1).
The scope of functions of the existing rotary axis remains unchanged.
The "Endlessly rotating axis" functionality corresponds to that of a simultaneous axis. The
ERA is not restricted by block limits, in other words, it continues to rotate in the desired
direction at the desired speed provided no stop criterion is fulfilled (shutdown, axis reset,
error).
Furthermore, shutdown can be effected with a specified position.
The characteristics of the "Endlessly rotating axis" are as follows:
• Axis is generally in position control mode
• Speed setpoint resolution corresponds to set position control resolution
• Feedrate input in input system * 10
Example: If the input system is set to 10-4 by means of machine data, then the smallest
programmable feedrate unit with G94 is active is calculated as follows:
10
-4
mm * 10 rev/min = 10
-3
mm/min.
The "Endlessly rotating axis" function is programmed by means of new axis-specific G
commands.
It can be controlled from several channels independently of the selected operating
mode.
• The feedrate of the endlessly rotating axis is weighted with the axis-specific override.
1) ERA is the abbreviation for endlessly rotating axis.
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SINUMERIK 840C (IA)