What is the designation for electrical circuits that have high amounts of current through heavier conductors?

The designation for electrical circuits that carry high amounts of current through heavier conductors is best described as high current circuits. This term specifically refers to circuits designed to handle larger amounts of electrical current while minimizing resistance and heat generation. Heavy conductors are essential in these circuits to ensure safety and efficiency, as they are better suited to withstand the increased amperage without overheating or leading to failure.

While "heavy-duty circuits" might seem related, it often refers to the robustness or construction quality rather than the electrical specifications themselves. Other terms such as "low voltage circuits" and "standard circuits" do not accurately represent the capability to handle high current levels and are more focused on unrelated aspects of circuit design. Thus, high current circuits is the most precise and appropriate designation for the context of this question.