Siemens SINUMERIK 840Di Function Manual page 1481

2.6.9 Referencing variants that are not supported
The following referencing variants are not supported when used with absolute encoders:
• Referencing/calibrating with encoder zero mark
• Distancecoded reference marks
• BERO with two-edge evaluation
2.7 Referencing by means of actual value adjustment
2.7
2.7.1 Actual value adjustment to the referencing measurement system
Functionality
When actual value adjustment to the referencing measuring system is performed, the
resulting absolute actual position after successful referencing of the measuring system of a
machine axis is transferred directly to all other measuring systems of the machine axis, and
the machine axis is designated as referenced:
DB31, ... DBB60.4/60.5 (referenced/synchronized 1/2) = 1
Advantage
When the machine axis switches from an explicitly referenced measuring system to the
measuring system referenced by actual value adjustment, continuous servo control is
assured (servo enable active) because the matched actual position prevents a sudden
change in actual value.
Reference Point Approach (R1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
The limit frequency corresponding to the limit speed:
MD36300 $MA_ENC_FREQ_LIMIT
is calculated as follows:
(4 * MD31020 $MA_ENC_RESOL) / (MD10050 $MN_SYSCLOCK_CYCLE_TIME *
MD10070 $MN_IPO_SYSCLOCK_TIME_RATIO)
Note
The closed-loop positioning speed:
MD35300 $MA_SPIND_POSCTRL_VELO
that is relevant for spindles must be set in accordance with the encoder limit frequency of
the absolute encoder of the spindle:
MD36300 $MA_ENC_FREQ_LIMIT (encoder limit frequency).
2.7 Referencing by means of actual value adjustment
Detailed Description
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