What should be the IP enclosure rating for panelboards installed in an internal location?

The appropriate response indicates that an IP (Ingress Protection) enclosure rating may not be needed for panelboards installed in internal locations. This determination stems from the fact that equipment located inside a building is typically not exposed to the same environmental hazards as outdoor units, such as dust and moisture.

Panelboards installed in controlled indoor settings where they are protected from direct exposure to elements do not necessitate the same level of protection as those installed outdoors or in environments subject to high levels of dust or water. Therefore, it's common in such internal applications to find that the specific IP rating can be deemed not applicable.

In contexts where panelboards are used in internal locations, the focus often shifts to compliance with other standards and safety regulations rather than strict adherence to specific IP ratings, given that these panels are likely already protected by the building structure itself. This leads to a conclusion where an IP rating may be marked as not applicable since the conditions do not require extra consideration for ingress protection.