G
I have been battling to understand why lightning took out distribution transformers in a company I did internship in.
A 100KVA distribution transformer failed when lightning occurred despite the fact that we had on the average 250M ohms winding insulation resistance on all 3 phases and earth resistance values obtained at commissioning was less than 5 ohms. the arresters rated 36kV were located closed to the transformer (34.5kV system voltage) and drop out fuses rated 2A. What could we have done differently?
A 100KVA distribution transformer failed when lightning occurred despite the fact that we had on the average 250M ohms winding insulation resistance on all 3 phases and earth resistance values obtained at commissioning was less than 5 ohms. the arresters rated 36kV were located closed to the transformer (34.5kV system voltage) and drop out fuses rated 2A. What could we have done differently?
