Siemens SINUMERIK 840D sl, Function Manual

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Detailed description
2.1 Axis monitoring
Basic logic functions: Axis monitoring, protection zones (A3)
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Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Fault
Upon exceeding of the encoder limit frequency, the following occurs:
• Message to the PLC:
DB31, ... DBX60.2 or 60.3 = 1 (encoder limit frequency exceeded 1 or 2)
• Spindles
Spindles are not stopped but continue to turn with speed control.
If the spindle speed is reduced so much that the encoder frequency passes below the
encoder limit frequency, the actual value system of the spindle is automatically
resynchronized.
•
Axes
The following alarm is displayed:
21610 "Channel <Channel number> Axis <Axis identifier> Encoder <Encoder number >
Frequency exceeded"
The affected axis is stopped via the configured braking ramp in follow-up mode:
MD36610 $MA_AX_EMERGENCY_STOP_TIME
(Maximum time for braking ramp when an error occurs)
Note
If the encoder limit frequency is exceeded, the position-controlled machine axis must be
re-referenced.
References:
/FB1/Function Manual, Basic Functions; Reference Point Approach (R1)
2.1.5.2 Zero mark monitoring
Function
Zero-mark monitoring serves as a plausibility check for the actual values of the relevant
machine axis.
Note
The zero-mark monitoring is only active beneath the configured encoder limit frequency:
MD36302 $MA_ENC_FREQ_LIMIT_LOW (encoder limit frequency for encoder
resynchronization)
The type of zero-mark monitoring depends on the type of encoder used:
MD30240 $MA_ENC_TYPE (encoder type of actual-value acquisition)