What causes Okuma OSP alarm 4170?

Magnetic encoder or its wiring faulty, or large gap between magnetic encoder and gear. Mismatch between the number of gear teeth of the magnetic encoder and the servo data file data. A-phase or B-phase voltage abnormal, or magnetic encoder data error.

How do I fix Okuma OSP alarm 4170?

1. Read the code number shown with the alarm: code XXXX=A = A-phase voltage abnormal; YYYY shows the A-phase voltage; code XXXX=B = B-phase voltage abnormal; YYYY shows the B-phase voltage; code XXXX=C = Magnetic encoder data error; YYYY is 0 fixed; code XXXX=other = Servo data file set value (PG gear teeth x 4 - 1) at count-over error; YYYY shows detected count value 2. Read the code: XXXX=A means A-phase voltage abnormal, B means B-phase voltage abnormal, C means magnetic encoder data error; other XXXX values are the servo data file set value (number of PG gear teeth x 4 - 1) detected at a count-over error. YYYY shows the A or B phase voltage, or the detected count value. 3. Lock out power and inspect the magnetic encoder mounting: the gap between the magnetic encoder and its gear must be within spec; adjust if it has shifted. 4. Check the magnetic encoder wiring and connector for damage or looseness. 5. Verify the number of gear teeth of the magnetic encoder matches the servo data file data; correct the data file if the gear was changed. 6. If the gap, wiring, and data file are correct, replace the magnetic encoder.

Okuma OSP codes

axismd.ai

Okuma OSP Controller

Servo/Axis · Intermediate

Alarm 4170

Okuma OSP Alarm D 4170 - MCS Magnetic encoder alarm

The magnetic pulse generator lost the ability to detect motor speed, or the gear tooth count on the magnetic encoder disagrees with what the MCS data file expects, for the axis or spindle named in the object field.

Okuma OSPServo/AxisIntermediate

4170

Okuma OSP Alarm D 4170 - MCS Magnetic encoder alarm

MCS Magnetic encoder alarm

Common Causes

Magnetic encoder or its wiring faulty, or large gap between magnetic encoder and gear
Mismatch between the number of gear teeth of the magnetic encoder and the servo data file data
A-phase or B-phase voltage abnormal, or magnetic encoder data error

Troubleshooting Steps

1Read the code number shown with the alarm: code XXXX=A = A-phase voltage abnormal; YYYY shows the A-phase voltage; code XXXX=B = B-phase voltage abnormal; YYYY shows the B-phase voltage; code XXXX=C = Magnetic encoder data error; YYYY is 0 fixed; code XXXX=other = Servo data file set value (PG gear teeth x 4 - 1) at count-over error; YYYY shows detected count value
2Read the code: XXXX=A means A-phase voltage abnormal, B means B-phase voltage abnormal, C means magnetic encoder data error; other XXXX values are the servo data file set value (number of PG gear teeth x 4 - 1) detected at a count-over error. YYYY shows the A or B phase voltage, or the detected count value.
3Lock out power and inspect the magnetic encoder mounting: the gap between the magnetic encoder and its gear must be within spec; adjust if it has shifted.
4Check the magnetic encoder wiring and connector for damage or looseness.
5Verify the number of gear teeth of the magnetic encoder matches the servo data file data; correct the data file if the gear was changed.
6If the gap, wiring, and data file are correct, replace the magnetic encoder.

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