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Okuma OSP Controller
Servo/Axis · Intermediate
Okuma OSP Alarm B 2687 - MCS Rotary encoder 3 initialization failure
During power-up the MCS drive failed to complete initialization of rotary encoder 3, a HEIDENHAIN encoder, on the axis shown in the alarm object. Because the encoder did not initialize, the axis has no valid position feedback.
2687
Okuma OSP Alarm B 2687 - MCS Rotary encoder 3 initialization failure
MCS Rotary encoder 3 initialization failure
During power-up the MCS drive failed to complete initialization of rotary encoder 3, a HEIDENHAIN encoder, on the axis shown in the alarm object. Because the encoder did not initialize, the axis has no valid position feedback.
Common Causes
- Failed HEIDENHAIN rotary encoder 3
- Encoder cable or connector fault preventing initialization handshake
- Encoder power supply problem from the inverter unit
- Contamination or damage at the encoder read head
Troubleshooting Steps
- 1Identify the axis from the alarm object, then inspect the HEIDENHAIN rotary encoder 3 cable and connector for bent pins, oil ingress or damage and reseat both ends.
- 2Cycle power and watch whether the encoder initializes; a persistent failure on the same axis points to the encoder or its dedicated cable rather than a transient glitch.
- 3Check the encoder supply voltage at the encoder connector against the HEIDENHAIN specification for that encoder to rule out a power feed problem from the drive.
- 4If wiring and supply are good, replace rotary encoder 3 (HEIDENHAIN) with the specified unit per the manual's corrective action, then re-initialize and home the axis.
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