The status bit 'AngleDriftNotValid' in Lenze status word 2 (bit 7) is not set correctly.
The determined angle drift is always displayed as valid, even in the case of an incorrect determination.
Background:
The i950 servo inverter has so-called angle drift monitoring to detect faulty actual values.
For this purpose, two actual positions based on different "information sources" are compared. One actual position is formed on the basis of incremental signals. The second actual position is formed in the case of an absolute encoder via its digitally scannable encoder position and in the case of an incremental encoder on the basis of the zero pulse.
Both "information sources" are monitored and only if both signals are plausible, the determined angular drift is marked as valid (status word 2 bit 7). If, for example, there is a wire break on tracks A or B (radius monitoring fails), then the angle drift cannot be calculated meaningfully.
For encoders with zero pulse track, the edges of track A and track B are counted between two zero pulses and the difference to the set line count is displayed in the object "angle drift" (0x2C42:3 0x2C52:3). This can be used to determine whether erroneous pulses, e.g. caused by interference, have falsified the counter value.
