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E54 Feedback Loss Fault - 5 Green Flash 1 Yellow

With the Auto-Feedback Detection mode of the command SFB1, Aries firmware automatically checks for smart encoders (Q-encoders) before other feedback types on power-up or reset. If a Q-encoder is detected, the downloaded configuration on the drive would also be erased, in preparation for the drive configuration to be sent from the smart encoder. This could occur if the halls are incorrectly wired, or not detected due to noise.

Fixing the source of the noise problem can address this issue. The motor cable should be a braided-shielded cable grounded at the drive with the P-clip making a 360degree bond and at the motor case. The P-clip provides a much better RF ground any sort of drain wire as it provides a high-surface area and hence a lower impedance to ground. A motor's ground wire in with the motor phases (typically green with yellow stripe) is a protective earth ground and not a reliable RF ground. The cable should be making full connection to the P-clip completely around the cable; copper tape can help. A ferrite core (or ferrite bead) placed on the motor cable close to the drive will also act as a low-pass filter on certain high-frequency transient voltages and can help as well. For full CE installation guidelines, see the Aries User's Guide.

If the fault is occurring on powerup or reset:
Remedy: Changing the SFB from 1 (auto-detect) to the set value (2 for standard encoder or 3 resolver, 5 for Smart Encoder, 6 for absolute encoder) can sometimes fix this fault.If this fault only occurs after enabling the drive and commanding motion:
If a certain voltage (ENCFV) is commanded for a certain amount of time (ENCFT) and there is no encoder movement, the drive will fault will the encoder loss fault. Default for ENCFV is 7V, range is 0-10V. Default for ENCFT is 1000ms, range is 0-10000ms.
Remedy: Changing the ENCFT from 1000 to 0 will turn this off.

If this fault only occurs after enabling the drive, the LEDs flicker red & green before faulting with 1 yellow and 5 flashing greens:
Cause: Drive has faulted with Encoder Loss during auto-commutation if no encoder is detected (signified by both encoder phases being close to 0 volts) or during the final auto-commutation move.
Remedy: Check encoder wiring and connections.