Based on the 2020 NEC.
Many of the Code concerns I write about in these “Practically Speaking” articles come from questions asked by my students, seminar attendees, or electricians simply looking for guidance. When an electrician asked me if show window receptacle outlets are required to be installed on the inside or outside of the show window, I paused for a moment before I gave my answer. Instinctively, I wanted to say they are required to be installed on the inside of the occupancy rather than the outside. But before I could give my answer, that electrician fired off another question, asking if they are required on both the inside and the outside. Great question! When I asked him why he thought receptacle outlets would be needed on the outside of the show window, he smartly said, “For the same reason they’re needed on the inside — somebody may want to plug something in.” Great answer! This seemed like a great topic for this column.
Looking at the displays set up on the outside of the stores in the photo, I think this particular electrician made some valid points. I have seen many stores with twinkle lights or strings of lights used to enhance and light up exterior displays. The Art. 100 definition of “show window” is very broad and includes any window used or designed to be used for displaying goods or advertising material. Would this include goods or materials displayed around the outside of the window too? Why not?
The wording in Sec. 210.62 does not specify whether the 125V, single-phase 15A or 20A receptacle outlet is required to be installed either on the inside or the outside of the window or perhaps even both the inside and the outside. It requires the receptacle outlet to be installed within 18 in. of the top of a show window for every 12 linear feet of show window width, but never specifies inside, outside, or both. I believe the intent is to require receptacles on the inside of the occupancy, but I suppose the literal wording could use some clarification on this matter. As always, I recommend contacting your AHJ if you need guidance trying to decipher these sometimes seemingly unclear Code rules.
