Drive Overheating
Schneider Electric · Altivar 312 Variable Frequency Drive
¿Qué significa OHF ?
This fault indicates that the internal temperature of the drive has exceeded its safe operating threshold. Common causes include inadequate cooling due to blocked ventilation, a faulty cooling fan, high ambient temperatures, or sustained operation at current levels close to the drive's maximum rating. Persistent overheating can lead to premature failure of internal components.
Causas comunes
- Inadequate cooling due to blocked ventilation ducts or heavily dust-laden heatsink fins.
- Malfunctioning cooling fan, indicated by no rotation or unusual noise, reducing airflow through the drive.
- Ambient temperature within the control panel exceeding the drive's maximum specified operating limit (e.g., above 50°C).
- Excessive drive switching frequency (Parameter P7-14) for the current load and ambient conditions, leading to higher internal losses.
- Overcurrent or sustained high load operation stressing the drive's thermal capacity, especially if motor current (P2-01) is close to drive nominal.
Pasos de reparación & Lista de verificación
Haga clic en los pasos para seguir su progreso.
- 1
1. Measure the ambient temperature at the drive's air intake vents (must be within the drive's specified operating range, e.g., 0-50°C).
- 2
2. Inspect the drive's heatsink fins and ventilation openings for any accumulation of dust, debris, or foreign objects. Clean thoroughly with compressed air.
- 3
3. Verify the cooling fan operation by observing its rotation or measuring its supply voltage (e.g., 24VDC) at the fan terminals. Replace the fan unit if faulty.
- 4
4. Review Parameter P7-14 (Switching Frequency) and P7-15 (Boost Current). If set excessively high, reduce these values, monitoring motor performance.
- 5
5. Measure the current draw on the motor output terminals (U, V, W) using a clamp meter to confirm it does not exceed the drive's continuous output current rating.