NEC Architecture flashcards
NEC Architecture · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Working space depth
- The minimum clear distance in front of electrical equipment, typically 3 ft for 0–150 V to ground, 3.5 ft for 151–600 V, and 4 ft for 601–1000 V, per Table 110.26(A)(1).
- Listed equipment
- Equipment that is included in a list published by a nationally recognized testing laboratory (NRTL) and found to meet designated standards.
- Receptacle spacing rule
- In dwelling units, receptacle outlets must be installed so that no point along the floor line in any wall space is more than 6 ft from a receptacle.
- GFCI protection locations
- Required for 125-V, 15- or 20-A receptacles in bathrooms, garages, outdoors, kitchens, laundry areas, and within 6 ft of sinks in dwelling units.
- AFCI requirement
- Arc-fault circuit-interrupter protection is required for 120-V, 15- or 20-A branch circuits supplying dwelling unit bedrooms, living rooms, and similar areas.
- NM cable ampacity
- Ampacity must be limited to the 60°C column of Table 310.16, and the 90°C rating may be used only for derating purposes.
- Conductor adjustment factors
- For more than three current-carrying conductors in a raceway, apply factors: 4–6 conductors = 80%, 7–9 = 70%, 10–20 = 50%.
- EMT support spacing
- EMT must be securely fastened within 3 ft of each box and supported at intervals not exceeding 10 ft.
- Motor branch-circuit conductors
- Conductors supplying a single motor must have an ampacity not less than 125% of the motor full-load current rating.
- Transformer overcurrent protection
- Primary overcurrent protection for transformers must be not more than 125% of the primary current, unless otherwise permitted by Table 450.3(B).
- Commercial garage classification
- Areas within 18 in. of the floor are Class I, Division 2; areas above 18 in. are unclassified unless otherwise specified.
- Health care redundant grounding
- Patient care areas require an insulated copper equipment grounding conductor and a metal raceway or cable armor for redundant grounding.
- Pool receptacle location
- Receptacles must be located not less than 6 ft from the inside wall of the pool and be GFCI-protected.
- Emergency system battery capacity
- Battery capacity must be sufficient for 1.5 hours of operation at full load for emergency systems.
- Optional standby transfer switch
- A transfer switch must be provided to prevent inadvertent interconnection between the optional standby source and the normal supply.
- Busbar 120% rule
- The sum of the ampere ratings of all overcurrent devices on a panelboard, both load and supply, excluding the main, must not exceed 120% of the busbar rating.
- Communications cable support
- Communications cables must be supported at intervals not exceeding 4 ft and within 12 in. of boxes.
- Coaxial cable bonding
- Coaxial cable shields must be bonded to the grounding electrode system at the point of entry using a listed grounding conductor.
- Table 250.66 sizing
- Grounding electrode conductor size is based on the service-entrance conductor size; for 2 AWG or smaller, use 8 AWG copper.
- Table 220.55 range demand
- For one household electric range up to 12 kW, the demand load is 8 kW per Table 220.55.
- Plan review working space
- Verify that the plans show working space around electrical equipment meeting the depth, width, and height requirements of 110.26.
- Available fault current
- Equipment must have an interrupting rating or short-circuit current rating not less than the available fault current at the terminals.
- Service-entrance conductor sizing
- Service-entrance conductors must have ampacity not less than the load and not less than the rating of the service disconnect.
- Small conductor protection
- Overcurrent protection limits: 14 AWG copper-15 A; 12 AWG-20 A; 10 AWG-30 A, unless otherwise permitted by the Code.
- Grounding electrode types
- Include metal water pipe (10 ft or more in contact with earth), metal frame of building, concrete-encased electrode, ground ring, rod/pipe electrode, and plate electrode.
- PVC conduit support
- PVC conduit must be supported at intervals not exceeding 3 ft, and within 3 ft of boxes and fittings.
- Switch height
- Switches and circuit breakers must be installed so that the center of the grip of the operating handle is not more than 6 ft 7 in. above the floor.
- Fire pump disconnecting means
- Must be installed ahead of other building loads and be marked 'Fire Pump' to ensure continuous power.
- PV system maximum voltage
- The maximum PV system voltage is the sum of the rated open-circuit voltages of the modules corrected for the lowest expected ambient temperature.
- Assembly occupancies wiring
- Fixed wiring must be in metal raceways or metal-clad cables, or listed plenum cables where required.
- Elevator traveling cable support
- Traveling cables must be supported at intervals not exceeding 6 ft and be listed for the purpose.
- Critical operations power systems
- COPS must be designed so that a single fault does not cause loss of power to the critical load.