Code library

Code diagrams you can use

One drawing for each section in the library: the clearances, depths, distances and decisions the National Electrical Code sets, as adopted by the 2025 California Electrical Code. Use them on your site, in a class or in a bid package. Just credit CK Electric and Sons.

How to credit a diagram

The diagrams are licensed under Creative Commons Attribution 4.0 (CC BY 4.0). You can copy, share and adapt them, including for commercial work, as long as you give credit, link to the license and say if you changed anything.

Credit line: Diagram: CK Electric and Sons (ckelectricandsons.com), CC BY 4.0

Link the credit to the diagram’s page in this library, for example ckelectricandsons.com/code/300-5.

They are simplified drawings. The official code text and your building department govern.

<a href="https://ckelectricandsons.com/code/300-5"><img src="https://ckelectricandsons.com/img/code/diagrams/nec-300-5-underground-burial-depths.svg" alt="Cross-section of burial depths: 24 in. direct-burial cable, 6 in. rigid conduit, 18 in. PVC, 12 in. home GFCI circuit (120 V, 20 A max), 6 in. landscape lights." width="1200" height="760"></a>
Diagram: <a href="https://ckelectricandsons.com/code/300-5">CK Electric and Sons</a>, <a href="https://creativecommons.org/licenses/by/4.0/">CC BY 4.0</a>

All diagrams, by topic

General rules and working space

NEC 90.4: Who enforces the code on your jobRead the section SVG PNG
NEC 110.3(B): Listing instructions are code requirementsRead the section SVG PNG
NEC 110.12: Professional and skillful work, on the jobRead the section SVG PNG
CEC 110.13: Mounting equipment, and ballasted solarRead the section SVG PNG
NEC 110.14(D): Tighten terminals to the marked torqueRead the section SVG PNG
NEC 110.16: When commercial gear needs arc-flash labelsRead the section SVG PNG
NEC 110.21(B): Warning labels applied in the fieldRead the section SVG PNG
NEC 110.24: Fault current label at a commercial serviceRead the section SVG PNG
NEC 110.26(A): Working space in front of a panelRead the section SVG PNG
NEC 110.26(C)(3): Electrical room doors for 800 A gearRead the section SVG PNG
NEC 110.26(E): Dedicated space above a panelRead the section SVG PNG

Branch circuits, GFCI and AFCI

NEC 200.6: How a neutral wire must be markedRead the section SVG PNG
NEC 200.7: Using a white wire as a hotRead the section SVG PNG
NEC 210.4: Multiwire circuits that share a neutralRead the section SVG PNG
NEC 210.8(A): Where homes need GFCI protectionRead the section SVG PNG
NEC 210.8(B): Where commercial buildings need GFCIRead the section SVG PNG
NEC 210.8(D): GFCI for ranges, dryers and dishwashersRead the section SVG PNG
NEC 210.8(F): GFCI for outdoor outlets and A/C unitsRead the section SVG PNG
NEC 210.11(C): The 20 A circuits every home needsRead the section SVG PNG
NEC 210.12: Which rooms need AFCI protectionRead the section SVG PNG
NEC 210.12(E): When a remodel triggers AFCI protectionRead the section SVG PNG
NEC 210.19: Sizing branch-circuit wire: two checksRead the section SVG PNG
NEC 210.23: What 10, 15 and 20 A circuits may serveRead the section SVG PNG
NEC 210.52(A): The 6-ft rule for wall receptaclesRead the section SVG PNG
NEC 210.52(C): Kitchen countertop and island receptaclesRead the section SVG PNG
NEC 210.52(D): Bathroom receptacle: within 3 ft of the sinkRead the section SVG PNG
NEC 210.52(E): Outdoor receptacles: front, back and deckRead the section SVG PNG
NEC 210.52(G): Garage receptacles: one in every bayRead the section SVG PNG
NEC 210.63: Service receptacle within 25 ft of HVACRead the section SVG PNG
NEC 210.70: Where a home needs a switched lightRead the section SVG PNG

Load calculations

NEC 220.14: How receptacles count in a load calculationRead the section SVG PNG
NEC 220.42: Commercial lighting load: VA per square footRead the section SVG PNG
NEC 220.53: The 75% factor for four or more appliancesRead the section SVG PNG
NEC 220.54: Dryer load: 5,000 VA or the nameplateRead the section SVG PNG
NEC 220.55: How much load an electric range counts forRead the section SVG PNG
NEC 220.82: The optional load calc for one homeRead the section SVG PNG
NEC 220.83: Can an existing home take more load?Read the section SVG PNG
NEC 220.87: Sizing new load from real demand dataRead the section SVG PNG

