Types

• Automatic Transfer Switches
  Switches that sense utility power loss and transfer loads to a generator or other alternate source, then back when normal power returns.
• Battery Storage and Resilience Power
  Stationary battery energy storage in buildings, with NFPA 855, UL 9540, and UL 9540A as the governing safety standards and local siting rules.
• Conduit and Raceways
  Metal and nonmetallic conduit, tubing, wireways, and boxes that route and protect electrical conductors through buildings and underground.
• Electric Service to the Site
  How electric power reaches a building from the utility grid, with new-service application, transformer and easement needs, and relocation of lines.
• EV Charging Equipment
  Level 1, Level 2, and DC fast chargers with their circuits and parking infrastructure, used to charge electric vehicles at homes and commercial sites.
• Panelboards
  Wall-mounted cabinets of bus and circuit breakers that protect and distribute branch circuits and feeders to lighting, receptacles, and equipment.
• Rooftop Solar PV
  Photovoltaic modules, racking, inverters, and rapid shutdown equipment mounted on roofs to generate electricity for buildings and the grid.
• Service Entrance and Metering
  The utility connection, service conductors, meters, and service disconnecting means where electrical power enters a building.
• Solar Photovoltaics
  Rooftop and site solar photovoltaic systems, with orientation, tilt, and shading rules of thumb for siting and layout.
• Standby Generators
  Engine-driven diesel, natural gas, or propane generators that supply emergency, legally required, or optional standby power during utility outages.
• Switchboards
  Floor-standing, dead-front assemblies of bus, breakers, and switches that distribute large services to feeders, panelboards, and equipment.
• Transformers
  Dry-type and liquid-filled transformers that step voltage up or down, such as 480 V to 208Y/120 V for lighting and receptacle loads.
• Wiring Devices
  Receptacles, switches, GFCI and AFCI devices, USB outlets, and wall plates that connect people and equipment to branch circuits.

Code reference

Always verify the adopted code edition and local amendments for the project jurisdiction.

Governing editions

NEC 2026 organization

• Article 120: branch-circuit, feeder, and service load calculations, renumbered from Article 220; 120.7 allows a listed power control system setting to size branch circuits, feeders, and services (service entrance and metering, EV charging equipment)
• New Articles 245, 265 to 270, 305, 315, and 495: systems over 1000 V ac / 1500 V dc, replacing deleted Article 235
• Chapter 7, Articles 720 to 760: reorganized limited-energy systems; Article 728 fire-resistive cable moved to Article 772; Article 750 energy management moved to Article 130
• Listing and reconditioned equipment: listing requirements in each article's .2 section and reconditioned equipment in .3

Working space

• NEC 2026, Section 110.26: working space depth by voltage and condition per Table 110.26(A)(1) (3 ft minimum; 3-1/2 ft for Condition 2 and 4 ft for Condition 3 at 151 to 600 V); width at least 30 in. or the equipment width; height 6-1/2 ft or the equipment height; equipment doors open at least 90 degrees; dedicated space from the floor to 6 ft above equipment or the structural ceiling (switchboards, panelboards, transformers, automatic transfer switches). The 2026 edition revises how depth is measured and adds a 24 in. egress path at a 90-degree door opening
• NEC 2026, Section 110.26(C)(2): equipment over 6 ft wide rated 1,200 A or more needs an entrance at least 24 in. wide and 6-1/2 ft high at each end of the working space; 2026 adds feeder disconnect combinations to this rule (switchboards)
• NEC 2026, Section 110.16: arc-flash hazard marking expanded to more equipment (switchboards, panelboards)

Services and protection

• NEC 2026, Section 230.70: service disconnecting means for one- and two-family dwellings readily accessible, outdoors, on or within sight of the dwelling; 230.70(D) requires plaques or directories for other-source disconnects not adjacent to service equipment (service entrance and metering, rooftop solar PV, standby generators)
• NEC 2026, Section 225.41: emergency disconnects for feeders to dwellings (service entrance and metering)
• NEC 2026, Section 210.8: GFCI protection; 210.8(B) expands nondwelling locations and defines special-purpose GFCI Classes C, D, and E; 210.8(F) allows special-purpose GFCIs for outdoor dwelling HVAC outlets (wiring devices)

