Repair Small Burnt Sections in Voltage Regulator Coils

Repair of Partial Burnout in Voltage Regulator Coil

When a portion of the voltage regulator coil is burned out, it is usually unnecessary to completely dismantle and rewind the entire coil.

The repair method is as follows: remove the burned and damaged section of the coil, replace it with enameled wire of the same diameter, secure it firmly with epoxy resin, and then level it with a fine-tooth file. Polish the surface with No. 00 sandpaper and clean off any copper particles with a brush. Fill the recess left after removing the damaged wire with epoxy resin, then rewind the coil. Allow it to cure for 24 hours, and then smooth the surface with a file. The rewinding method is the same as previously described.

If the number of damaged turns is small—approximately less than 2% of the total coil turns—the damaged section can be bypassed. After removing the damaged turns, bridge the corresponding segment where the carbon brush slides with a flat piece or strip of oxygen-free copper (purple copper), ensuring good electrical continuity. Seal it firmly with epoxy resin and level it with a fine-tooth file (the purple copper piece or strip must remain exposed). The purpose of installing the purple copper piece or strip is to prevent power interruption when the carbon brush passes over the section where the coil has been removed.