Services, feeders and outbuildings

NEC 215.2: Sizing a feeder: two checksRead the section SVG PNG
NEC 225.30: One supply to a detached garage or ADURead the section SVG PNG
NEC 225.31(B): Where the garage or ADU disconnect goesRead the section SVG PNG
NEC 230.24: How high overhead service wires must beRead the section SVG PNG
NEC 230.42: Sizing the service-entrance wiresRead the section SVG PNG
NEC 230.67: Whole-house surge protection at the serviceRead the section SVG PNG
NEC 230.70: Where the main service disconnect can goRead the section SVG PNG
NEC 230.71: How many service disconnects you can haveRead the section SVG PNG
NEC 230.79: Smallest service allowed, by building typeRead the section SVG PNG
NEC 230.85: Outdoor emergency disconnect for homesRead the section SVG PNG
NEC 230.95: When a service needs ground-fault protectionRead the section SVG PNG

Overcurrent protection

NEC 240.4(D): Biggest breaker for 14, 12 and 10 AWG wireRead the section SVG PNG
NEC 240.6: Standard breaker and fuse sizesRead the section SVG PNG
NEC 240.21(B): Feeder taps: the 10-foot and 25-foot rulesRead the section SVG PNG
NEC 240.24: Where breakers and fuses can goRead the section SVG PNG
NEC 240.67: Arc energy reduction for big fusesRead the section SVG PNG
NEC 240.87: Arc energy reduction for 1,200 A breakersRead the section SVG PNG

Grounding and bonding

NEC 250.24: Bond neutral and ground only at the serviceRead the section SVG PNG
NEC 250.32: Grounding a detached garage or ADURead the section SVG PNG
NEC 250.50: Every electrode present is bonded togetherRead the section SVG PNG
NEC 250.52: What can serve as a grounding electrodeRead the section SVG PNG
NEC 250.53: Ground rods: 8 ft in the soil, 6 ft apartRead the section SVG PNG
NEC 250.66: Sizing the grounding electrode conductorRead the section SVG PNG
NEC 250.68: The 5 ft rule for water pipe connectionsRead the section SVG PNG
NEC 250.94: The bonding point for cable, phone and fiberRead the section SVG PNG
NEC 250.104: Bonding water pipe, gas pipe and steelRead the section SVG PNG
NEC 250.118: What can serve as the equipment groundRead the section SVG PNG
NEC 250.122: Sizing the equipment ground wireRead the section SVG PNG
NEC 250.130(C): Adding a ground to an old two-prong outletRead the section SVG PNG
NEC 250.142(B): Keep neutral and ground apart past the mainRead the section SVG PNG

Wiring methods, conductors and boxes

NEC 300.4: Protecting cables from nails and screwsRead the section SVG PNG
NEC 300.5: Minimum burial depth for underground wiringRead the section SVG PNG
NEC 300.11: Supporting wiring above a drop ceilingRead the section SVG PNG
NEC 300.15: Where a box or conduit body is requiredRead the section SVG PNG
NEC 310.12: The 83% rule for home service wireRead the section SVG PNG
NEC 310.15: Derating wire for heat and crowdingRead the section SVG PNG
NEC 310.16: Which ampacity column you can useRead the section SVG PNG
NEC 314.16: Box fill: counting what goes in the boxRead the section SVG PNG
NEC 314.20: How far back a box may sit in the wallRead the section SVG PNG
NEC 314.27(C): Ceiling boxes that can hold a fanRead the section SVG PNG
NEC 314.29: Junction boxes must stay reachableRead the section SVG PNG
NEC 334.10: Where NM cable can be usedRead the section SVG PNG
NEC 334.12: Where NM cable is not allowedRead the section SVG PNG
NEC 334.15: Protecting exposed NM cableRead the section SVG PNG
NEC 334.30: Stapling NM cable: 12 in. and 4½ ftRead the section SVG PNG
NEC 334.80: NM cable ampacity and bundled cablesRead the section SVG PNG
NEC 352.44: Expansion fittings on PVC conduitRead the section SVG PNG
CEC 394.12: Insulating around knob-and-tube wiringRead the section SVG PNG

Switches, receptacles, panels and lighting

NEC 404.2(C): A neutral at the light switchRead the section SVG PNG
NEC 404.4: Switches outdoors and near tubsRead the section SVG PNG
NEC 404.8: How high a switch or disconnect can goRead the section SVG PNG
NEC 404.9(B): Grounding a light switchRead the section SVG PNG
NEC 406.4(D): Replacing a receptacle: what is allowedRead the section SVG PNG
NEC 406.9: Outdoor covers and the tub and shower zoneRead the section SVG PNG
NEC 406.12: Where receptacles must be tamper-resistantRead the section SVG PNG
CEC 408.2: Reserved breaker spaces in new homesRead the section SVG PNG
NEC 408.4: Labeling every circuit in a panelRead the section SVG PNG
NEC 408.36: Protecting a panel and back-fed breakersRead the section SVG PNG
NEC 408.41: One neutral per terminalRead the section SVG PNG
NEC 410.10(D): Lights over a tub or showerRead the section SVG PNG
NEC 410.16: Light fixtures in a clothes closetRead the section SVG PNG
NEC 410.71: A disconnect for tube-lamp fixturesRead the section SVG PNG
NEC 410.116: Recessed lights and attic insulationRead the section SVG PNG