Standby power

• IBC 2024, Section 2702.1.1: stationary emergency and standby generators listed to UL 2200 (standby generators)
• IBC 2024, Section 2702.1.2: generator fuel lines in high-rise buildings separated by 2-hour protection (1 hour where fully sprinklered) (standby generators)
• IBC 2024, Section 2702.1.3: installation per the IFC, NFPA 70, NFPA 110, and NFPA 111 (standby generators, automatic transfer switches)
• IBC 2024, Section 2702.1.4: emergency power within 10 seconds and standby power within 60 seconds of primary power loss (standby generators, automatic transfer switches)
• IBC 2024, Section 2702.1.5: required power for at least 2 hours without refueling or recharging, unless otherwise stated (standby generators)
• IBC 2024, Section 2702.2: where emergency and standby power is required, including exit signs and egress illumination (90 minutes), emergency responder communication coverage (12 hours), elevators, smoke control, high-rise buildings, and Groups I-2 and I-3 (standby generators)
• IBC 2024, Section 2702.3: critical circuits protected by UL 2196 cable or electrical circuit protective systems rated 1 hour, or 1-hour construction (standby generators, conduit and raceways)
• NEC 2026, Article 702: optional standby systems; new 702.4 provisions for power control systems with inverter-based systems in dwellings; with Section 706.16 deleted, most energy storage systems fall under Article 702 (automatic transfer switches, rooftop solar PV)

EV charging and solar PV

• NEC 2026, Article 625: electric vehicle power transfer systems; new Article 624 covers self-propelled vehicle power transfer (EV charging equipment)
• NEC 2026, Section 690.12: PV rapid shutdown: conductors outside the array boundary limited to 30 V within 30 seconds and to 80 V inside the boundary (rooftop solar PV)
• NEC 2026, Article 705: interconnected power production sources (rooftop solar PV)
• IFC 2024, Section 1205: solar PV roof access; ridge setbacks of 18 in. on each side for arrays covering up to 33 percent of plan roof area and 36 in. above that, with 66 percent thresholds in sprinklered dwellings (rooftop solar PV; secondary source)
• IBC 2024, Section 1505.9: rooftop PV systems tested and listed with racking per UL 2703 (rooftop solar PV)

Accessibility

• 2010 ADA Standards, Section 308: unobstructed forward and side reach 15 in. minimum to 48 in. maximum above the floor (wiring devices, EV charging equipment)

Referenced standards

Sources

• UpCodes: 2024 IBC Chapter 27 electrical (Department of Defense adoption; DoD adds UFC references only), https://up.codes/viewer/department-of-defense/ibc-2024/chapter/27/electrical
• IAEI Magazine: NEC 2026 significant code changes, https://iaeimagazine.org/standards/nec-2026-significant-code-changes/
• Interstates: NEC 2026 changes, key updates to know, https://www.interstates.com/resources/blog/nec-2026-changes-key-updates-to-know
• EC&M: NEC requirements for working clearances, https://www.ecmweb.com/national-electrical-code/code-basics/article/21259374/nec-requirements-for-working-clearances
• Solar Builder: what to know about the 2026 National Electrical Code, https://solarbuildermag.com/featured/what-to-know-about-the-2026-national-electrical-code/
• HeatSpring: the 2026 National Electrical Code is now available online for free, https://blog.heatspring.com/the-2026-national-electrical-code-is-now-available-online-for-free/
• SurgePV: NEC 2026 rapid shutdown, https://www.surgepv.com/blog/nec-2026-rapid-shutdown-solar
• Douglas County, CO: 2024 Appendix Chapter Q solar provisions (Section 1205 text), https://www.douglasco.gov/wp-content/uploads/2026/06/Exhibit-E-2024-Chapter-Q.pdf
• Corada: 2010 ADA Standards Section 308 reach ranges, https://www.corada.com/documents/2010ADAStandards/308