A31410 — Encoder 1: Communication error (encoder and Sensor Module)

A31410 reports a serial communication protocol transfer error between Encoder 1 and the evaluation module that reads the encoder — the encoder's data can no longer be transferred correctly. The manuals print this code under two titles, Encoder 1: Communication error (encoder and Sensor Module) and Encoder 1: Serial communications, and describe the identical condition. The drive can also raise the same condition as a fault or as a message without reaction, depending on its configuration. Which transfer problem occurred is coded bit by bit in the alarm value r2124.

• Serial communication protocol transfer error between the encoder and the evaluation module.

1. Check that the encoder cables are routed in compliance with EMC.
2. Check the plug connections.
3. Replace the encoder.

The drive outputs the cause of this message as a binary value (Fault cause: %1 bin); the same alarm value can be read in r2124, interpreted in binary. The bits have the following meaning:

• Bit 0: alarm bit in the position protocol.
• Bit 1: incorrect quiescent level on the data line.
• Bit 2: encoder does not respond (does not supply a start bit within 50 ms).
• Bit 3: CRC error: the checksum in the protocol from the encoder does not match the data.
• Bit 4: encoder acknowledgment error: the encoder incorrectly understood the task (request) or cannot execute it.
• Bit 5: internal error in the serial driver: an illegal mode command was requested.
• Bit 6: timeout when cyclically reading.
• Bit 8: protocol is too long (e.g. > 64 bits).
• Bit 9: receive buffer overflow.
• Bit 10: frame error when reading twice.
• Bit 11: parity error.
• Bit 12: data line signal level error during the monoflop time.

• r2124 — alarm value: read it in binary to see which of the bits listed above the drive has set for this Encoder 1 message.

As an alarm, this message requires no acknowledgement and the drive takes no automatic action. If the drive is configured to issue the same condition as a fault instead, that fault must be acknowledged IMMEDIATELY before the drive can be restarted.