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My house was built in 1973 and has a tiny basement window (single-pane aluminum frame) in a window well. The utility electrical meter is on the same exterior wall, not directly over the basement window.

A few years ago I had some solar panels put on the roof, and they installed all of their meters and inverters right next to the utility electrical meter, so some of their equipment is now directly over the window well.

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I'm considering upgrading the tiny window to an egress window, and I'm wondering if there's any way to do that and still meet code.

It looks like the National Electric Code 110.26(A) says I'm supposed to have 3' of space in front of the meters and inverters, but I can't find anything that talks about requirements for what the ground under that working space looks like.

Is the working space rule satisfied, if any workers have to stand on the grate on the top of my egress window well in order to access the equipment?

I emailed my county planning department and they said "Your proposed grate or cover over the window well shall NOT encroach on these requirements for the any electric devices." That sentence is a little convoluted so I'm not 100% sure, but I think he's saying that I can't do what I want to do?

Betty Crokker
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Working space is:

  • The width of the equipment but at least 30"
  • 78" high
  • 36" deep for these voltages

This only applies to things that need to be read or that have controls. If it's merely a junction box, it simply needs to be accessible without removing parts of the building.

When they initially installed this unit, they added 2 meters, a disconnect switch and a grid-tie inverter. (or possibly more than that?) All that equipment needs working space.

The installation was botched from day 1. From here I would research whether they pulled a permit for this work, and if the installation was approved as-is. If not, I'd call the company back in and tell them to relocate the equipment to a lawful location. Not a word about your building plans, of course.

Mind you, if it were me, and I had one job: make that location legal, I might build a wooden deck there, with a steel grate over the window area to let in light (and with the grate sitting on reliefs in the wooden deck so the grate was electrically isolated). Don't let them do that!

Harper - Reinstate Monica
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That "shield" around the window is itself a Code violation, and also violates your utility's meter placement rules

Your problem is that while the mere presence of a window underneath metering equipment is not a Code violation, the half-round "shield" around the window infringes on the NEC 110.26(A) clearances, which have to be maintained to ground level as per NEC 110.26(A)(3):

(3) Height of Working Space. The work space shall be clear and extend from the grade, floor, or platform to a height of 2.0 m (6½ ft) or the height of the equipment, whichever is greater. Within the height requirements of this section, other equipment that is associated with the electrical installation and is located above or below the electrical equipment shall be permitted to extend not more than 150 mm (6 in.) beyond the front of the electrical equipment.

Furthermore, Xcel's Blue Book requires that the clearspace in front of utility meters be kept clear of all obstructions, as stated in drawing CR-120, note 1. Since from your setup we can see that you have both a customer-owned and a utility-owned production meter over the window, in addition to your main (net) service meter, that utility production meter is required to meet the same clearspace standards as the main service meter, best I can tell.

As a result, you'll need to have the solar company redo this setup to get it out from over the window. If possible, converting to a net metering electric rate would let you get rid of the extra production metering hardware and move the solar disconnect to under the main panel. (You can't get rid of that disconnect altogether, though, since your utility requires a visible blade disconnect for DG/solar production in section 8.3.3 of the metering rules.)

ThreePhaseEel
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