F33806 — Encoder 3: Initialization error

F33806 reports that Encoder 3 was not successfully initialized. The initialization runs on the Sensor Module for Encoder 3: the drive matches the mid-voltages of the individual encoder tracks and, for an EnDat 2.2 measuring unit, initializes the unit and reads out and checks its data. If any of these steps fails, the drive raises F33806 and codes the failed step in the fault value. Depending on how the message is configured, the same condition can also be output only as an alarm (A) or with no reaction (N).

• The encoder was not successfully initialized; the precise reason is coded bit by bit in the fault value in r0949 (decoded below).
• Initialization with the motor rotating failed because the coarse and fine position deviated (bits 0, 1).
• Mid-voltage matching was unsuccessful for one of the tracks (bits 2 ... 9), or the measured mid-voltages deviate too much from one another (bits 10 ... 15).
• Internal errors in the evaluation electronics (bits 16 ... 20).
• The EnDat 2.2 measuring unit could not be initialized, or its data is faulty (bits 28 ... 31).

1. Acknowledge the fault first — if it can be acknowledged and does not return, the initialization succeeded on the next attempt.
2. If the fault comes back, read the fault value in r0949 and note which bits are set.
3. Bits 2 ... 9 set: check the encoder power supply.
4. Bits 2 ... 14 set: check the cable belonging to the faulty track.
5. Only bit 15 set: check track R and check the settings in p0404.
6. Bit 28 set: check the cable between the EnDat 2.2 converter and the measuring unit.
7. Bits 29 ... 31 set: replace the defective measuring unit.

The message value %1 is the fault value; the drive stores it in r0949. Interpret it bit by bit using the following list:

• Bits 0, 1: encoder initialization with the motor rotating has failed (deviation involving coarse and fine position in encoder pulses/4)
• Bit 2: mid-voltage matching for track A unsuccessful
• Bit 3: mid-voltage matching for track B unsuccessful
• Bit 4: mid-voltage matching for acceleration input unsuccessful
• Bit 5: mid-voltage matching for track safety A unsuccessful
• Bit 6: mid-voltage matching for track safety B unsuccessful
• Bit 7: mid-voltage matching for track C unsuccessful
• Bit 8: mid-voltage matching for track D unsuccessful
• Bit 9: mid-voltage matching for track R unsuccessful
• Bit 10: the difference in mid-voltages between A and B is too great (> 0.5 V)
• Bit 11: the difference in mid-voltages between C and D is too great (> 0.5 V)
• Bit 12: the difference in mid-voltages between safety A and safety B is too great (> 0.5 V)
• Bit 13: the difference in mid-voltages between A and safety B is too great (> 0.5 V)
• Bit 14: the difference in mid-voltages between B and safety A is too great (> 0.5 V)
• Bit 15: the standard deviation of the calculated mid-voltages is too great (> 0.3 V)
• Bit 16: internal fault — fault when reading a register (CAFE)
• Bit 17: internal fault — fault when writing a register (CAFE)
• Bit 18: internal fault: no mid-voltage matching available
• Bit 19: internal error — ADC access error
• Bit 20: internal error — no zero crossover found
• Bit 28: error while initializing the EnDat 2.2 measuring unit
• Bit 29: error when reading out the data from the EnDat 2.2 measuring unit
• Bit 30: EEPROM checksum of the EnDat 2.2 measuring unit incorrect
• Bit 31: data of the EnDat 2.2 measuring unit inconsistent

Bits 0, 1 apply up to hardware 6SL3055-0AA00-5*A0; bits 2 ... 20 apply from hardware 6SL3055-0AA00-5*A1 and higher.

• r0949 — read the fault value here to see which initialization step of Encoder 3 failed.
• p0404 — check the effective encoder configuration here when bit 15 is the only bit set.

Acknowledge the fault — for many occurrences the initialization then succeeds on the next attempt and the fault stays cleared. Acknowledgement is only possible while the pulses are inhibited, so bring the drive into the pulse-inhibit state, acknowledge the fault at the operator panel or in the commissioning tool, and restart. If the fault cannot be acknowledged or returns immediately, work through the checks above. Where the same condition is configured as an alarm (A) or with no reaction (N), there is neither an automatic reaction nor an acknowledgement.