Electrical Association

Ask the Inspector

Answers courtesy of Minnesota Chapter IAEI, minnesotaiaei.org If you have installation questions, submit them to This e-mail address is being protected from spambots. You need JavaScript enabled to view it. and space permitting, we'll have our panel of experts answer them in the next newsletter.

Question:

How much detail is required to comply with the requirement in 408.4 to fill out
the panel directory?

Answer:

Section 408.4 requires every circuit to be legibly identified as to its clear, evident and specific purpose or use. That's pretty easy if the circuit is for a specific purpose or piece of equipment such as the furnace or the refrigerator, but what if it's not an individual branch circuit? What if it serves the receptacles in two rooms, the lighting in three rooms (including one in the basement) and also the light outside the front door?

The index supplied with the panelboard will not be adequate to identify every item that is supplied by each branch circuit, but a few industrious companies have found a painless solution. They have turned the obligation into opportunity and install their company's name inside every panelboard as an integral part of a larger, more detailed circuit directory that can be replaced each time there's a modification.

Inspectors have never failed a job because the panel index contained too much detail.

Question:

Recent changes to the MN Residential Energy Code require passive radon mitigation piping systems to be installed in new single family dwellings. This involves a 4-inch PVC pipe installed from the basement sump basket up through the attic out the roof and the new code specifically requires "an electrical circuit terminated in an approved box" installed in the attic or other anticipated location of the vent pipe fan. What does this mean to the electrical contractor?

Answer:

While it sounds like a rather problematic requirement, a closer look reveals that this can be as simple or complex as you want to make it. Many builders will simply install the active sub-slab depressurization system (meaning the fan is installed) when the home is built, so the lighting and power for the fan is already part of the project. If the builder chooses a passive system (meaning the fan isn't installed) a light switch installed near the attic entrance for a luminaire mounted near the anticipated location of the fan and a receptacle installed within cord length of the piping would certainly meet the energy code requirement. However, simply extending a nearby lighting or power circuit into an accessible area of the attic and terminating it in single-gang device box with a blank cover would also meet the condition.