F07555 — Drive encoder: Configuration position tracking

F07555 reports that the position tracking configuration of a drive encoder is not supported. Position tracking can only be activated for absolute encoders, and for linear axes it is not possible to activate position tracking for the load gear and the measuring gear at the same time. Which concrete cause applies is encoded in the fault value that the drive stores in r0949. Depending on the drive configuration, the same condition can also be signaled as an alarm; as an alarm it triggers no reaction and requires no acknowledgement.

• Position tracking was activated although the connected encoder does not support it: position tracking can only be activated for absolute encoders.
• For a linear axis, position tracking was activated for the load gear and the measuring gear at the same time, which the drive does not support.

1. Read the fault value in r0949 and determine the fault cause dd together with the affected encoder data set, component number and drive data set (see the fault value decoding below).
2. Fault cause 0: use an absolute encoder.
3. Fault cause 1: use a Control Unit with sufficient NVRAM — position tracking cannot be activated if the memory of the internal NVRAM is not sufficient or the Control Unit does not have an NVRAM.
4. Fault causes 2 and 4: if necessary, de-select the position tracking — via p0411 for the measuring gear and via p2720 for the load gear.
5. Fault cause 3: activate position tracking of the load gear in the same encoder data set only if the gear ratio (p2504, p2505), the axis type (p2720.1) and the tolerance window (p2722) are also the same. These parameters must be identical in all drive data sets that use the same motor encoder (p187).

• In the message value the drive shows the component number, the encoder data set, the drive data set and the fault cause.
• The fault value in r0949 is interpreted hexadecimal and has the structure ddccbbaa: aa = encoder data set, bb = component number, cc = drive data set, dd = fault cause.
• dd = 00 hex (0 dec): an absolute encoder is not being used.
• dd = 01 hex (1 dec): position tracking cannot be activated because the memory of the internal NVRAM is not sufficient or a Control Unit does not have an NVRAM.
• dd = 02 hex (2 dec): for a linear axis, the position tracking was activated for the load and measuring gear.
• dd = 03 hex (3 dec): position tracking cannot be activated because position tracking with another gear ratio, axis type or tolerance window has already been detected for this encoder data set.
• dd = 04 hex (4 dec): a linear encoder is being used.

• r0949 — fault value: read the fault value here and interpret it hexadecimal as ddccbbaa to obtain encoder data set, component number, drive data set and fault cause.
• p0404 — encoder configuration effective: shows the encoder configuration that is actually in effect, so you can verify the encoder setting the position tracking was activated with.
• p0411 — measuring gear configuration: de-select or activate position tracking for the measuring gear (fault causes 2 and 4).
• p2720 — load gear configuration: de-select or activate position tracking for the load gear (fault causes 2 and 4); bit 1 (p2720.1) holds the axis type that must match for fault cause 3.
• p2504 — LR motor/load motor distance: part of the load gear ratio that must be the same in the encoder data set for fault cause 3.
• p2505 — LR motor/load load revolutions: the second part of the load gear ratio that must be the same for fault cause 3.
• p2722 — load gear position tracking tolerance window: the tolerance window that must be the same when position tracking is activated for the load gear (fault cause 3).

The fault is acknowledged immediately after it occurs; switching the drive power on also acknowledges it. While the fault is active, the affected drive object is switched off, and the drive only restarts once the position tracking configuration has been corrected and the fault acknowledged. If the drive signals the same condition as an alarm instead, no acknowledgement is required.