NEC General Notes

Single Receptacle

A single receptacle on an individual branch circuit must have an ampacity not less than the rating of the over-current device.

Use of White or Gray Color conductors in a Cable Assembly

The white or gray colored conductors in a Cable Assembly can be re-identified and used as an ungrounded conductor if permanently marked at all locations where the conductor is visible.

200.6(B) An insulated Grounded Conductor or Neutral Size 4 AWG or Larger must be identified with...

1. A continuous white outer finish 2. A continuous gray outer finish 3. Three continuous white stripes along the conductor's entire length other than green insulation. 4. *White or Gray tape or markings at the terminations.

200.6(A) An insulated Grounded Conductor or Neutral Size 6 AWG or Smaller must be identified with...

1. A continuous white outer finish 2. A continuous gray outer finish 3. Three continuous white stripes along the conductor's entire length other than green insulation. 4. A white or gray outer covering with colored tracer threads is acceptable. 5. It is a violation to mark a neutral conductor size 6 AWG or smaller that is not white or gray with white tape.

Calculating Circuits needed for General Lighting and General-Use Receptacles for a dwelling unit....

1. Use Table 220.12 that lists all the different occupancy's with the pre-calculated Volt-Amps needed per Sq-Ft 2. Determine the VA load by multiplying the total Sq-Ft by the pre-calculated VA. Example: 1500 Sq-Ft X 3VA per Sq-Ft = 4500 VA. 3. Determine the Amps by dividing the VA by the voltage (using the PIE Formula). Example 4500 VA (also known as watts) divided by 120V = 38 Amps. 4. If you were using 15 amp breakers, you would need three circuits. If using 20 amp breakers, you would need two circuits.

What size branch-circuit conductors are required for the ungrounded conductors of a 44A continuous load, if the equipment terminals are rated 75° C?

44 A x 1.25 (125% size increase for continuous load) = 55 A Go to table 310.15(B)(16) and find the 75° Column, scroll down to 55 A which does not exist so go to the next highest which is 65 A. Look to the left for the wire size and it is #6 AWG.

210.19(A)(1) Continuous Load (3hrs) Branch circuit conductor sizing

Continuous load conductors must be sized no less than 125% of the continuous loads, plus 100% of the noncontinuous loads, based on the terminal temperature.

Voltage Drop Recommendations

Feeder: 3% Maximum Recommended Voltage Drop Branch Circuit: 3% Maximum Recommended Voltage Drop Combined Feeder & Branch Circuit: 5% Max Voltage Drop.

Dwelling Unit GFCI Requirements...

GFCI Protection is required for all 15 and 20 amp, 125 volt Dwelling Unit receptacles located in the following locations (Per 210.8). 1. Bathrooms 2. Garages and Accessory Buildings such as sheds or work areas. 3. All 15 and 20a receptacle located outdoors of a dwelling unit. 4. All 15-20 amp receptacles installed in Crawl Spaces. 5. All 15-20 amp receptacles installed in unfinished portions of basements. 6. All 15-20 amp receptacles that serve the kitchen counter top surfaces. 7. All 15-20 amp receptacles that within a 6' arc of the outside edge of a sink.

Multiple Receptacle Loading

If connected to a branch circuit that supplies two or more receptacles, the total cord-and-plug-connected load must not exceed 80 percent of the receptacle rating.

Branch Circuit Requirements in a Dwelling Unit (210.11)...

Branch Circuit Requirements in a Dwelling Unit... *Interesting Note: There's no limit to the number of general-use receptacles on a circuit in a dwelling unit. 1. Two or more 20 amp, 120 volt small appliance circuits are required for the 15 amp or 20 amp receptacles in a kitchen, dining room, breakfast nook, pantry, or in a similar dining area. 2. One 20 amp, 120 volt dedicated circuit must be provided a receptacle in the laundry room even if it is not being used. Other receptacles in the laundry room can be on the same circuit but only in the laundry room. 3. One 20 amp, 120 volt dedicated circuit must be provided for the bathroom receptacles and cannot serve any other outlets such as bathroom lighting or other rooms. However, multiple bathrooms can use the same circuit and it the circuit only being used for one bathroom, it is acceptable to use it for lighting in the same bathroom.

Conductor Protection

Branch-Circuit conductors must be protected against overcurrent in accordance with 240.4

Equipment Protection

Branch-Circuit equipment must be protected in accordance with 240.3

AFCI Required Locations in Dwelling Units...

Family Rooms, Dining Rooms, Living Rooms, Parlors, Libraries, Dens, Bedrooms, Sun-rooms, Rec Rooms, Closets, Hallways, Similar Areas *Not Required: Garages, Kitchens, Bathrooms, Porch, Laundry Room.

Commercial or other than Dwelling Unit GFCI Requirements (210.8)...

GFCI Protection requirements for all 15-20 amp, 125 volt receptacles in Commercial or Other than Dwelling Units. 1. All Bathrooms 2. All 15-20 amp Kitchen Receptacles including the ones not above counter tops. *Note: A kitchen is an area with a sink and permanent provisions for food preparations and cooking. A microwave or a hot plate does not qualify as permanent provisions. 3. All 15-20 amp receptacles on Rooftops must be GFCI protected. 4. All 15-20 amp receptacles installed outdoors must be GFCI protected 5. All 15-20 amp receptacles installed within a 6' arc of the outside edge of a sink must be GFCI protected.

Ground-Fault Circuit-Interrupter (GFCI)

The purpose of a GFCI is to interrupt the circuit to protect people against electrocution when it detects a ground fault 6 mA or higher.

Arc-Fault Circuit-Interrupter (AFCI)

The purpose of an AFCI is to interrupt the circuit when it detects an arcing fault to protect against fire hazards.

Voltage Drop Calculation

VD Calculation: EVD=IxR Go to Chapter 9, Table 9 to get the resistance of the conductor. Example: 1.) Source Voltage = 240 v 2.) 10 AWG = 1.20 ohms per 1000' 3.) The Given Load is 24 A 4.) Two ungrounded conductors at 100' long = 200' total 5.) Divide 1.2 ohms by 1000 then multiply it by 200' to get 0.24 ohms. 6.) EVD = I X R: 24 A x 0.24 ohms = 5.76V (Less than 3% VD) 7.) New voltage with voltage drop is 234.2 v

Use of White or Gray Color conductors in Raceway

White or Gray colored conductors cannot be used in a raceway as ungrounded conductors even if taped or marked on both ends or permanently re-identified.