Siemens SINAMICS S Series - F31117 (N, A) Encoder 1: Inversion error signals A and B and R; F31118 (N, A) Encoder 1: Speed difference outside the tolerance range; F31120 (N, A) Encoder 1: Power supply voltage

List of faults and alarms
Faults and Alarms
3-1643
© Siemens AG 2007 All Rights Reserved
SINAMICS S List Manual (LH1), 07/2007
F31117 (N, A) Encoder 1: Inversion error signals A and B and R
Drive object: All objects
Reaction: A_INFEED: NONE
SERVO: ENCODER (IASC / DCBRAKE, NONE)
VECTOR: ENCODER (IASC / DCBRAKE, NONE)
Acknowledge: IMMEDIATELY
Cause: For a square-wave signal encoder (TTL. bipolar. double ended) the A* and B* and R* signals are not inverted with
respect to signals A and B and R.
See also: p0491 (Motor encoder fault response ENCODER)
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?
Reaction upon N: NONE
Acknowl. upon N: NONE
Reaction upon A: NONE
Acknowl. upon A: NONE
F31118 (N, A) Encoder 1: Speed difference outside the tolerance range
Drive object: All objects
Reaction: A_INFEED: NONE
SERVO: ENCODER (IASC / DCBRAKE, NONE)
VECTOR: ENCODER (IASC / DCBRAKE, NONE)
Acknowledge: PULSE INHIBIT
Cause: For an HTL/TTL encoder, the speed difference has exceeded the value in p0492 over several sampling cycles.
Encoder 1 is used as motor encoder and can be effective has fault response to change over to sensorless operation.
Fault value (r0949, interpret decimal):
Only for internal Siemens troubleshooting.
See also: p0491 (Motor encoder fault response ENCODER)
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).
Reaction upon N: NONE
Acknowl. upon N: NONE
Reaction upon A: NONE
Acknowl. upon A: NONE
F31120 (N, A) Encoder 1: Power supply voltage
Drive object: All objects
Reaction: A_INFEED: NONE
SERVO: ENCODER (IASC / DCBRAKE, NONE)
VECTOR: ENCODER (IASC / DCBRAKE, NONE)
Acknowledge: PULSE INHIBIT
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, interpret binary):
Bit 0: Undervoltage condition on the sense line (threshold 4.75 V).
Bit 1: Encoder power supply voltage overcurrent condition (threshold 450 mA).
See also: p0491 (Motor encoder fault response ENCODER)
Remedy: For fault value, bit 0 = 1:
- correct encoder cable connected?
- check the plug connections of the encoder cable.
- SMC30: Check the parameterization (p0404.22).
For fault value, bit 1 = 1:
- correct encoder cable connected?
- replace the encoder or encoder cable.