What causes Okuma OSP alarm 0791?

Failed Rotary encoder 1. A/B phase signal amplitude too large or too small inside the encoder. AD offset voltage drift on the A or B phase. Internal encoder CPU fault (alarm code 80-FF).

How do I fix Okuma OSP alarm 0791?

1. Read the code number shown with the alarm: code XX bit7 = Encoder alarm present; code XX bit6 = Encoder communication error; code XX=8X = Output amplitude normal; code XX=9X = Output amplitude small; code XX=AX = Output amplitude large; code XX=BX = Output amplitude too small; code YY=00 = Not started; code YY=01 = Stopped by stop command 2. Read the code on screen: XX is the encoder status (bit7 alarm, bit6 communication error; 8X amplitude normal, 9X amplitude small, AX amplitude large, BX amplitude too small), YY is the encoder's own alarm code, ZZZZ is the position data per pitch. 3. Branch on YY: 02 illegal control parameter, 0E synchronization error, 0F illegal excitation output, 11-17 AD offset voltage decrease/rise on A and/or B phase, 25-2F signal amplitude excessive or too small, 80-FF internal CPU fault. 4. Note the axis in the alarm object, lock out power, and let the drive discharge before handling connectors. 5. Inspect the Rotary encoder 1 cable and connector for damage, coolant, or loose contact; reseat and retest. 6. If the same status/alarm code returns, replace Rotary encoder 1 as the manual directs. 7. If the fault persists after replacement, record the alarm number, full code, and axis and contact Okuma service.

Okuma OSP codes

axismd.ai

Okuma OSP Controller

Servo/Axis · Intermediate

Alarm 0791

Okuma OSP Alarm P 0791 - MCS Rotary encoder 1 error

The MCS drive detected illegal data from Rotary encoder 1 on the indicated axis. The on-screen code gives the encoder status, an internal alarm code (such as offset voltage or signal amplitude faults on the A/B phases), and the position data at the time of failure.

Okuma OSPServo/AxisIntermediate

0791

Okuma OSP Alarm P 0791 - MCS Rotary encoder 1 error

MCS Rotary encoder 1 error

Common Causes

Failed Rotary encoder 1
A/B phase signal amplitude too large or too small inside the encoder
AD offset voltage drift on the A or B phase
Internal encoder CPU fault (alarm code 80-FF)

Troubleshooting Steps

1Read the code number shown with the alarm: code XX bit7 = Encoder alarm present; code XX bit6 = Encoder communication error; code XX=8X = Output amplitude normal; code XX=9X = Output amplitude small; code XX=AX = Output amplitude large; code XX=BX = Output amplitude too small; code YY=00 = Not started; code YY=01 = Stopped by stop command
2Read the code on screen: XX is the encoder status (bit7 alarm, bit6 communication error; 8X amplitude normal, 9X amplitude small, AX amplitude large, BX amplitude too small), YY is the encoder's own alarm code, ZZZZ is the position data per pitch.
3Branch on YY: 02 illegal control parameter, 0E synchronization error, 0F illegal excitation output, 11-17 AD offset voltage decrease/rise on A and/or B phase, 25-2F signal amplitude excessive or too small, 80-FF internal CPU fault.
4Note the axis in the alarm object, lock out power, and let the drive discharge before handling connectors.
5Inspect the Rotary encoder 1 cable and connector for damage, coolant, or loose contact; reseat and retest.
6If the same status/alarm code returns, replace Rotary encoder 1 as the manual directs.
7If the fault persists after replacement, record the alarm number, full code, and axis and contact Okuma service.

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