What causes Okuma OSP alarm 2158?

Overload operation — excessive cutting load or rapid duty cycle on the indicated axis/spindle. Failed or blocked inverter unit cooling fan or heatsink. High cabinet ambient temperature or clogged air filters. Faulty inverter unit.

How do I fix Okuma OSP alarm 2158?

1. Note the axis name (or spindle) shown in the alarm object to identify which inverter unit is overheating. 2. Let the unit cool down, then review the recent machining: reduce cutting load, feed, or duty cycle on that axis/spindle if it has been running heavily overloaded. 3. Lock out main power and allow the drive to discharge before opening the electrical cabinet; then check the inverter unit cooling fan for operation and the heatsink and cabinet filters for dust blockage — clean or replace as needed. 4. Verify cabinet ambient temperature and airflow are within specification; restore any failed cabinet cooling. 5. If overheating recurs under normal load with cooling confirmed good, the inverter unit itself is suspect — record the alarm number and object and contact Okuma service.

Okuma OSP codes

axismd.ai

Okuma OSP Controller

Drive · Intermediate

Alarm 2158

Okuma OSP Alarm B 2158 - MCS Power unit overheat

The temperature inside the MCS inverter (power) unit rose abnormally high for the axis or spindle shown in the alarm object. This is typically caused by an overloaded drive or a cooling problem in the inverter unit, and continued operation risks damaging the power unit.

Okuma OSPDriveIntermediate

2158

Okuma OSP Alarm B 2158 - MCS Power unit overheat

MCS Power unit overheat

Common Causes

Overload operation — excessive cutting load or rapid duty cycle on the indicated axis/spindle
Failed or blocked inverter unit cooling fan or heatsink
High cabinet ambient temperature or clogged air filters
Faulty inverter unit

Troubleshooting Steps

1Note the axis name (or spindle) shown in the alarm object to identify which inverter unit is overheating.
2Let the unit cool down, then review the recent machining: reduce cutting load, feed, or duty cycle on that axis/spindle if it has been running heavily overloaded.
3Lock out main power and allow the drive to discharge before opening the electrical cabinet; then check the inverter unit cooling fan for operation and the heatsink and cabinet filters for dust blockage — clean or replace as needed.
4Verify cabinet ambient temperature and airflow are within specification; restore any failed cabinet cooling.
5If overheating recurs under normal load with cooling confirmed good, the inverter unit itself is suspect — record the alarm number and object and contact Okuma service.

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