admin
An overload fault during production is one of the most frustrating problems on a servo press line.
## Distinguish Mechanical from Electrical Overload
Drive overload OL1/OL2: motor current exceeded the drive thermal model limit. Mechanical overload: load cell detected excessive force. Torque limit: drive instantaneous torque limit was hit.
## Mechanical Overload: Check the Die First
1. Check die alignment: a misaligned die can double the required forming force
2. Check material thickness: a 10% thickness increase means roughly 10% more forming force
3. Check lubrication: dry forming can increase force by 20-30%
4. Check for slug buildup in the die
5. Review tonnage trend: increasing frequency means the die is wearing
## Drive Overload: Check the Motion Profile
1. Check SPM vs rated SPM: running above rated continuous SPM triggers thermal overload
2. Check forming speed: too high increases peak current demand
3. Check ambient temperature: above 40C reduces continuous capacity by 15-20%
4. Check motor cooling: blocked fins or failed fan causes thermal overload
## Intermittent Overloads
Enable drive data logging and capture current waveform for 1000 strokes. Look for strokes where peak current is significantly higher than average. Correlate with coil position, time of day, or specific die stations. The answer is almost always in the data.