High Neutral Currents

High neutral currents can be caused by unbalanced and/or non-linear loads with high harmonics. K-rated transformers have a 200% rated neutral. Amperage should be measured with a meter capable of measuring true RMS currents.

Check: Solution:
Check the load to make sure it is balanced. Any load unbalance results in neutral currents. Improve the load balance between the three phases. General purpose transformers have a 125% rated neutral.
Check the load to determine if it has high amounts of harmonics from single phase sources. For non-linear loads, use k-rated tranformers with 200% rated neutrals. Select a k-rated transformer with a k-factor suitable for the specific level of harmonics.
Check to make sure all three legs of the transformer or transformer bank are operating. Check coil continuity and blown fuses or tripped breakers. If a fuse is blown, clear the source of the fault and replace the fuse. If a breaker has tripped, clear the fault, check the settings and turn on the breaker.  If the transformer coil is damaged, the transformer will have to be repaired or replaced.  Please contact HPS Customer Service.