E.OS fault in KEB COMBIVERT F5 Drive indicates an Overspeed. This means the motor’s speed exceeded the internal safety limit, potentially due to bad machine data parameters or a loss of load control.
Cause:
The inverter internal overspeed is dictated as 125% of the LF.20 Contract Speed. This level is fixed and cannot be adjusted.
Possible causes of an overspeed error include:
- Incorrect setting of the Machine Data parameters LF.20-25: The Machine Data parameters are used as a scalar to convert a linear speed (e.g. ft/min) to a rotary speed (rpm) used by the inverter. If the machine data is not set correctly, the overspeed limit may be calculated too low when control modes which dictate the drive speed exceed this limit.
- Lack of control: Maximum Torque limit or peak inverter current reached. 0.LF.36 Maximum Torque may be set too low (default = 150%; typical for high speed/full load operation = 200-250%).
- Excessive current: Incorrect motor data, specifically the motor rated speed and frequency relationship for PM Synchronous Motors, or incorrect Encoder Pole Position (LF.77).
- Speed gains set too high or low: For an unloaded PM Synchronous Motor, the default speed gains LF.31-33 may be too high, causing the machine to jerk quickly. If left too low for normal operation, the drive may not track the speed.
- Modulation gain exceeds maximum: If the modulation grade in ru42. exceeds 100%, there may be a loss of speed control.
- Sudden, excessive movement: Incorrect motor data or incorrect Encoder Pole Position for PM Synchronous Motors.
Remedy:
- Check and verify Machine Data parameters LF.20-25.
- Monitor the motor current to see if it reaches a current corresponding to the 0.LF.36 Maximum Torque or the drive Peak Current rating. Adjust 0.LF.36 if set too low.
- Verify motor data, specifically the motor rated speed and frequency relationship for PM Synchronous Motors (see Section 5.6).
- Verify and correct Encoder Pole Position (LF.77) for PM Synchronous Motors. Relearn Encoder Pole Position as needed (see Section 5.11).
- Verify speed gains are appropriately configured. Adjust LF.31-33 if needed.
- Ensure that the modulation grade in ru42. does not exceed 100%.
