Liquid Dielectric Transformers, Power Handling Capacity Not Exceeding 650 KVA

Certain liquid dielectric transformers have been subject to antidumping and countervailing duty orders from specific countries of origin. Importers must check current AD/CVD orders with CBP and the Department of Commerce before entry, as the scope and covered origins can change. A customs broker or trade attorney should review the applicable scope rulings for the specific KVA rating and origin of each shipment.

A liquid dielectric transformer uses an insulating liquid — most commonly mineral oil, but also synthetic esters or silicone fluids — as both the primary electrical insulation medium and the cooling agent surrounding the core and windings. Dry-type transformers, which use air or solid insulation, classify under the non-liquid-dielectric provisions of heading 8504 (subheadings 8504.31–8504.34). The presence or absence of a liquid-filled tank is the key physical distinction CBP examines.