If you've got high voltage, and need high current
We have the solution


Rapidly growing energy demand and an aging assets is a reality, and unplanned disconnections are challenging industries around the world. Maintenance and monitoring of the assets is the key to gain maximum uptime. NTS offers a full range transformer services both onsite and in our workshop. NTS provides services throughout the transformer life cycle, from commissioning to recycling, for all brands and kinds of transformers. Our portfolio contain technical information for many of our service projects.


Maintenance onsite:

  • -Gasket replacement
  • -Replacement of protective relays
  • -Complete oil treatment
  • -Diverter switch revision
    • MR, all models
    • ASEA/ABB, all models
    • NI (san), all models
  • -DGA oil sampling 
  • -Overall cleaning
  • -Onsite diagnostic measurements
    • Ratio, windings resistance, Tan/Delta, FRA, Insulation test megger


Maintenance workshop:

  • - Full gasket replacement
  • - Full rewinding of types of windings
  • - Upgrade of core
  • - Replacement of all protective relays
  • - Complete oil treatment
  • - Complete tap changer overhaul
    •     MR, all models
    •     ASEA/ABB, all models
    •     NI (san), all models
  • - DGA, DP-value, Furan analysis  
  • - Overall cleaning
  • - Complete testing (IEC, ANSI/IEEE) 


National Industri tap changer overhaul, with new main contacts on a rectifier transformer from 1972.


Excerpts from service portfolio

National Industri EAF transformer, disassembled and new shell-type winding's assembled.  

Asea P K hydra plant transformer, disassembled and controlled after the transformer vault was flooded. 

Dry rectifier transformer with high voltage winding's short circuited. All winding's was replaced. 

Any questions about transformer service? Contact us and we will gladly assist you.