Code Quiz: Skin-Effect Heating and Pull Boxes

Fill in the blank with the appropriate answer.

For skin-effect heating, pull boxes installed for pulling the electrically insulated conductor in the ferromagnetic envelope shall be permitted to be buried under the thermal insulation, provided their locations are indicated by ________ markings on the insulation jacket surface and on drawings.

A)  caution

B)  permanent

C)  warning

D) none of the above

Find the