Resolver error at X7

What does Sd2 mean?

The resolver cable connected to X7 is interrupted, or the resolver itself is faulty. This prevents accurate motor position feedback, which is crucial for precise motor control.

• Open circuit or high resistance in the resolver excitation winding cable (e.g., X7/1 to X7/2), preventing excitation signal.
• Open circuit or short circuit in the resolver sine/cosine feedback windings cable (e.g., X7/3 to X7/4, X7/5 to X7/6), leading to no position signal.
• Damaged resolver sensor within the motor itself, often due to mechanical shock, overheating, or ingress of contaminants.
• Incorrect shielding or grounding of the resolver cable, leading to noise interference on the low-level sine/cosine signals.
• Loose or corroded connections at the X7 terminal block on the controller or at the resolver motor connector.

Click steps to track your progress.

1. 1

   Power off the drive, disconnect the resolver cable from X7, and measure resistance across X7/1-X7/2 (excitation) and X7/3-X7/4, X7/5-X7/6 (feedback) for open circuits.

2. 2

   Using a multimeter, check for continuity of each individual wire in the resolver cable from end to end (connector to X7 terminals).

3. 3

   Inspect the resolver cable for cuts, kinks, or signs of crushing; replace the cable if physical damage is evident.

4. 4

   Verify the integrity of the cable shield connection at both the motor and the X7 connector on the controller.

5. 5

   With power on, use an oscilloscope to check for the presence and amplitude of the excitation signal on X7/1 and X7/2 terminals (typically 5-10V AC).

6. 6

   If possible, swap the resolver with a known good one (if available) to confirm if the resolver sensor or the drive input is at fault.