Laundry GFCI receptacles
Q: Are all 15- and 20-ampere, 125V receptacles installed within six feet of a laundry or utility sink in a dwelling occupancy required to be protected by a ground fault circuit interrupter even where the receptacle is not readily accessible such as behind a clothes washer or a dryer?
A: Yes, the change in 210.8(A)(7) requires GFCI protection for all 15- and 20-ampere, 125V receptacles installed within six feet of the outside edge of the sink. The requirement for GFCI protection of receptacles within six feet of laundry and utility sinks was added to the 2005 edition of the NEC and applies to all receptacles that are within six feet regardless of whether receptacles are readily accessible.
Receptacles behind clothes washers, clothes dryers and other appliances are not exempt from the GFCI requirement. Item 7 in 210.8(A) applies to all receptacles that are within six feet and reads like this: “Laundry, utility and wet-bar sinks—where the receptacles are installed within 1.8m (6 ft.) of the outside edge of the sink.” There is no exception to this rule. All 15- and 20-ampere, 125V receptacles within six feet of the sink must be protected by a GFCI.
Fire pump power source
Q: What are some of the things an electrical inspector must consider in determining if a utility service for a fire pump is reliable?
A: The first thing is to determine if you are the authority having jurisdiction (AHJ) for the installation of the fire pump. Rules in Article 695-Fire Pumps in the National Electrical Code do not require the installation of this equipment.
I suspect that some other agency such as the building official, fire marshal or fire department superintendent has authority to require the installation of a fire pump. Whichever agency adopts NFPA 20-Standard for the Installation of Stationary Pumps for Fire Protection is the one responsible for making decisions about the reliability of the power supply, the acceptance of a limited service motor controller, acceptability of the water source and other things.
Here is some information on the reliability of an electric power source taken from Annex A of NFPA-20: “A 9.2.4 A reliable power source possesses the following characteristics: (1) Infrequent power disruptions from environmental or man-made conditions; (2) A separate service connection or connection to the supply side of the service disconnect; (3) service and feeder conductors either buried under 50 mm (2 inches) of concrete or encased in 50 mm (2 inches) of concrete or brick within a building.”
Reliability is hard to define and has different interpretations among various enforcement authorities; therefore, an electrical inspector should not determine the reliability of an electrical power supply to an electric motor-driven fire pump unless he is sure that he is the AHJ.
Conductor color requirements
Q: Does the NEC require different colors on conductors that are used on 120/240V, single-phase circuits and 480Y/277 branch circuits where both voltages are present in the same building? If the answer is yes, are colors other than white and black available in two-wire AC and MC cables?
A: A change in the 2005 edition of the National Electrical Code makes identification of conductors mandatory. Here is the way Part (C) of 210.5 reads: “(C) Ungrounded conductors. Where the premises wiring system has branch circuits supplied from more than one nominal voltage system, each ungrounded conductor of a branch circuit, where accessible, shall be identified by system. The means of identification shall be permitted to be by separate color coding, marking tape, tagging, or other approved means and shall be permanently posted at each branch-circuit panelboard or similar branch-circuit distribution equipment.” This same requirement applies to feeders and is located in 215.12(C).
Manufacturers of Types AC and MC cables produce two-wire cables with various color combinations. Most, if not all, electrical supply houses can order color combinations that satisfy your needs if not in stock. Delivery should not take more than a few days.
Receptacles installed outdoors
Q: If GFCI-protected receptacles are installed outdoors in public places and new vending machines are plugged into these receptacles, will nuisance tripping of these GFCIs occur because there will be two GFCI devices in series with each other?
A: This question points out two changes in the 2005 edition of the NEC. The first appears in 210.8(B)(4) and requires all 15- and 20-ampere, 125V receptacles installed outdoors that are accessible to the public to be GFCI protected. A definition of a public space is “… any space that is for use by or is accessible to the public.”
An addition in Article 422-Appliances requires GFCI protection on all vending machines manufactured or remanufactured after Jan. 1, 2005.
GFCI protection must be provided by the electrical contractor for 15- and 20-ampere outdoor receptacles and also by the manufacturer of vending machines. In some situations, the result will be two GFCIs in series with each other, but this will not cause nuisance tripping of either GFCI device.
Connecting kitchen hood fans
Q: I am an electrician doing house wiring. I have been asked to install a 15-ampere, 120V dedicated branch circuit with a receptacle in the kitchen above the range to supply a cord-and-plug connected hood exhaust fan. This circuit is also intended to supply a microwave oven. Is a 15-ampere branch circuit with a duplex receptacle permitted in this area by the National Electrical Code?
A: You are permitted to install a 15-ampere receptacle protected by a 15-ampere overcurrent device provided that it is more than 20 inches above the counter top. All receptacles above a kitchen counter top are required to be supplied by a 20-ampere branch circuit and 210.52(B)(5) limits the height to a maximum of 20 inches; therefore, a receptacle located more than 20 inches above the counter top is not classified as a counter top receptacle.
Range hoods are permitted to be cord-and-plug connected provided the installation meets all of the requirements in 422.16(B)(4). They are (1) installation requirements as outlined by the manufacturer are followed, (2) the flexible cord is terminated in a grounding-type attachment plug if the hood is not double insulated, (3) the length of the cord is not less than 18 inches and not over 3 feet, (4) the receptacle is located to avoid physical damage to the cord, (5) the receptacle is accessible, and (6) the receptacle is supplied by an individual branch circuit.
An individual branch circuit is defined in Article 100 as: “A branch circuit the supplies only one utilization equipment.” Therefore, the branch circuit has to terminate in a single 15-ampere receptacle and a different branch circuit is needed for the microwave oven, which could be a counter top receptacle circuit.
Q: Where reinforcing rods in a concrete footing are used as a grounding electrode, is the grounding-electrode conductor connection required to be made in the concrete or is it permissible to bend the reinforcing rod up and make the connection out of the concrete? May this grounding-electrode conductor be connected to the water pipe or does it have to be connected to the neutral bus in the service disconnect?
A:The 4 AWG copper or larger grounding-electrode conductor from the reinforcing steel may be connected to the water pipe if it is buried, metal and 10 feet or more in length.
This is permitted by 250.64(F), which allows the grounding-electrode conductor to be run to any convenient grounding electrode in the grounding-electrode system. The grounding-electrode conductor from the reinforcing steel must be connected to the water pipe within five feet of where it enters the building.
The grounding-electrode conductor connection to the rebar can be made in the concrete or out of the concrete. Although the connection of the grounding-electrode conductor is required to be accessible by 250.68(A), an exception exempts encased or buried connections from this requirement.
Temporary power GFCI protection
Q: Where providing temporary electric power for a construction site, the general contractor is requesting two 20-ampere, 125V receptacles and one 50-ampere, 240V receptacle. Is GFCI protection required for the 50-ampere receptacle?
A: GFCI protection is required for the 20-ampere receptacles to comply with 590.6(A). If the construction power is for an addition to an industrial establishment and qualified personnel will service and maintain the equipment, an assured equipment-grounding conductor program may be substituted for GFCI protection for receptacles that supply equipment that would create a great hazard if power was interrupted.
The 50-ampere, 240V receptacle must be protected by a GFCI or must be inspected and maintained under the “assured equipment-grounding conductor program” outlined in 590.6(B)(2). All of the tests mentioned in 590.6(B)(2) must be conducted every three months or less, recorded and made available to the AHJ. EC
FLACH, a regular contributing Code editor, is a former chief electrical inspector for New Orleans. He can be reached at 504.734.1720.