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Fuse coordination is a critical step in properly sizing and selecting protective devices for your transformer designs. H-J has long provided this service for our customers via an offline service, and the algorithms have been refined over the past decades. We are proud to deliver this service to customers with an online tool which allows user real-time feedback and information which you need in this fast-paced environment! H-J has developed one of the most extensive lines of fuses and product offerings in the industry with Mersen, ERMCO Components and other fuse manufacturers in order to meet your needs.


  • Easy to use with a variety of solutions offered
  • Easy to print and reference fuse coordination curves
  • One-of-a-kind fuse and CSP breaker coordination capability
  • Real-time coordination allows instant feedback and information
  • Experienced transformer design and application engineering expertise available from H-J to support our customers
  • Onsite training and fuse theory courses available on request
  • Thousands of current limiting and expulsion fuses in stock at H-J warehouse
  • Global support from H-J in 20+ offices around the world

Padmount and Substation Style Transformer Protection

This service will allow you to coordinate expulsion and partial-range current limiting fuses to provide a more exact and cost-effective full range protection. Our program will offer a variety of solutions for different applications for you to choose the solution which is most suited for your transformer.

Completely Self Protected (CSP) Transformer Protection

H-J is providing a unique market feature which coordinates CSP breakers together with expulsion fuse protection! We offer this service for those customers and markets where we currently supply CSP breakers. 

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