Technical FAQs

Ask a Question

How is the integrated rating calculated for HVL switches with boric acid fuses. How is the MVA calculated for the switch only?

Integrated rating for HVL switches with boric acid fuses:

The integrated rating is limited by the switch to less than the full interrupting capability of the fuse.

Three Phase MVA = system nominal voltage, kV X symmetrical amperes, kA X 1.732

For example on the 38kV HVL switch - look for the lowest rating of the switch. In this case it is the fault close rating of 20kA Asym.

20kA Asym Amps = 12.5kA Sym Amps

The nominal voltage is 34.5kV for this example.

Therefore the Three Phase MVA is 34.5kV X 12.5kA X 1.732 =
747 MVA

Integrated ratings can be found in Tables in the Pricing Guides and Catalog Sections for the Product.


CTA-ID : 2011148
Was this helpful?
What can we do to improve the information ?