What causes Okuma OSP alarm 4764?

The spindle has not been rotated more than 360 degrees since power-on, so the encoder marker pulse was never read. The spindle encoder is faulty and is not producing the marker signal even when the spindle rotates. Encoder coupling or wiring fault preventing the marker pulse from reaching the control.

How do I fix Okuma OSP alarm 4764?

1. Read the code number shown with the alarm: code 1 = For push-button spindle orientation, the spindle encoder has not read its marker (reference) signal since power-on, so no orientation reference exists 2. Read the code shown with the alarm. Code 1 means the spindle encoder marker signal has not been detected since power-on. 3. Rotate the spindle through more than one full revolution (over 360 degrees), for example by running it at low speed in MDI, then retry the orientation push button. 4. If orientation still fails after a full rotation, inspect the spindle encoder coupling and connector for looseness or damage that could drop the marker pulse. 5. If the wiring and coupling are sound, replace the spindle encoder as directed by the manual. 6. If the alarm persists with a new encoder, record the alarm number and code and contact Okuma service.

Okuma OSP codes

axismd.ai

Okuma OSP Controller

Spindle · Intermediate

Alarm 4764

Okuma OSP Alarm D 4764 - Spindle orientation interlock

A spindle orientation was requested (via the orientation push button) but a required precondition was not met, so the control blocked the orientation cycle. With Code 1, the spindle encoder has not yet seen its marker (one-rotation reference) signal since power-on, so the control has no angular reference to orient against.

Okuma OSPSpindleIntermediate

4764

Okuma OSP Alarm D 4764 - Spindle orientation interlock

Spindle orientation interlock

Common Causes

The spindle has not been rotated more than 360 degrees since power-on, so the encoder marker pulse was never read
The spindle encoder is faulty and is not producing the marker signal even when the spindle rotates
Encoder coupling or wiring fault preventing the marker pulse from reaching the control

Troubleshooting Steps

1Read the code number shown with the alarm: code 1 = For push-button spindle orientation, the spindle encoder has not read its marker (reference) signal since power-on, so no orientation reference exists
2Read the code shown with the alarm. Code 1 means the spindle encoder marker signal has not been detected since power-on.
3Rotate the spindle through more than one full revolution (over 360 degrees), for example by running it at low speed in MDI, then retry the orientation push button.
4If orientation still fails after a full rotation, inspect the spindle encoder coupling and connector for looseness or damage that could drop the marker pulse.
5If the wiring and coupling are sound, replace the spindle encoder as directed by the manual.
6If the alarm persists with a new encoder, record the alarm number and code and contact Okuma service.

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