What causes Okuma OSP alarm 4149?

Internal cooling fan failed or seized. Fan blocked by dust, chips, or debris. Fan power connector loose or unplugged inside the power supply. Fan power feed from the supply not present.

How do I fix Okuma OSP alarm 4149?

1. Read the code number shown with the alarm: code 1 = Fixed code: the MCS power supply unit internal cooling fan is detected stopped. 2. Read the code: it is fixed as 1 for this alarm, and note whether the object shows an axis name or none/spindle to identify which MCS power supply is complaining. 3. Do not keep cycling power to 'see if it clears'; shut down, lock out incoming power, and wait for the drive DC bus to discharge before opening the cabinet or power supply area. 4. With power safely off, inspect the power supply's internal fan for free rotation by hand and remove packed dust/chips or any object jamming the blades. 5. Check the fan power connector for being fully seated and for burned or backed-out terminals; a loose fan connector is a cheaper fix than a power supply. 6. Restore power only after the area is closed and safe, then confirm the fan starts immediately; replace the fan if it remains stopped or noisy/slow. 7. If the fan and connector are good but the supply still reports fan stop, record alarm D 4149, Code 1, and the object and contact Okuma service.

Okuma OSP codes

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Okuma OSP Controller

Power Supply · Intermediate

Alarm 4149

Okuma OSP Alarm D 4149 - MCS Power supply unit internal cooling fan stop

The MCS power supply unit has detected that its internal cooling fan is stopped; the code is fixed at 1. Continued running risks overheating the power supply, so treat this as a cooling/hardware fault rather than a program issue.

Okuma OSPPower SupplyIntermediate

4149

Okuma OSP Alarm D 4149 - MCS Power supply unit internal cooling fan stop

MCS Power supply unit internal cooling fan stop

Common Causes

Internal cooling fan failed or seized
Fan blocked by dust, chips, or debris
Fan power connector loose or unplugged inside the power supply
Fan power feed from the supply not present

Troubleshooting Steps

1Read the code number shown with the alarm: code 1 = Fixed code: the MCS power supply unit internal cooling fan is detected stopped.
2Read the code: it is fixed as 1 for this alarm, and note whether the object shows an axis name or none/spindle to identify which MCS power supply is complaining.
3Do not keep cycling power to 'see if it clears'; shut down, lock out incoming power, and wait for the drive DC bus to discharge before opening the cabinet or power supply area.
4With power safely off, inspect the power supply's internal fan for free rotation by hand and remove packed dust/chips or any object jamming the blades.
5Check the fan power connector for being fully seated and for burned or backed-out terminals; a loose fan connector is a cheaper fix than a power supply.
6Restore power only after the area is closed and safe, then confirm the fan starts immediately; replace the fan if it remains stopped or noisy/slow.
7If the fan and connector are good but the supply still reports fan stop, record alarm D 4149, Code 1, and the object and contact Okuma service.

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