NEC 408: Switchboards, Switchgear, and Panelboards
What This Article Covers
NEC Article 408 covers switchboards, switchgear, and panelboards — the equipment that distributes branch-circuit and feeder power. It specifies layout, working clearance integration with 110.26, and overcurrent protection rules.
Key Requirements
- Panelboards must be marked with their voltage and amperage rating
- Maximum of 42 overcurrent devices in a lighting and appliance branch-circuit panelboard (legacy rule — modern 408.34 simplified)
- Working clearance per 110.26 applies in front of panels
- Bonding and grounding per Article 250 — neutral and ground bonded only at service
- Series-rated combinations must be labeled and listed for that use
Common Field Applications
- Installing a 200A residential service panel
- Adding a sub-panel in a detached garage (four-wire feeder required)
- Checking working clearance for a panel in a closet
Common Mistakes & Inspection Failures
- Installing a panel in a clothes closet (prohibited — 240.24(D))
- Bonding neutral to ground in a sub-panel
- Insufficient working clearance
Related NEC Articles
Have a specific question about NEC 408?
Ask Sparky AI for a plain-English answer with citation.
Ask Sparky AIFrequently Asked Questions
What does NEC 408 cover?
NEC Article 408 covers switchboards, switchgear, and panelboards — the equipment that distributes branch-circuit and feeder power. It specifies layout, working clearance integration with 110.26, and overcurrent protection rules.
What are the key requirements of NEC 408?
Key requirements include: Panelboards must be marked with their voltage and amperage rating; Maximum of 42 overcurrent devices in a lighting and appliance branch-circuit panelboard (legacy rule — modern 408.34 simplified); Working clearance per 110.26 applies in front of panels. See the full requirements list on this page.
What are common mistakes with NEC 408?
Installing a panel in a clothes closet (prohibited — 240.24(D)) Bonding neutral to ground in a sub-panel Insufficient working clearance
Related Resources
Michael B.
IBEW Local 134 Journeyman Electrician · Licensed Electrical Contractor
Michael is a licensed electrical contractor and IBEW Local 134 journeyman with years of field experience. He built Sparky AI after ChatGPT gave him wrong NEC code information on a job — costing him $800 in callbacks. Every answer in Sparky AI is verified against the actual NEC.