Siemens SINAMICS G List Manual page 603

Remedy: - check that the encoder cables are routed in compliance with EMC.
- check the plug connections.
- replace the encoder or encoder cable.
- check the encoder module (e.g. contacts).
Acknowledgment:
This fault can only be acknowledged by canceling the pulses.
F31116 Encoder 1: Amplitude error, monitoring track A + B
Reaction: ENCODER (DCBRAKE, NONE)
Acknowledge: IMMEDIATELY
Cause: The amplitude of the rectified encoder signals A and B is not within the tolerance bandwidth (hardware monitoring).
The nominal signal level of the encoder must lie in the range 375 mV to 600 mV (500 mV -25 % / +20 %).
On the other hand, the hardware response thresholds are at < 176 mV and > 1.35 V.
Fault value (r0949, decimal):
Low word: Signal level, track A (16 bits with sign).
High word: Signal level, track B (16 bits with sign).
A signal level of 500 mV corresponds to the numerical value 5333 hex = 21299 dec.
These analog values are not measured at the same time with the hardware fault output.
Remedy: - check that the encoder cables are routed in compliance with EMC.
- check the plug connections.
- replace the encoder or encoder cable.
- check the encoder module (e.g. contacts).
F31117 Encoder 1: Inversion error, signals A and B
Reaction: ENCODER (DCBRAKE, NONE)
Acknowledge: IMMEDIATELY
Cause: For a square-wave signal encoder (TTL. bipolar. double ended) the A* and B* signals are not inverted with respect
to signals A and B.
Remedy: Check the setting of p0405: p0405.2 = 1 is only possible if the encoder is connected at X520.
Check the encoder/cable: Does the encoder supply TTL signals and the associated inverted signals?
F31118 Encoder 1: Speed difference outside the tolerance range
Reaction: ENCODER (DCBRAKE, NONE)
Acknowledge: READY
Cause: The speed difference between two sampling cycles has exceeded the value in p0492.
The error is only evaluated for HTL/TTL encoders.
Encoder 1 is used as motor encoder and can be effective has fault response to change over to sensorless operation.
Fault value (r0949, decimal):
Speed difference per current controller clock cycle in increments.
Remedy: - check the tachometer feeder cable for interruptions.
- check the grounding of the tachometer shielding.
- if required, increase the maximum speed difference per sampling cycle (p0492).
Acknowledgment:
This fault can only be acknowledged by canceling the pulses.
F31120 Encoder 1: Power supply volt.
Reaction: ENCODER (DCBRAKE, NONE)
Acknowledge: READY
Cause: Encoder power supply voltage fault.
Note:
If the encoder cables 6FX2002-2EQ00-.... and 6FX2002-2CH00-.... are interchanged, this can result in the encoder
being destroyed because the pins of the operating voltage are reversed.
Fault value (r0949, binary):
Bit 0: Undervoltage condition on the sense line (threshold 4.75 V).
Bit 1: Encoder power supply voltage overcurrent condition (threshold 450 mA).
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SINAMICS G List Manual, Edition 12.2004
Faults and Alarms
List of faults and alarms
3-603