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Okuma OSP Controller
Servo/Axis · Intermediate
Okuma OSP Alarm C 3750 - Tailstock absolute encoder error
The [Unit faulty/] signal from the tailstock absolute encoder stayed OFF longer than 1 second, or the NC was powered on while that signal was OFF. The tailstock position cannot be trusted until the encoder reports healthy again.
3750
Okuma OSP Alarm C 3750 - Tailstock absolute encoder error
Tailstock absolute encoder error
The [Unit faulty/] signal from the tailstock absolute encoder stayed OFF longer than 1 second, or the NC was powered on while that signal was OFF. The tailstock position cannot be trusted until the encoder reports healthy again.
Common Causes
- Tailstock absolute encoder unit powered down or missing its power supply
- Encoder not in RUN mode (wrong operating mode selected on the unit)
- Internal encoder unit alarm such as sensor or memory error
- Cable or connector fault on the [Unit faulty/] signal line
Troubleshooting Steps
- 1Check that the tailstock absolute encoder unit is powered: verify its power supply is ON and the unit's power indicator is lit.
- 2Confirm the operating mode selected on the encoder unit is RUN mode; a unit left in a setup or standby mode will hold the [Unit faulty/] signal OFF.
- 3Look at the encoder unit's own alarm display for an internal sensor error or memory error and address that unit-level fault per the tailstock encoder unit documentation.
- 4Inspect the cable and connector carrying the [Unit faulty/] signal from the encoder to the NC input for damage or looseness.
- 5Once the unit shows healthy and RUN mode is selected, cycle the NC power and confirm the tailstock absolute position reads correctly.
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