Appliances, HVAC, motors and generators

NEC 409.110: What an industrial control panel must showRead the section SVG PNG
CEC 422.3: Electric-ready gas water heater, range, dryerRead the section SVG PNG
NEC 422.5: Which appliances need GFCI protectionRead the section SVG PNG
NEC 422.16: Plug-in dishwasher, disposal and range hoodRead the section SVG PNG
NEC 422.31: Shutoff for a hardwired applianceRead the section SVG PNG
NEC 430.32: Sizing motor overloads from the nameplateRead the section SVG PNG
NEC 430.102: Where the motor disconnect goesRead the section SVG PNG
CEC 440.3: Heat-pump-ready circuit at a gas furnaceRead the section SVG PNG
NEC 440.14: Where the AC disconnect can goRead the section SVG PNG
NEC 445.18: Generator disconnect and emergency shutdownRead the section SVG PNG

Special locations

NEC 547.44: Equipotential plane at a livestock watererRead the section SVG PNG
NEC 555.35: Ground-fault protection on a dockRead the section SVG PNG
NEC 590.6: GFCI for job-site temporary powerRead the section SVG PNG

EV charging, pools and solar

CEC 625.1.1: EV-ready garages and parking in new buildingsRead the section SVG PNG
NEC 625.40: When an EV charger needs its own circuitRead the section SVG PNG
NEC 625.42: Sizing EV service and feeders to a managed loadRead the section SVG PNG
NEC 625.43: Lockable disconnect for large EV chargersRead the section SVG PNG
CEC 625.52: When indoor EV charging needs ventilationRead the section SVG PNG
NEC 625.54: GFCI for every EV charging receptacleRead the section SVG PNG
NEC 680.21: GFCI for pool pump motorsRead the section SVG PNG
NEC 680.22: Receptacles and lights around a poolRead the section SVG PNG
NEC 680.26: Equipotential bonding around a poolRead the section SVG PNG
NEC 680.44: GFCI for spas and hot tubsRead the section SVG PNG
NEC 680.71: Jetted tub circuit and nearby GFCIRead the section SVG PNG
NEC 690.8: Sizing solar PV circuit current and wireRead the section SVG PNG
NEC 690.12: Solar rapid shutdown on a houseRead the section SVG PNG
NEC 690.13: The PV system disconnectRead the section SVG PNG

Backup power, solar interconnection and batteries

NEC 700.12: Emergency power within 10 secondsRead the section SVG PNG
NEC 701.12: Legally required standby: 60 seconds maxRead the section SVG PNG
NEC 702.4: How big a whole-home generator must beRead the section SVG PNG
NEC 702.5: Generator hookups need listed transfer gearRead the section SVG PNG
NEC 705.11: Supply-side (line-side tap) solar connectionRead the section SVG PNG
NEC 705.12: The 120% rule for solar and battery breakersRead the section SVG PNG
NEC 705.13: Power control (EMS) for solar and batteriesRead the section SVG PNG
NEC 705.20: The disconnect for solar and other sourcesRead the section SVG PNG
CEC 706.10: Battery-ready wiring for new California homesRead the section SVG PNG
NEC 706.15: Home battery disconnects and shutdown switchRead the section SVG PNG
NEC 710.15: Off-grid systems: sizing and 120 V panelsRead the section SVG PNG

Low-voltage and fire alarm

NEC 722.135: Low-voltage cable: plenum, riser, substitutesRead the section SVG PNG
CEC 760.1.1: Fire alarm wiring and NFPA 72 in CaliforniaRead the section SVG PNG

Tables

NEC Chapter 9, Table 1: Conduit fill: 53%, 31%, 40% and 60%Read the section SVG PNG
NEC Chapter 9, Table 8: Wire size, circular mils and resistanceRead the section SVG PNG

San Clemente · South OC to North County San Diego

Send a photo. Get a real answer.

Text is fastest, and a photo quote is free. Call if it is urgent, if you smell something burning, or if a breaker will not reset.

Call Shane· (949) 702-0385 Text Shane a photo

CSLB #354550 · C-10 Electrical · Licensed since 1978 · $25,000 contractor's bond