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Okuma OSP Controller
Servo/Axis · Intermediate
Okuma OSP Alarm D 4686 - MCS Rotary encoder 4 error
The MCS drive detected illegal data from rotary encoder 4, a HEIDENHAIN encoder, on the axis named in the object. The encoder's position data cannot be trusted, so the axis is stopped.
4686
Okuma OSP Alarm D 4686 - MCS Rotary encoder 4 error
MCS Rotary encoder 4 error
The MCS drive detected illegal data from rotary encoder 4, a HEIDENHAIN encoder, on the axis named in the object. The encoder's position data cannot be trusted, so the axis is stopped.
Common Causes
- Failed HEIDENHAIN rotary encoder 4 (internal electronics failure)
- Encoder cable or connector fault corrupting the data
- Contamination at the encoder read head or graduated drum
- Electrical noise on the encoder signal line
Troubleshooting Steps
- 1Note the axis from the alarm object and inspect the cable and connector of the HEIDENHAIN rotary encoder 4 for damage, oil or loose pins; reseat both ends.
- 2Check the encoder environment for coolant or chip contamination at the read head and clean carefully if found.
- 3Swap the encoder cable with a known-good cable to eliminate a wiring fault.
- 4Check encoder cable routing for noise exposure and keep it separated from motor power cables with the shield grounded.
- 5If the error persists with good cabling, replace rotary encoder 4 (HEIDENHAIN) as the manual's corrective action directs, then re-home the axis.
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